CT Analyzer User Manual - User Equip: New & Used Test...

CT AnalyzerUser Manual

QUICK AND EASY TESTING OF PROTECTION AND MEASUREMENT

CURRENT TRANSFORMERSACCORDING TO COMMON STANDARDS

2

CT Analyzer

Article Number VESD0605 - Manual Version: CTAnalyzer.AE.6

With regard to the functionality of the software, this manual refers to version 3.00 for the CT Analyzer firmware,

version 3.00 for the CT Analyzer PC Toolset software andversion 1.4x for the CPC Explorer software.

© OMICRON electronics 2008

This User Manual is a publication of OMICRON electronics GmbH.

All rights including translation reserved. Reproduction of any kind, e.g., photocopying, microfilming orstorage in electronic data processing systems, requires the explicit consent of OMICRON electronics.Reprinting, wholly or in part, is not permitted.

This User Manual represents the technical status at the time of printing. The product information,specifications, and all technical data contained within this user manual are not contractually binding.OMICRON electronics reserves the right to make changes at any time to the technology and/orconfiguration without announcement. OMICRON electronics is not to be held liable for statements anddeclarations given in this User Manual. The user is responsible for every application described in thisUser Manual and its results. OMICRON electronics explicitly exonerates itself from all liability formistakes in this manual.

OMICRON electronics translates this manual from its source language English into a number of otherlanguages. Any translation of this manual is done for local requirements, and in the event of a disputebetween the English and any non-English versions, the English version of this manual shall govern.

Contents

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Contents

Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Safety Instructions for CT Analyzer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10General Rules for Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Orderly Practices and Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10Operator Qualifications and Primary Responsibilities . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Safe Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12Changing Fuses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136 Safety Rules for Your Own Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

1 Designated Use and Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .151.1 Designated Use . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 151.2 Features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

2 Hardware . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .192.1 Functional Components of the CT Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

2.1.1 Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 192.1.2 Mains Connection Unit and Grounding . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202.1.3 Compact Flash Card Slot . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 202.1.4 Inputs and Outputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212.1.5 I/0 Key with Status LEDs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 212.1.6 Display. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2.2 Block Diagram (Simplified) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

3 Connecting the CT Analyzer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .253.1 Basic Wiring for a Burden Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 253.2 Basic Wiring for a CT Test. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 263.3 4 Wire Measurement vs. 2 Wire Measurement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4 Running an Automatic Parameter Search and CT Test (Guesser Function) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .314.1 Connecting the CT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314.2 Preparing the Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314.3 Running the Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

CT Analyzer

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5 User Interface and Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .355.1 Introduction and Basic Operating Procedures. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

5.1.1 Overview of Test Cards. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 355.1.2 Working with the User Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

5.2 CT Analyzer Help System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 385.3 Main Menu. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40

5.3.1 New CT-Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 405.3.2 File Handling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 445.3.3 Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 485.3.4 Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

5.4 CT-Object Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 565.4.1 Available Soft Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 565.4.2 Information Fields to be Filled by the User . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 575.4.3 Parameters and Settings Used or Determined by the Test Process. . . . . . . . . . 58

5.5 Burden Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725.5.1 Test Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 725.5.2 Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 735.5.3 Connecting the Burden and Running the Test . . . . . . . . . . . . . . . . . . . . . . . . . . 73

5.6 Resistance Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 755.6.1 Test Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 755.6.2 Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76

5.7 Excitation Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 775.7.1 Available Soft Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 785.7.2 Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 785.7.3 Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 785.7.4 Excitation Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 855.7.5 K-Value Error Graph . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 88

5.8 Ratio Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 905.8.1 Available Soft Keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 905.8.2 Settings . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 915.8.3 Test Results . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 915.8.4 Ratio Table and Phase Table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

5.9 Assessment Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 965.9.1 Assessed Parameters . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 975.9.2 Conditions for a Positive Assessment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100

5.10 Comment Card . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107

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6 CT Analyzer PC Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1096.1 System Requirements . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1096.2 Installation of the CT Analyzer PC Toolset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

6.2.1 Installing the CT Analyzer PC Toolset. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1106.2.2 Update for CPC Explorer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 110

6.3 The CTA Start Page . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1116.3.1 Version Number and "Updates available!" Link. . . . . . . . . . . . . . . . . . . . . . . . . 1126.3.2 CT Analyzer Tools. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1126.3.3 Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1136.3.4 Support . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 114

6.4 CTA QuickTest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1166.4.1 Starting CTA QuickTest. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1166.4.2 Using CTA QuickTest . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 116

6.5 CTA Remote Excel File Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1236.5.1 Starting the CTA Remote Excel File Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . 1236.5.2 Data Sheet . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1256.5.3 Using User-Defined Code in the CTA Remote Excel File Loader . . . . . . . . . . . 129

6.6 CT Analyzer Firmware Update Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1316.6.1 General Information About Updating the Firmware and the

User Interface Language Files . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1316.6.2 Starting the CT Analyzer Firmware Update Tool. . . . . . . . . . . . . . . . . . . . . . . . 1326.6.3 Using the CT Analyzer Firmware Update Tool . . . . . . . . . . . . . . . . . . . . . . . . . 133

6.7 CTA Remote Control Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1366.7.1 Sample Software for CTA Remote Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 136

6.8 CTA to NetSim Export Tool . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1376.9 CPC Explorer for CT Analyzer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 138

6.9.1 General . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1386.9.2 Installation of the CPC Explorer Software . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1386.9.3 Using the CPC Explorer with the CT Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . 139

CT Analyzer

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7 Application Examples . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1437.1 Measurement at a Freely Accessible CT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1437.2 Measurement at a Delta Winding Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145

7.2.1 Ratio Measurement at a Delta Winding Transformer with Delta Compensation 1467.2.2 Ratio Measurement at a Delta Winding Transformer without

Delta Compensation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1467.3 Measurement at a Wye Winding Transformer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1477.4 Measurement at a Bushing-Type CT. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1487.5 Measurement at a GIS (SF6) Switch Gear . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1507.6 Measurement on a Bar-Type Current Transformer . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1527.7 Measurement on Tapped CTs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1547.8 Measurement on a Gapped Core . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1557.9 Excitation Curve Measurement for an Unwound Iron Core . . . . . . . . . . . . . . . . . . . . . . 1567.10 Measurement on Multicore CTs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1577.11 Burden Test . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1577.12 Noise Reduction Techniques. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 158

8 Calibrating the CT Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .161

9 Error and Warning Messages . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .163

10 Formulas and Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17510.1 Calculation of Ratio Error (Current Ratio) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17510.2 Turns Ratio Error . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17710.3 Calculation of RCF for IEEE C57.13 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17810.4 Calculation of e.m.f. rms Voltage (Uc) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17810.5 Calculation of Instrument Security Factor (FS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

10.5.1 Calculation of Instrument Security Factor (FS) according to the Direct Measurement Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 179

10.5.2 Calculation of Instrument Security Factor (FSi) according to the Indirect Measurement Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 181

10.5.3 Example for Verification of FSi . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18210.6 Calculation of Accuracy Limiting Factor (ALF) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

10.6.1 Calculation of Accuracy Limiting Factor (ALF) according to the Direct Measurement Method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 184

10.6.2 Calculation of Accuracy Limiting Factor (ALFi) according to the Indirect Measurement Method. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 186

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10.7 Calculation of Peak Instantaneous Error (ε^) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18710.8 Calculation of Rated Symmetrical Short Circuit Current Factor (Kssc) . . . . . . . . . . . . . 18710.9 Calculation of Dimensioning Factor (Kx) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 18810.10 Calculation of Secondary Loop Time Constant (Ts) . . . . . . . . . . . . . . . . . . . . . . . . . . . 18810.11 Calculation of Rated Secondary Terminal Voltage (VB) acc. to IEEE C57.13. . . . . . . . 18910.12 Remanence Factor (Kr) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19010.13 Saturated Inductance (LS) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19110.14 Non-saturated Inductance (Lm) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19210.15 Knee Point . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19210.16 Class Definition . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 193

10.16.1Class Definition According to (ANSI) IEEE C57-13.1-1981 Protection . . . . . . . 19310.16.2Class Definition According to IEC 60044-6 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19310.16.3Class Definition According to IEC 60044-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . 194

10.17 Determination of Transient Dimensioning Factor (Ktd) . . . . . . . . . . . . . . . . . . . . . . . . . 19610.17.1Calculation for Class TPZ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19610.17.2Calculation for Class TPX, TPY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196

10.18 Parameter Search Function (Guesser Function). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19810.19 Guesser Algorithm for Burden . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20410.20 Burden Entry Logic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205

11 Parameter Definition Syntax for the Different Standards . . . . . . . . . . . . .20711.1 How to Read the Parameter Definition Syntax Charts . . . . . . . . . . . . . . . . . . . . . . . . . 20711.2 Parameter Definition Syntax for IEC 60044-1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20811.3 Parameter Definition Syntax for IEC 60044-6 Classes TPS and TPZ. . . . . . . . . . . . . . 20911.4 Parameter Definition Syntax for IEC 60044-6 Classes TPX and TPY. . . . . . . . . . . . . . 21011.5 Parameter Definition Syntax for IEEE C57.13. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 211

12 Care and Cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .213

CT Analyzer

8

13 Technical Data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21513.1 Mains Power Supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21513.2 Generator Output. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21513.3 Measurement Inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21613.4 Winding Resistance Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21613.5 Ratio and Phase Accuracy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21713.6 Insulation Coordination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21913.7 Compact Flash Card Interface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22013.8 Remote Control Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22013.9 Environmental Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22113.10 Electromagnetic Compatibility (EMC) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22113.11 Safety Standards . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22213.12 Weight and Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222

14 Scope of Delivery and Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22314.1 CT Analyzer CT1 incl. Accessories . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22314.2 CT Analyzer Standard Package . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22314.3 Accessories Set for CT Analyzer. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22414.4 Additional Accessories for CT Analyzer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225

Contact Information / Technical Support . . . . . . . . . . . . . . . . . . . . . . . . . .229

Index . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .231

Preface

9

PrefaceThe purpose of this user manual is to familiarize users with the CT Analyzer and its application fields. It contains helpful instructions on how to use the CT Analyzer safely, properly, and efficiently.

Following these instructions will help you to prevent danger, repair costs and possible down time due to incorrect operation. Furthermore it ensures the reliability and life-cycle of your CT Analyzer.

The CT Analyzer must be used in observance of all existing safety requirements from national standards for accident prevention and environmental protection.

Reading the CT Analyzer manual alone does not release the user from the duty of complying with all national and international safety regulations relevant for working with the CT Analyzer.

The user manual always has to be available at the site where the CT Analyzer is used. It should be read and used by all people working with the CT Analyzer.

In addition to the user manual and the applicable regulations for accident prevention in the country and at the site of operation, the accepted technical procedures for safe and competent work should be heeded.

Glossary of SymbolsIn this manual, different symbols are used to highlight text of special safety and/or operational relevance. These symbols are listed below.

NoteIndicates notes with special meaning, i.e., additional important information.

CautionIndicates sections with special safety-relevant meaning.

Electrical Danger - CautionEmphasizes actions or instructions that hold potential risk to health and life. To be carried out by authorized personnel with extreme caution and full awareness of the safety regulations only.

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10

Safety Instructions for CT AnalyzerBefore operating the CT Analyzer, please carefully read the following safety instructions. It is not recommended to use (or even switch on) the CT Analyzer without understanding the information in this manual. If some points of the safety instructions are unclear, please contact OMICRON electronics.

The operator is responsible for the observance of all applicable safety requirements during the entire test. When performing tests in high-voltage areas, pay attention to the national and international standards for safe operation of high-voltage test equipment (EN 50191, IEEE 510, and others).

General Rules for Use• The CT Analyzer should only be used when in a technically sound condition.

• Its use should be in accordance with the safety regulations for the specific job site and application.

• Always be aware of the dangers of the high voltages and currents associated with this equipment. Pay attention to the information provided in the operations manual.

• The CT Analyzer is intended exclusively for the application areas specified in section 1.1 on page 15. Any other use is deemed not to be according to the regulations. The manufacturer/distributor is not liable for damage resulting from improper usage. The user alone assumes all responsibility and risk.

• Following the instructions provided in this user manual is also considered part of being in accordance with the regulations.

• Do not open the CT Analyzer. Opening the CT Analyzer invalidates all warranty claims.

Orderly Practices and Procedures• The user manual, or alternatively the "electronic manual" in PDF form, should

always be available on the site where the CT Analyzer is being used.

• Personnel assigned to use the CT Analyzer should carefully read the user manual - in particular this section on safety instructions - before beginning to work with it. This also applies to personnel who only occasionally work with the CT Analyzer.

• Do not undertake any modifications, extensions, or adaptations to the CT Analyzer.

• Use the CT Analyzer in conjunction with original accessories only.

Safety Instructions for CT Analyzer

11

Operator Qualifications and Primary Responsibilities• Testing with the CT Analyzer should only be carried out by authorized and

qualified personnel. Clearly establish the responsibilities!

• Personnel receiving training, instruction, direction, or education on the CT Analyzer should remain under the constant supervision of an experienced operator while working with the equipment.

Safe OperationIf working in other than laboratory environment only use the CT Analyzer with a solid connection to ground of at least 6mm2. Use a ground point as close as possible to the test object.

• When disconnecting cables, always start at the device feeding the power.

• Never connect or disconnect a test object while the outputs are active. Lethal voltages can occur due to the high energy stored in external inductors.

• During the test always connect one terminal of the transformer’s primary side to protective earth.

• Do not insert objects (e.g. screwdrivers, etc.) into the ventilation slots or any input/output sockets.

• Before putting the CT Analyzer into operation, check the test set for visible damages.

• Do not operate the CT Analyzer under wet or moist conditions (condensation).

• Do not operate the CT Analyzer when explosive gas or vapors are present.

• When taking the CT Analyzer into operation, make sure that the air slots, the power switch and the power supply plug at the test set remain unobstructed.

• Voltages of up to 400V can occur inside the CT Analyzer! Therefore, only qualified personnel at the factory is permitted to open the CT Analyzer.

• If the CT Analyzer seems to be functioning improperly, please call the OMICRON Hotline (refer to chapter "Contact Information / Technical Support" on page 45).

• For protection against parasitic currents or voltages, always connect the equipotential connector on the CT Analyzer’s side panel (see section 2.1.2 on page 20) to protective ground (PE). Only use the cable set listed in section 14.2 on page 223.

CT Analyzer

12

• Make sure that the terminals of the test object to be connected to the CT Analyzer do not carry any voltage potential. During a test, the CT Analyzer is the only permitted power source for the test object.

• Never connect or disconnect a test object while the outputs are active.

• When measuring the ratio of transformers make sure that the test voltage is connected to the corresponding secondary winding, and the primary winding is connected to the according measurement input. Accidentally mixing up the windings can cause life-threatening voltages within the transformer and/or destroy the connected CT or the CT Analyzer!

• Only use wires with 4mm safety "banana" connectors and plastic housing for connection to the front panel input/output sockets.

• Do not stand right next to or directly underneath a connection point because the clamps may fall off and touch you.

• Flashing lights on the front panel indicate that the CT Analyzer output is active and hazardous voltages can be present on the input or output terminals.

• If the CT Analyzer or any add-on device or accessory does not seem to function properly, do not use it anymore. Please call the OMICRON hotline.

Power Supply• Supply the CT Analyzer only from a power outlet that is equipped with

protective ground (PE).

• Instead of supplying the CT Analyzer from phase-neutral (L1-N, A-N), it may also be supplied from phase-phase (e.g. L1-L2, A-B). However, the voltage must not exceed 240VAC.

• If there is a problem with the PE (protective earth) connection or if the mains power supply has no galvanic connection to earth, the CT Analyzer displays the error message 901. If you ignore this error message, it is possible to use the device but safety is no longer given!

Note: Even if you switched off the CT Analyzer, wait until all LED lights are fully extinguished.

As long as an LED lights or the display is on, there may still be voltage and/or current potential on one or more of the CT Analyzer outputs.

Safety Instructions for CT Analyzer

13

Changing Fuses• Turn off the CT Analyzer and unplug the power cord.

• Ground the test object, and disconnect it from the CT Analyzer. By disconnecting it you prevent a possibly faulty test object feeding power back into the CT Analyzer.

• Locate the blown fuse on the side panel of the CT Analyzer and replace it:

2 x T6.3H 250V (6.3 Amps slow-acting high breaking capacity wire fuse 5x20mm).

6 Safety Rules for Your Own Safety

CAUTION: When working without a proper PE connection, lethal voltages can occur at the housing and all inputs/outputs.

If the mains supply does not have proper galvanic connection to PE, voltages higher than the CT Analyzer is built for can occur between mains and other potential groups of the device (refer to section 13.6 on page 219). These voltages can possibly destroy the device.

If you decide to work without proper PE connection you take the risk to become mortally shocked or to destroy the CT Analyzer due to high common mode voltages on the mains input. Make sure to connect at least the equipotential terminal of the CT Analyzer to PE.

Note: Replace with identical fuse type only.

Always observe the following safety rules:

1. Isolate.

2. Secure to prevent reconnecting.

3. Check isolation.

4. Earth and short-circuit.

5. Cover or shield neighboring live parts.

6. Never touch any terminals that are not visibly connected to earth.

CT Analyzer

14

Designated Use and Features

15

1 Designated Use and Features

1.1 Designated UseThe CT Analyzer is intended to perform automatic testing and calibration of low leakage flux current transformers (CTs with non-gapped cores) in laboratories as well as on-site in utilities. The following tests can be performed using the CT Analyzer:

• Burden measurement• CT winding resistance measurement• CT excitation characteristic according to IEC 60044-1, IEC 60044-6 (TPS,

TPX, TPY, TPZ) and IEEE C57.13.• CT ratio measurement with consideration of a connected burden• CT phase and polarity measurement• Determination of accuracy limiting factor, instrument security factor,

secondary time constant, symmetrical short-circuit current factor, transient dimensioning factor, remanence factor, knee point voltage/current, class, saturated inductance and non-saturated inductance.

1.2 Features• Very small and lightweight (< 8kg/17lb), particularly beneficial for on-site

testing.• Reduced commissioning time due to fully automatic testing within seconds.• The test results are displayed in a graphical user interface.• Allows testing according to IEC 60044-1, IEC 60044-6 or IEEE C57.13 (ANSI

standard).• Maximum output voltage = 120V (safety).• Automatic assessment of the test results.• Automatic analysis of CTs with unknown data ("guesser" function). This

means that for CTs defined according to IEC60044-1, testing can be performed without any previous specification of CT data by the user. The CT Analyzer is able to determine the CT data (I-prim, I-sec, class, ratio, etc.) and to assess whether the connected CT fulfills the specifications or not. The guesser function is intended as an aid for the user to find out the data of unknown CTs.

• For measuring transformers: A typical accuracy of 0.02% / 1’ enables field calibration and verification of class 0.1 CTs for metering.

CT Analyzer

16

• For protection transformers: Automatic result assessment according to the defined standard (IEC 60044-1, IEC 60044-6 or IEEE C57.13-1993) using implemented expert knowledge (regarding standards, etc.) even for CTs defined according to IEC 60044-6 with defined transient performance (TPS, TPX, TPY, TPZ).

• Test of CTs with very high knee-point voltages (up to 15 kV).• Measurement of the following CT parameters:

General:

– Ls (saturated inductance)

– Lm (unsaturated inductance)

– Kr (remanence flux)

– Ts (secondary time constant)

– Rct (winding resistance)

IEC 60044-1

– ALF (accuracy limiting factor acc. to direct measurement method)

– ALFi (accuracy limiting factor acc. to indirect measurement method)

– FS (instrument security factor acc. to direct measurement method)

– FSi (instrument security factor acc. to indirect measurement method)

– Kx (dimensioning factor according to class PX)

– Ek (accuracy limiting voltage according to class PX)

– Ie (accuracy limiting current according to class PX)

– N (turns ratio according to class PX)

– εt (turns ratio error)

– εc (composite error)

– Vkn (knee-point voltage according to IEC 60044-1)

– Ikn (knee-point current according to IEC 60044-1)

– current ratio error and phase error for all measurement points defined in the standard

IEC 60044-6

– Kssc (rated symmetrical short-circuit current factor)

– Ktd (transient dimensioning factor)

– N (turns ratio according to class TPS)

– εt (turns ratio error according to class TPS)

Designated Use and Features

17

– ε^ (peak instantaneous error)

– Emax (maximum emf voltage incl. the transient component)

– Vkn (knee-point voltage according to IEC 60044-6)

– Ikn (knee-point current according to IEC 60044-6)


IEEE C57.13 (ANSI)

– Vb (secondary terminal voltage rating according to IEEE C57.13)

– Vkn (knee-point voltage according to IEEE C57.13 (30° and 45° tangent))

– Ikn (knee-point current according to IEEE C57.13 (30° and 45° tangent))


• Almost unlimited in:– Ratio (50 000 : 1)

– Primary current (999 000A max.)

– Knee point voltage (15kV max.)

• Precise measurement of ratio error and phase displacement up to x-times the rated current and for all burden values without the need to connect burden hardware, independent of the application (e.g. bushings and GIS).

• Automatic demagnetization of the CT after the test.• Data storage on a removable Compact Flash (CF) card which can be read by

any standard memory card reader.• Automatic test report generation. Viewing and printing of test reports on a PC

using the CPC Explorer.• Existing test reports can be loaded at any time to recalculate the test results

for different burden values and primary currents. This way, no further on-site measurements are necessary to verify whether a changed burden influences the behavior of a CT. The recalculation of the test results can be performed easily in the laboratory using the existing measurement data either on the CT Analyzer, within the CTA Remote Excel File Loader or by using the CTA Remote Control software.

• PC Tool (CTA Quick Test) for a large variety of measurements usually necessary in a utility using the CT Analyzer as a multimeter with integrated current/voltage source (measurement of burden, L, C, ratio, polarity, etc.).

CT Analyzer

18

• Remote interface enabling the integration of the CT Analyzer into automatic production processes. The CT Analyzer can be controlled completely via the remote interface. All parameters can be read from the device or from a test report with an easy to use software interface.

• Possibility to create user defined test reports using the CTA Remote Excel File Loader or by adaption of sample software running under visual basic or C++.

Hardware

19

2 Hardware

2.1 Functional Components of the CT Analyzer2.1.1 Overview

Figure 2-1 provides an overview of the operating and display elements and the connectors of the CT Analyzer.

Figure 2-1:CT Analyzer overview Output

Generator outputDisplay

with context-dependent keys ("soft keys")

Remote control interfaceSerial interface for full

remote control (see 13.8)

Sec, PrimMeasurement inputs

I/0 keywith status LEDs

Mains connection unitMains socket with fuse and

ON/OFF switch

Compact Flash card slot

Keyboardwith cursor keys and card selection keys

Equipotential connector

CT Analyzer

20

2.1.2 Mains Connection Unit and GroundingFigure 2-2:Mains connection unit and equipotential bonding connector

2.1.3 Compact Flash Card SlotFigure 2-3:Compact Flash card slot

Mains socket (IEC320)

ON/OFF switch

Equipotential bonding connector (4mm socket combined with knurled nut for clamp connection)

Mains fuse: 2 x T6.3A / 250V, high breaking capacity

Compact Flash card

Storage medium for test data.

Eject button

Press to eject the Compact Flash card.

Hardware

21

2.1.4 Inputs and OutputsWhile the red LED of the I / 0 key is flashing, voltage is applied at the output and the measurement inputs.

Figure 2-4:Inputs and outputs of the CT Analyzer

2.1.5 I/0 Key with Status LEDs

Output

Generator output, 120V/15A peak max.

Sec

Measurement input for secondary side of CT, 300VAC max., 500 kΩ input impedance

Prim

Measurement input for primary side of CT, 30VAC max., 150 kΩ input impedance

Red LED (on the left).Green LED (on the right).

I/0 key to start the test.

During the boot process after switching the CT Analyzer on, both LEDs are on. The red LED is switched off when the boot process is finished and the CT Analyzer is ready for operation.

Green LED on: The CT Analyzer is switched on and ready for operation.

Red LED flashing: Test is running. While the red LED is flashing, voltage is applied at the output and the measurement inputs.

Red LED steadily on: Device error.

CT Analyzer

22

2.1.6 DisplayFigure 2-5:Display Card area with tab Soft key description

fieldsSoft keys, labelled by the soft

key description fields

If 3 points are visible in the lowest soft key description field (see dashed arrow), this key can be used to open an additional set

of soft keys

Edit fields(underlined by dotted lines)

Status line

Display field(not underlined)

A scrollbar is displayed, if the content of a card is too long to be displayed at a time.

Use the CURSOR UP / DOWN keys on the keyboard to scroll through the card.

Hardware

23

2.2 Block Diagram (Simplified)Figure 2-6:Simplified block diagram of the CT Analyzer

Overtemp,overload

Current Shunt

EMC filterBandwithlimiter

Current measurement

and relay control

Control for current measurement

Relay control and temperature read

Sec

0...300VAC

Duty cycle control

Bridge control

EMC filter

Gain adjust

Gain control

EMC filter

Gain adjust

Analoginput data

Range switching

control signals

Keyboard

LAMP

LCD (240x128)

ON/OFF

Contrast-adjust

Inverter

ON/OFF

AD-converter

AD-converter

Gain control

Co

ntr

olS

ign

als

Digital Signal

Processing

RI 300V

RI 300V

Prim

0..30VAC

Display Unit and

Keyboard (DUK)

MIF

RI 300V

Remote Control Interface

Output

0...120V max.

SELV Potential

Tem

pdete

ct

250V 10A T

N

L

PE

Mains Filter

L

N

Boost converter

85-265VAC

360VDC

IEC 320 with Filter

Mains Potential

RI: 400V to all other

potential groups

120VDC

360VDC

+360V

-360V

RI

RI

RI = Reinforced insulationBI = Basic insulation

CT Analyzer

24

Connecting the CT Analyzer

25

3 Connecting the CT Analyzer

3.1 Basic Wiring for a Burden TestFor a burden test, connect the CT Analyzer as shown in figure 3-1.

Figure 3-1:Basic wiring for a burden test

• Connect the CT Analyzer’s equipotential terminal to protective earth (PE).

• Open the connection line to the ungrounded side of the CT (refer to figure 3-1). Otherwise, the CT Analyzer would measure the parallel impedance of the burden and the CT winding instead of the burden itself.

• Connect the black sockets of the CT Analyzer "Output" and input "Sec" to that side of the burden that is connected to PE.

• Connect the red sockets of the CT Analyzer "Output" and input "Sec" to the other (ungrounded) side of the burden.

If you do not disconnect the CT for the burden test, the CT Analyzer measures the parallel impedance of the burden and the CT winding. Although in many cases the impedance of the CT is many times higher than the burden impedance, this will cause a measuring error.

The CT Analyzer does not perform a demagnetizing cycle after burden measurement. Therefore, CT saturation could occur, if you do not disconnect the CT prior to the burden test.

CT Burden

CT Analyzer

26

3.2 Basic Wiring for a CT TestThis section shows the basic wiring of the CT Analyzer for a CT test. For a detailed description how to connect the CT Analyzer for specific applications, please refer to chapter 7 ”Application Examples” on page 143.

The grounded terminal on the secondary side of the CT always has to be connected to the black sockets of input "Sec" and the "Output" of the CT Analyzer. Connecting the red sockets of the CT Analyzer to PE can result in incorrect measurement and/or cause an automatic abortion of the measurement with an error message.

If it is necessary to use clamps for the connection of the measurement leads to the secondary side of the test object, always use the 4 wire connection technique as described in section 3.3 on page 28 in order to avoid measurement errors.

For a CT test, connect the CT Analyzer as shown in figure 3-2.

Figure 3-2:Basic wiring for a CT test


Utility line Prevent coupling of interferences into the primary circuit!

Coupling of interferences into the ungrounded connection influences the measurement results.

The side that is able to receive more interferences has to be connected to PE.


27

• Make sure that the primary side of the CT is connected to PE on one side and open on the other side.

It is absolutely important to avoid coupling of interferences into the primary circuit during measurement. Therefore, connect the side of the primary circuit that is able to receive more interferences to PE (e.g. the side with the longer line length). The ungrounded side should be the side that receives fewer interferences (refer to figure 3-2).

• Disconnect the hot side of all secondary windings of the CT in order to remove any load from the CT. Every kind of load remaining on the secondary side of the CT during measurement leads to incorrect measurement results or error messages.

• Connect the black socket of the CT Analyzer input "Prim" to the grounded side of the CT’s primary circuit and the red socket of this input to the open (ungrounded) side.

• Connect the black sockets of the CT Analyzer "Output" and input "Sec" to that terminal on the secondary side of the CT that is connected to PE.

• Connect the red sockets of the CT Analyzer "Output" and input "Sec" to the other (ungrounded) terminal on the secondary side of the CT.

CT Analyzer

28

3.3 4 Wire Measurement vs. 2 Wire MeasurementIf the secondary side of the test object does not provide screw terminals for connecting the delivered terminal adapters or banana sockets to insert the measurement leads directly, and it is therefore necessary to use clamps (e.g. crocodile clamps or Kelvin clamps) for the connection of the measurement leads, always use the 4 wire connection technique as described below.

Otherwise, the possibly existing contact resistance of the clamp could affect the measurement results, i.e., the CT Analyzer possibly delivers incorrect measurement results.

Both connection techniques are shown in the following figure.

Figure 3-3:Demonstration of 2 wire and 4 wire connection technique

4 wire connection:The measurement leads from the "Output" sockets and input "Sec" of the CT Analyzer are connected to the test object via separate clamps.

One clamp is used for each measurement lead! Correct!

2 wire connection:Separate measurement leads are used for the "Output" sockets and input "Sec" of the CT Analyzer, but the measurement leads are connected to the test object via a common clamp.

Two measurement leads use one single clamp! Do not use!

XDo not use!

OK


29

Physical BackgroundWhen using the 2 wire connection technique as shown in figure 3-3, considerable measurement errors for the ratio error and other parameters can occur, if the connection of the clamp to the test object is not ideal and has a contact resistance. Since this contact resistance will change with each connection/disconnection of the clamp at the test object, it is furthermore not possible to reproduce such measurements.

The total contact resistance caused by 2 clamps can be up to 0.5 ohms and thus can cause an additional burden of up to 12.5 VA. Due to this, the influence of the contact resistance is the higher the smaller the winding resistance of the CT is: When measuring a 5 A CT, such a contact resistance can lead to completely incorrect measurement results while it is practically negligible when measuring a CT with a relatively high winding resistance of e.g. 10 ohms.

Therefore, measurements on 5 A CTs should exclusively be performed using the 4 wire connection technique!

The following connection diagrams make this clear.

Figure 3-4:Connection diagram for 4 wire connection technique

~

OUTPUT

SEC

Ip

P1

P2 S2

S1

Np NsUC IL

RH

Lmain

IC

Reddy

IE

ICT

RCTRcl.

Rcl.

Voltage drop caused by contact resistance of the clamp

Term

inal

vol

tage


4 wire connection:Input "Sec" of the CT Analyzer measures the terminal voltage of the test object. The measurement is not influenced by the voltage drops caused by the contact resistance of the clamps. The measurement results delivered by the CT Analyzer are correct!

CT Analyzer

30

Figure 3-5:Connection diagram for 2 wire connection technique

~

OUTPUT

SEC

Ip

P1

P2 S2

S1

Np NsUC IL

RH

Lmain

IC

Reddy

IE

ICT

RCTRcl.

Rcl.


Term

inal

vol

tage

Vol

tage

beh

ind

the

clam

p


2 wire connection (do not use!):Input "Sec" of the CT Analyzer does not measure the terminal voltage of the test object! It only measures the voltage behind the clamps instead, and thus includes the voltage drops caused by the contact resistance of the clamps.

The measurement results delivered by the CT Analyzer are possibly incorrect!

Running an Automatic Parameter Search and CT Test (Guesser Function)

31

4 Running an Automatic Parameter Search and CT Test (Guesser Function)If you are not familiar to operating the CT Analyzer, you should read chapter 5 before taking the CT Analyzer into operation and/or running tests with the CT Analyzer.

For standard current transformers built according to IEC 60044-1 and IEEE C57.13, the CT Analyzer offers an excellent possibility to do a test with minimal training and without any knowledge of the CT to be tested.

For a flow chart of the parameter search function for the class determination, refer to section 10.18 on page 198. For a flow chart of the burden guesser function, refer to section 10.19 on page 204.

4.1 Connecting the CTConnect the CT to the CT Analyzer as shown on the front panel. Be sure that the polarity of all wires is correct.

1. Secondary side of the CT to input "Sec" and "Output" of the CT Analyzer.

2. Primary side of the CT to CT Analyzer input "Prim".

4.2 Preparing the TestIf the CT Analyzer is already switched on:

1. If necessary, display the CT-Object card and then press the M A I N soft key to display the main menu.

2. Select the list item "New CT Test" and press the O K soft key to initialize a new CT test.

3. The display shows the CT-Object card, ready to start a test.

Note: Although the CT Analyzer is able to determine the CT’s data (I-prim, I-sec, class, ratio, etc.) and to assess whether the connected CT fulfills the specifications or not, the guesser function is only intended as an aid for the user to find out the data of unknown CTs. The data and values determined by the CT Analyzer using the guesser function are not guaranteed and have to be verified by the user.

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32

If the CT Analyzer is switched off:

1. Switch the CT Analyzer on.

2. After the boot process is finished, the green LED is on and the red LED is off.

3. The display shows the CT-Object card, ready to start a test.

4.3 Running the Test

Starting the testAfter switching the CT Analyzer on or after initializing a new test from the main menu, the default CT-Object card is displayed.

Figure 4-1:Empty CT-Object card

Start the test by pressing the I / 0 key. The red LED flashes to indicate that the test is running.

Test step 1: CT resistance measurementThe CT Analyzer measures the secondary winding resistance of the CT.

Figure 4-2:Resistance card with measurement results

For a detailed description of this card, please refer to page 56.


Running an Automatic Parameter Search and CT Test (Guesser Function)

33

Test step 2: Determination of the excitation characteristicThe CT Analyzer measures the excitation curve and determines the knee point and other important CT data. Depending on the knee point voltage, the CT Analyzer decides whether the connected CT is a measurement CT or a protection CT (see also the flow chart in section 10.18 on page 198). With the knee point, the burden guesser function can also be started (see section 10.19 ”Guesser Algorithm for Burden” on page 204).

Figure 4-3:Excitation card with measurement results

Test step 3: Ratio measurementThe CT Analyzer then measures the current ratio error, the phase error, the composite error and the polarity. The CT Analyzer calculates the ratio error for the operating burden (parameter "Burden" in the CT-Object card) and the nominal burden (parameter "VA" in the CT-Object card).

To view the measurement results based on the operating burden, open the Ratio card using the card selection keys.

Figure 4-4:Ratio error and phase displacement at operating burden



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Test step 4: After the test is finishedAfter the test is finished, the CT-Object card displays the CT data determined during the test (refer to figure 4-5).

Figure 4-5:CT-Object card after the test is finished

Now you can enter the "Location" and "Object" details and save the test.

The CT Analyzer also performed an automatic assessment of the measured results using the guessed parameters. This assessment can be viewed on the Assessment card (figure 4-6). For a detailed description of this card, please refer to section 5.9 on page 96.

Figure 4-6:Assessment card after the test is finished

User Interface and Operation

35

5 User Interface and Operation

5.1 Introduction and Basic Operating Procedures5.1.1 Overview of Test Cards

The following table provides an overview of the available test cards:

Table 5-1:Overview of available test cards Card Usage

CT-Object The CT-Object card contains the basic CT data and is always required to perform a CT test.

Refer to page 56 for a detailed description of this card.Burden The Burden card is used to measure a current transformer’s

secondary burden with AC current.

Refer to page 72 for a detailed description of this card.Resistance The Resistance card is used to measure the DC resistance

of the secondary winding.

Refer to page 75 for a detailed description of this card.Excitation The Excitation card is used to trace the excitation curve of

the current transformer and to determine further CT-specific parameters.

Refer to page 77 for a detailed description of this card.Ratio The Ratio card is used to measure the current ratio of the CT

considering the external load or the nominal burden and to determine the current ratio error and the phase displacement.

Refer to page 90 for a detailed description of this card.Assessment The Assessment card shows the automatic assessment of

the tested parameters according to the selected standard. In this card you can also perform a manual assessment.

Refer to page 96 for a detailed description of this card.Comment In the Comment card you can enter any text, e.g. additional

notes regarding the test.

Refer to page 107 for a detailed description of this card.

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5.1.2 Working with the User Interface

Displaying a specific cardTo display a specific card, select the card by pressing the card selection keys on the keyboard. The card’s tab showing the name of the selected card is then highlighted (see figure 5-1).

Figure 5-1:CT-Object card selected

Using the soft keysUsing the soft keys you can operate the CT Analyzer and change the user interface level of the software.

The functionality of the soft keys is context-dependent, i.e., the software offers different functions or selectable sets of parameters depending on the focus (i.e., depending on which card or field is highlighted or selected in the user interface).

If the lowest soft key description field contains 3 points (see S A V E A S in figure 5-1), additional soft key functions are available. Then you can switch the set of displayed soft keys using the . . . key located below the soft keys (see figure 5-2).

Figure 5-2:Switching the set of soft keys in the CT-Object card

1st set of soft keys

Press

2nd set of soft keys


37

Editing a cardTo open the edit mode for a displayed card, press the C U R S O R D O W N key on the keyboard. The card’s tab is then no longer highlighted (see figure 5-3).

Use the cursor keys to move the cursor and to select the desired edit field. Some edit fields have soft keys assigned. The soft keys available for an edit field are displayed if the field is selected.

Figure 5-3:Edit field selected in CT-Object card

Proceed as follows to edit a card:

• Select the edit field using the cursor keys.

• Enter or edit the value or text:

– Either select an entry offered by the soft keys (if available)

– or enter the value or text using the keyboard and then press the E N T E R key to confirm your input or use the E S C key to leave an edit field without applying and saving the entry.

• Leave the edit mode either by moving the cursor to the card’s tab using the C U R S O R U P key or by pressing the E S C key on the keyboard. The focus is then set to the card’s tab again (tab highlighted).

Display field(cannot be selected)

Edit field

Edit field, selected

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5.2 CT Analyzer Help SystemThe CT Analyzer provides a context-sensitive help system. I.e., if you press the H E L P button on the keyboard, a help page is displayed, the content of which depends on where the focus was set before the H E L P button was pressed.

For example:

• If the focus is set to the CT-Object card’s tab, pressing the the H E L P button displays a help page showing the wiring for a CT test.

• If the focus is set to the Burden card’s tab, pressing the the H E L P button displays a help page showing the wiring for a burden test.

• If a parameter field in the CT-Object card or the Assessment card has been selected with the cursor, pressing the the H E L P button displays a help page with explanatory texts for this specific parameter.

Figure 5-4:Help system showing the wiring diagram for the CT test

Figure 5-5:Help system showing explanatory help text for a parameter

When the help system is displayed, you can use the soft keys N E X T P A G E and P R E V. P A G E to scroll through the available help pages.

Pressing the A B O U T soft key opens a page with information about the CT Analyzer hardware, the installed firmware, the serial number, etc.


39

Figure 5-6:Help system showing the wiring diagram for the CT test

The coding of the hardware version (e.g. 00/00/07/01/00/06) is described below:

aa/bb/cc/dd/ee/ff

aa Version of the power supply module.

bb Version of the measurement interface.

cc Version of the programmable gate array on the measurement interface.

dd Version of the programmable gate array on the DSP.

ee Version of the DSP (Digital Signal Processor).

ff Version of the firmware on the measurement interface:xx (for MIF), xx (for FPGA), DSP Max version, DSP-Ver./xxx (AVR SW version)

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5.3 Main MenuThe Main Menu can be opened from any test card by pressing the M A I N soft key.

The items in the list can be selected using the cursor keys. When an item is selected (highlighted), the soft keys are labelled with the functions available for this specific item.

Figure 5-7:Main menu, "New CT-Test" selected

5.3.1 New CT-TestBy selecting "New CT-Test" in the main menu and then pressing the soft key O K , a new CT test with the default parameter settings is loaded and displayed in the CT-Object card. Some of the default values can be defined in the "Default Test Settings".

Figure 5-8:CT-Object card with default test settings

The following table shows the default settings after initiating a new CT test.

Note: For more detailed information about the parameters and fields in the CT-Object card, please refer to section 5.4.3 on page 58.


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Table 5-2:Default settings for a new CT test

Parameter Description Default valueLocation

and

Object

Information about the location of the CT (e.g. company, country, station, etc.) and the CT (e.g. manufacturer, type, serial no., etc.).

The content of these fields is defined in the Location settings page and the Object settings page, respectively (opened by pressing the D E T A I L S soft key displayed when the cursor is positioned in these fields).

For more detailed information, please refer to section 5.4.2 on page 57.

not changed

I-pn Rated primary current. "?"1

I-sn Rated secondary current. "?"1

Standard Standard according to which the test has to be performed.

As defined in the default test settings

P/M Protection or measurement CT. "?"1

Class Class definition for the CT. "?"1

FS Instrument security factor.

Only applicable for: IEC 60044-1, measurement CTs.

"?"1

ext Rated continuous thermal current Ith.

Only applicable for: IEC 60044-1, measurement CTs.

120%

RF Thermal current rating factor.

Only applicable for:ANSI 30/45 measurement CTs.

2

Vb Secondary terminal voltage.

Only applicable for:ANSI 30/45 protection CTs.

"?"1

ALF Accuracy limiting factor.

Only applicable for:IEC 60044-1 classes P and PR.

"?"1

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Ts Specified secondary time constant.

Only applicable for: IEC 60044-1 class PR,IEC 60044-6 classes TPY and TPZ

"?"1

Kx Specified dimensioning factor.

Only applicable for: IEC 60044-1 class PX.

"?"1

Ek Specified accuracy limiting voltage.


"?"1

Ie Specified accuracy limiting current.


"?"1

E1 User-defined e.m.f. to verify the excitation current at this specific e.m.f.

Only applicable for: IEC 60044-1 class PX,IEC 60044-6 class TPS.

"?"1

Ie1 Maximum allowed excitation current at E1.

Only applicable for: IEC 60044-1 class PX,IEC 60044-6 class TPS.

"?"1

Kssc Symmetrical short-circuit current factor.

Only applicable for IEC 60044-6."?"1

Tp Primary time constant.

Only applicable for IEC 60044-6.

0.02s

K Specified dimensioning factor.

Only applicable for IEC 60044-6 class TPS.

7.28

V-al Specified accuracy limiting voltage.

Only applicable for IEC 60044-6 class TPS."?"1

I-al Specified accuracy limiting current.

Only applicable for IEC 60044-6 class TPS."?"1

Parameter Description Default value


43

Ktd Rated transient dimensioning factor.

Only applicable for:IEC 60044-6 classes TPX, TPY and TPZ.

"?"1

Duty Duty cycle.

Only applicable for:IEC 60044-6 classes TPX and TPY.

CO

t1, t2 Specified duration of first and second current flow.


0.1s

t-al1, t-al2 Specified accuracy limiting time of first and second current flow.


0.04s

tfr Specified dead time during auto reclosing.

Only applicable for:IEC 60044-6 classes TPX and TPY, duty cycle COCO.

0.3s

f Rated frequency. As defined in the default test settings

Rct Rated secondary winding resistance at 75°C.

"?"1

Ktd calculation Defines whether the transient dimensioning factor Ktd is calculated acc. to IEC 60044-6 (without consideration of the remanence) or acc. to the OMICRON method (with consideration of the remanence).

Only displayed for IEC 60044-6 classes TPX and TPY.

acc. to IEC 60044-6 (remanence not considered)

VA Rated power of the CT. "?"1

Cosϕ Cosϕ of the nominal burden. "n/a"

Burden Operating burden of the CT. "?"1

Cosϕ Cosϕ of the operating burden. "?"1


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5.3.2 File HandlingBy selecting the item "File Handling" in the main menu all file operation functions can be accessed using the C U R S O R U P/ D O W N keys and the S E L E C T soft key.

Figure 5-9:File Menu

Available functions

Class mult. factor

This factor increases the assessment level for the ratio test. E.g. a class multiplier of 0.5 means that the maximum accepted tolerance for the ratio error is only half the standard tolerance.

1.0

Delta compensation

Correction factor for the ratio measurement.

Ratio 1

1. Parameters indicated as "?" will be guessed during the test.


Load Report Loading an existing report or settings file from the Compact Flash card.Note: You can also load a file by pressing the L O A D soft key in the CT-Object card.

Save As Saving the current file to the Compact Flash card. Saving a file is described in detail on page 47.

Rename File Renaming a selected file on the Compact Flash card.

Only files can be renamed. Renaming of folders is not possible with the CT Analyzer.


45

Delete File Deleting a selected file or folder from the Compact Flash card.

Only empty folders can be deleted. If you try to delete a folder still containing files or subfolders, an error message is displayed.

To select several neighboring files at a time, keep the S H I F T key on the keyboard pressed while selecting the files or folders using the C U R S O R U P / D O W N keys.

Copy / Cut / Paste File(s)

Copying or cutting a file on the Compact Flash card and pasting it at another location on the Compact Flash card.

Copying/cutting and pasting a file is described in detail on page 47.

Format CF card Formatting the Compact Flash card. All data on the Compact Flash card will be lost!

Note: In the CT Analyzer file system, the root directory can contain a maximum of 240 files and the maximum file name length is 240 characters.

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46

Working with the file systemAfter selecting one of the available file operation functions in the File Menu, the file system card is displayed showing the current path in its title bar and the file system elements in the card area (refer to figure 5-10).

Navigating in the file system• To open a folder, select its entry (see figure 5-10, left) using the cursor keys

and then press the E N T E R key.

• To go one level higher in the directory structure, select the "one level back" entry (see figure 5-10, right) and then press the E N T E R key.

Figure 5-10:File system card

Creating a new folder To create a new folder, open the main menu and select the item "File Handling". Select "Save As" to open the file system card and then navigate to the desired location in the file system where you want to create the new folder. Then press the N E W D I R soft key. A new folder with an empty name is created. Enter a name for the folder and press the E N T E R key.

Figure 5-11:Creating a new folder

Note: In the CT Analyzer file system, a directory can contain a maximum of 240 files and the maximum file name length is 240 characters.


47

Saving a file1. To save a file, open the main menu and select the list item "File Handling". In

the appearing File Menu, select the item "Save As".

2. Navigate to the desired folder in the file system where you want to save the file:

• If you like to save the file with the same name press the S A V E soft key. A warning window will pop up asking whether the existing file should be overwritten or not.

• If you want to use a similar file name as an existing one in the selected folder, select this file using the cursor keys and press S A V E A S or E N T E R. A new *.xml file entry with the selected file name is added. Edit this file name and then press again S A V E , S A V E A S or E N T E R.

Copying / cutting and pasting a file

1. To copy or cut a file on the Compact Flash card and paste it at another location in the file system, open the main menu and select the list item "File Handling". In the File Menu, select the item "Copy File(s)" or "Cut File(s)".

2. The file system card appears. Navigate to the desired file you want to copy or cut.

3. Highlight the file and then press the C O P Y (or C U T) soft key.

To go back to the main menu without copying or cutting a file, press A B O R T .

4. The file system card is closed and the File Menu is displayed. Select the list item "Paste File(s)".

5. The file system card appears again. Navigate to the desired location in the file system where you want to paste the file.

6. Press the P A S T E soft key to paste the file.

In case of a cut/paste action, the file is not deleted from its old location until it has been pasted at its new location.

Note: You can also save a file by pressing the S A V E or the S A V E A S soft key in the CT-Object card.

Note: Copying / cutting and pasting of folders is not possible with the CT Analyzer.

Note: To select several neighboring files at a time, keep the S H I F T key on the keyboard pressed while selecting the files using the C U R S O R U P / D O W N keys.

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5.3.3 SettingsTo change the device settings or the test settings for a new CT test, select the list item "Settings" from the main menu.

Figure 5-12:Main menu, "Settings"

Available items in the Setting MenuSelect Language Selection of the user interface language.

A maximum of two languages can be installed on the CT Analyzer. The English user interface is part of the firmware and therefore always available. The second language can be installed by the user as required (refer to section 5.3.4 on page 52).

Default Test Card Selection

Select the test cards a new CT test should contain by default. Please refer to the corresponding subsection below.

Default Standard Standard to be used for a new CT test.

Possible values: IEC 60044-1, IEC 60044-6, ANSI 30, ANSI 45.

ANSI 30 and ANSI 45 represent the standard IEEE C57.13 with knee-point calculation either for 30° or 45° tangent.

Use the C U R S O R U P/ D O W N keys to scroll through the list.


49

Default Nominal Frequency

Nominal frequency to be used for a new CT test.

Possible values: 16.7 Hz, 50 Hz, 60 Hz.Ktd Calculation Select whether the Ktd (transient dimensioning factor)

acc. to IEC 60044-6 is calculated exactly according to the standard or whether the calculation considers the CT remanence (refer to section 10.17 ”Determination of Transient Dimensioning Factor (Ktd)” on page 196).

Temperature Unit Selection of the temperature unit (°C or °F).Ambient Temperature

Default measurement temperature for winding resistance measurement.

Possible values: -40 to 150°CDate/Time Clock settings for the device-internal clock.Display Contrast Display contrast adjustment.K-Value Error Graph

Enable or disable the K-value error graph.

This graph is primarily required for Chinese standards. It shows the maximum possible primary current (K * Ipn) that can flow over a specific burden without exceeding the accuracy limit (5% or 10%).

Start Delay Allows the definition of a delay time of up to 10s for the test start after pressing the start button.

Misc. Settings In the "Miscellaneous Settings", the thresholds for the decision algorithms of the guesser function can be defined:

• "Decision 1A/5A CT"

• "Decision P/M CT" (values "Prot. CT, if V-kn >" for 1A and 5A CT)

• "Multiplying factor" for ratio error assessment

Please refer to the corresponding subsection below.

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Default test card selectionTo open the Select Cards page, select "Default Test Card Selection" in the main menu and then press the S E L E C T soft key.

Figure 5-13:Selecting default test cards

1. To enable or disable a card, select its entry using the C U R S O R U P / D O W N keys and then press the A D D or R E M O V E soft key. Enabled cards are marked with a checkmark.

Some cards require the existence of other cards. This means that if you are adding such a card, the required other cards are automatically added, too. On the other hand, if you remove a card which is required by another card, the other card is removed, too. The following table shows these dependencies.

Table 5-3:Dependencies between test cards

To save your selection and return to the Setting Menu press the B A C K soft key. To return to the Setting Menu without saving the selection, press the E S C key.

This card ... ... requires the existence of:

CT-

Obj

ect c

ard1

1. The CT-Object card is always required to perform a CT test.

Bur

den

card

Res

ista

nce

card

Exci

tatio

n ca

rd

Rat

io c

ard

Ass

essm

ent c

ard

Com

men

t car

d

Burden card xResistance card xExcitation card x xRatio card x x xAssessment card xComment card x


51

Miscellaneous SettingsFigure 5-14:Miscellaneous Settings

The following values can be defined in the "Miscellaneous Settings" page:

• "Decision 1A/5A CT"

If the guesser function is active, the device uses the measured winding resistance to decide whether the CT is a 1A or 5A CT. This value specifies the decision threshold.

Possible values: 0.5 to 2ΩDefault value: 1ΩIf measured winding resistance > defined value, the guesser function decides that the CT’s nominal secondary current is 1A.

If measured winding resistance < defined value, the guesser function decides that the CT’s nominal secondary current is 5A.

• "Decision P/M CT"

If the guesser function is active, the device uses the measured knee-point voltage to decide whether the measured CT is a protection CT or a measurement CT. This value specifies the decision threshold.

If knee-point voltage > defined value, the guesser function decides that the measured CT is a protection CT. Otherwise it is a measurement CT.

"1A: Prot. CT, if V-kn >"Possible values: 50 to 300V Default value: 100V

"5A: Prot. CT, if V-kn >"Possible values: 15 to 60VDefault value: 20V

• "Class mult. factor"

The default value for the class multiplying factor can be set. This default is used when the CT Analyzer is switched on or if a new CT test is selected in the main menu. The class multiplying factor increases the assessment level for the ratio test.

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52

E.g. a class multiplier of 0.5 means that the maximum accepted tolerance for the ratio error is only half the standard tolerance (all ratio tolerance values are multiplied with the entered factor).

Possible values: 0.25 to 1.00Default value: 1.00

The R E S E T V A L U E S soft key resets all values to their default values.

5.3.4 ToolsUsing the item "Tools" in the main menu you can access the update functions of the CT Analyzer.

Figure 5-15:Main menu, "Tools"

Available functions

Note: Instead of using the CT Analyzer functions "Update Text" and "Update Firmware" described below you can alternatively use the Firmware Update PC tool contained in the CT Analyzer PC Toolset. For detailed information, please refer to section 6.6 on page 131.

Update Text Using this item you can install a new user interface language file.

The file system page opened after selecting the "Update Text" function only displays files named CTUser*.bin.

Please refer to the following subsection.Update Firmware Using this item you can update the firmware of your

CT Analyzer.

The file system page opened after selecting the "Update Firmware" function only displays files named CTAnalyzer*.bin.

Please refer to the following subsection.


53

Update TextFigure 5-16:Update text

After selecting "Update Text" you can install a new user interface language file. This language is then available for selection in the "Language" page.

To install a new language, select the corresponding file CTUser_xxx.bin in the directory A:\OMICRON\ on the Compact Flash card using the C U R S O R U P / D O W N keys and press the S E L E C T soft key.

Update Licenses This function allows to add additional licenses to your CT Analyzer.

Using the U P D A T E L I C E N S E soft key you can read a license file from the Compact Flash card.

Using the N E W L I C E N S E soft key you can add new licenses manually.

For information how to receive new licenses or a new license key for additional functions, please contact your local OMICRON distributor or the OMICRON support.

Reset to Fact. Calibration

This function is intended for future use.

It allows to restore the factory calibration data.

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English is contained in the firmware and does not require a user language file.

If the text update process is interrupted or fails, the device displays an error message and automatically resets the user interface to English when it is switched on the next time.

Press A B O R T to return to the Tools Menu without installing a new language.

Update FirmwareFigure 5-17:Update firmware

To update the firmware, insert a Compact Flash card containing a file CTAnalyzer*.bin in the directory A:\OMICRON\.

After selecting "Update Firmware" in the Tools Menu, the file system opens, displaying all firmware files available in the directory A:\OMICRON\.

To update the firmware, select the desired firmware file CTAnalyzer*.bin using the C U R S O R U P / D O W N keys and press the U P D A T E F I R M W. soft key.

Attention: Only install language files that are included in the package of the installed firmware version.

If you install a language file that does not belong to the same package, the user interface may become unreadable.

Note: Refer to the OMICRON website for available languages or ask your distributor for a special language file.

Note: The firmware update process may take some minutes. If the update process is interrupted or fails, switch the CT Analyzer off and on again. The device then tries to perform the firmware update again automatically.


55

Press A B O R T to return to the Tools Menu without updating the firmware.

Attention: It is possible to install older firmware. In this case, the user interface text is deleted and the device automatically changes to the English user interface. After you have downgraded the firmware, you also have to install the user interface language file of this (older) firmware package.

After an installation of new firmware, the user interface language automatically changes to English, if the installed user interface text is no longer compatible. If you are using a user interface language other than English, install the corresponding new user interface language file delivered with the new firmware.

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5.4 CT-Object CardThe CT-Object card is the most important card and always required for all types of tests. In this card all necessary settings for a test are done.

Some of the settings contained in the CT-Object card are also shown in other cards for information.

Figure 5-18:Default CT-Object card after loading a new test

5.4.1 Available Soft Keys

Note: The CT-Object card is the top user interface level. Pressing the E S C key several times will always bring you back to the CT-Object card.

Clears the results of the previous test and enables to start a new test.

All measurement results as well as all the parameters previously determined using the "guesser function" are cleared.

Text entries in the fields "Location" and "Object" remain unchanged.

Saves the test results and test settings to the currently loaded CT Analyzer report file. If the test results have not been saved yet, the S A V E A S dialog is opened. Saving a file is described on page 47.

Saves the test results and test settings to a new .xml file. Saving a file is described on page 47.

Allows to load a test stored on the Compact Flash card in order to check its results, to recalculate the results with different settings or to use its settings for a new test.

Note: Recalculation of the existing CT test results in order to verify the behavior of the CT at different burdens or primary currents can be performed by changing the burden value on the CT-Object card or the primary current on the Ratio card. The recalculated results can then be stored again like for a regular test.


57

5.4.2 Information Fields to be Filled by the UserFigure 5-19:Editing the location settings in the CT-Object card

The text fields "Location" and "Object" are only used for reporting and documentation purposes. They can be filled by the user after the test is finished. These fields provide information about the location of the CT and the CT itself. The content of these fields is defined in the Location settings page and the Object settings page, respectively.

To open these settings cards, position the cursor on the "Location" or the "Object" field and then press the D E T A I L S soft key or the E N T E R key.

Table 5-4:Information in the CT-Object card to be filled by the user

Opens the Select Cards page where you can select the test cards for the current test. The Select Cards page is described on page 50.

Attention: When loading a new CT test from the main menu (using the item "New CT-Test"), the test card selection defined in the default test settings is used for this new test. The card selection performed in the CT-Object card will then be discarded.

Card DescriptionLocation settings card

The Location settings page provides the following text fields. Each field can contain a maximum of 40 numbers or letters.

• Company, Country, Station, Feeder: Company, country, station and feeder where the CT is installed.

• Phase: Phase to which the CT is connected.

• IEC-ID: IEC-ID number of the CT or freely definable information.

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5.4.3 Parameters and Settings Used or Determined by the Test ProcessThe CT-Object card fields described in this section are used and/or determined by the test process.

Figure 5-20:Editing the CT-Object card

Parameters and settings displayed for all standards, CT types and classesThe following table 5-5 lists all parameters and settings that are displayed for all standards, CT types and classes. In addition to these common parameters, specific additional parameters are displayed in the CT-Object card depending on the selected standard, CT type (protection or measurement CT) and class. These parameters and settings are described in the following tables 5-6 to 5-15.

Object settings card

The Object settings page provides the following text fields. Each field can contain a maximum of 40 numbers or letters.

• Manufact.: Manufacturer of the CT under test.

• Type: Type number or description of the CT under test.

• Serial No.: Serial number of the CT under test.

• Core: Number of the tested core.

• Tap: Description of the tap (e.g. 1S1-1S3).

• Optional 1: Optional field for free use.

Card Description


59

Table 5-5:Common fields for all standards, used and/or determined by the test

Parameter DescriptionI-pn Rated primary current.

Possible values: 1 to 99000A (keyboard) or ? soft key.Resolution: 0.1ADefault value: "?".If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the nominal primary current. See the flow chart in section 10.18 on page 198.

I-sn Rated secondary current.Possible values: 0.0001 to 10A (keyboard) or soft keys 1 . 0 , 2 . 0 , 5 . 0 , 1 / S Q R T ( 3 ) , 2 / S Q R T( 3 ) , 5 / S Q R T( 3 ) or ? .Resolution: 0.0001ADefault value: "?".If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the nominal secondary current. See the flow chart in section 10.18 on page 198.

Standard Standard according to which the test has to be performed.Possible values: Soft keys 6 0 0 4 4 - 1 , 6 0 0 4 4 - 6 , A N S I 3 0 or A N S I 4 5 . Default value: Standard defined in the default test settings.The standard IEEE C57.13 includes two variants which differ in the definition of the knee point. Therefore either ANSI 30 or ANSI 45 can be selected. For current transformers with non-gapped cores, the knee is defined as the point where the tangent is at 45° (ANSI 45) to the abscissa. For current transformers with gapped cores, the knee is defined as the point where the tangent is at 30° (ANSI 30) to the abscissa.

Note: Using the ANSI 45 standard for transformers with gapped cores may possibly deliver incorrect results.Note: The parameter definition syntax for the different standards is described in chapter 11 on page 207.

P/M Definition of CT type: Protection or measurement CT.Possible values: Soft keys P R O T . C T, M E A S. C T or ? .Default value: "?".If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the CT type to be used. See the flow chart in section 10.18 on page 198.

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60

Class Accuracy class of the CT.Possible values: Depending on the selected standard or ? .The class can be selected by soft keys or is determined during the test by the guesser function. The class guesser function only works for the standards IEC 60044-1 and IEEE C57.13 (ANSI 30, ANSI 45). If the "?" is entered, the device selects the class that first meets the class criteria for the selected standard and type of CT (protection/measurement CT).For a detailed description of the parameter definition syntax, please refer to chapter 11 on page 207.Definition of the "Class" parameter by the user is only possible, if the parameters "Standard" and "P/M" have been defined before. Depending on these parameters, the parameters for the CT class can be selected using the soft keys.If the question mark has been entered for the parameter "P/M", the "Class" cannot be defined by the user but is automatically determined (guessed) by the CT Analyzer during the test instead.

VA

CosϕNominal burden of the CT, used to calculate the behavior of the CT at the nominal burden.Possible values: 0 to 300VA (keyboard) or soft keys 1 . 0 A to 3 0 A or ? to determine the burden using the guesser function (refer to section 10.19 ”Guesser Algorithm for Burden” on page 204).Depending on the guessed burden and the selected test standard, the corresponding cos ϕ is used (cos ϕ not editable by the user):

continued...

Parameter Description

cos ϕ depending on selected nominal burden and standardNominal burden

[VA]

Selected standard

6004

4-1

P

6004

4-1

M

6004

4-1

PX

6004

4-6

C57

.13

(AN

SI)

P

C57

.13

(AN

SI)

M

<5.0 1.0 1.0 1.0 1.0 0.5 0.9>=5.0 0.8 0.8 1.0 1.0 0.5 0.9


61

(cont.) If an ANSI standard is selected (ANSI 30, ANSI 45), the CT Analyzer offers some soft keys (B - 1 , B - 2 , B - 4 , B - 8 ) with standard ANSI loads for the power. If these soft keys are used, the power is calculated according to table 9 in IEEE C57.13. If the rated current is not 5A, the resistance and inductance of the table is multiplied by the following factor:

Burden

Cos ϕ"Burden" and "Cos ϕ" are used to define the operating burden connected to the CT. These parameters are used to calculate the behavior of the CT at the operating burden (connected burden) and the corresponding cos ϕ. Possible values for "Burden": 0 to 300VA (keyboard) or soft keys 1 . 0 A to 3 0 A or ? .

Possible values for "Cos ϕ": 0 to 1 (keyboard).If the "?" was entered or no value was entered, the device tries to guess the operating burden (refer to section 10.19 ”Guesser Algorithm for Burden” on page 204).If the test contains a Burden card, a question mark is automatically entered to the fields "Burden" and "cos ϕ" and entering the burden is not possible until the test is finished. In this case, the value determined during the burden test is automatically entered after burden measurement. If "I-sn" is defined, the burden is updated immediately after the burden test is finished. If "I-sn" is not defined (entry "?"), the burden is updated after the resistance test.

These parameters can also be changed after the test or in a loaded test report in order to check the CT behavior at different burden values.

f Rated frequency of the CT.Possible values: Integer value between 16 and 400 Hz (keyboard) or soft keys 1 6 . 7 H Z, 5 0 H Z, 6 0 H Z or 4 0 0 H Z.Default value: Frequency defined in the default test settings.

Rct Specified winding resistance.

Possible values: 0 to 300 ohms (keyboard) or soft key ? .Default value: "?".


α 5Irated-------------⎝ ⎠⎛ ⎞ 2

=

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62

Specific parameters and settings displayed for IEC 60044-1, class PThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-1, class P for protection CTs is selected.

Table 5-6:Parameters displayed in the CT-Object card for IEC 60044-1 class P

Class mult. factor

Class multiplying factor.

This factor increases the assessment level for the ratio test. E.g. a class multiplier of 0.5 means that the maximum accepted tolerance for the ratio error is only half the standard tolerance (all ratio tolerance values are multiplied with the entered factor).

Possible values: 0.25 to 1.00 (keyboard) or soft key 1 . 0 .Default value: 1.0.

Delta com-pensation

Correction factor for the ratio measurement. This factor enables the ratio measurement for CTs that are installed inside a delta winding transformer.Possible values: Soft keys R A T I O 1 , R A T I O 2 / 3 or R A T I O 1 / 3 .Default value: "Ratio 1".Choose "Ratio 1", if no correction is required.Choose "Ratio 2/3", if input PRIM is connected to the two terminals of that transformer winding, the CT is in series.Choose "Ratio 1/3" if input PRIM is connected to the terminals of a transformer winding, the CT is not in series with.


Parameter DescriptionALF Accuracy limiting factor acc. to IEC 60044-1.

Possible values: Integer value from 1 to 300 (keyboard) or soft keys ? , 5 , 1 0 , 1 5 , 2 0 or 3 0 .Default value: "?".If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the accuracy limiting factor. See the flow chart in section 10.18 on page 198.


63

Specific parameters and settings displayed for IEC 60044-1, class PRThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-1, class PR for protection CTs is selected.

Table 5-7:Parameters displayed in the CT-Object card for IEC 60044-1 class PR

Specific parameters and settings displayed for IEC 60044-1, class PXThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-1, class PX for protection CTs is selected.

Table 5-8:Parameters displayed in the CT-Object card for IEC 60044-1 class PX

Parameter DescriptionALF Accuracy limiting factor acc. to IEC 60044-1.

Possible values: Integer value from 1 to 300 (keyboard) or soft keys ? , 5 , 1 0 , 1 5 , 2 0 or 3 0 .Default value: "?".If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the accuracy limiting factor. See the flow chart in section 10.18 on page 198.

Ts Specified secondary time constant.

Possible values: 0.000 to 100.0s (keyboard) or soft key ? .Default value: 100s.

Parameter DescriptionKx Dimensioning factor according to IEC 60044-1 class PX.

Possible values: 1 to 300 (keyboard) or soft key ? .Default value: "?".

Ek Accuracy limiting voltage according to IEC 60044-1 class PX.

Possible values: 0 to 20000 (keyboard) or soft key ? .Default value: "?".

Ie Accuracy limiting current according to IEC 60044-1 class PX.

Possible values: 0.03mA to 30A (keyboard) or soft key ? .Default value: "?".

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64

Specific parameters and settings displayed for IEC 60044-1, measurement CTsThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-1 is selected with the type "Measurement CT".

Table 5-9:Parameters displayed in the CT-Object card for IEC 60044-1, measurement CTs

E1 User-defined e.m.f. to verify the excitation current at this specific e.m.f.

Possible values: 0.1 to 20000V (keyboard) or soft key ? .Default value: "?".If the question mark is entered, half the voltage entered or measured for Ek is used.

Ie1 Maximum allowed excitation current at E1.

Possible values: 0.03mA to 30000mA (keyboard) or soft key ? .Default value: "?".If the question mark is entered, the CT Analyzer uses the excitation current measured at the voltage value defined at E1. In this case, the assessment for this parameter is OK.


Parameter DescriptionFS Instrument security factor acc. to IEC 60044-1.

Possible values: Integer value from 1 to 30 (keyboard) or soft keys ? , F S 1 , F S 1 . 5 , F S 2 , F S 5 , F S 1 0 , F S 2 0 or F S 3 0 .Default value: "?".If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the instrument security factor. See the flow chart in section 10.18 on page 198.

ext Extended current rating.

Possible values: 100 to 400% (keyboard) or soft keys 1 2 0 % , 1 5 0 % , 2 0 0 % , 3 0 0 % , 4 0 0 % .Default value: 120%.


65

Specific parameters and settings displayed for IEC 60044-6, class TPSThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-6, class TPS is selected.

Table 5-10:Parameters displayed in the CT-Object card for IEC 60044-6 class TPS

Parameter DescriptionKssc Rated symmetrical short-circuit current factor.

Possible values: 1 to 300A (keyboard) or soft keys ? , 3 , 5 , 7 . 5 , 1 0 , 1 2 . 5 , 1 5 , 1 7 . 5 , 2 0 , 2 5 , 3 0 , 4 0 or 5 0 .

Default value: "?".

If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the symmterical short-circuit current factor. See the flow chart in section 10.18 on page 198.

Tp Primary time constant.

Possible values: 0.000 to 5.000s (keyboard) or soft keys 2 0 M S, 4 0 M S, 6 0 M S, 8 0 M S, 1 0 0 M S or 1 2 0 M S.

Tp depends on K as follows:

K Dimensioning factor.

Possible values: 1 to 1572 (keyboard).

K depends on Tp as described above for parameter Tp.

V-al Rated equivalent excitation limiting secondary voltage.

Possible values: 0 to 9999V (keyboard) or soft key ? .

Default value: "?".I-al Accuracy limiting secondary excitation current.

Possible values: 0.03mA to 30A (keyboard) or soft key ? .

Default value: "?".E1 User-defined e.m.f. to verify the excitation current at this specific

e.m.f.

Possible values: 0.1 to 20000V (keyboard) or soft key ? .If the question mark is entered, half the voltage entered or measured for Ek is used.

TpK 1–

ω-------------=

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66

Specific parameters and settings displayed for IEC 60044-6, class TPXThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-6, class TPX is selected.

Table 5-11:Parameters displayed in the CT-Object card for IEC 60044-6 class TPX

Ie1 Maximum allowed excitation current at E1 (user-defined e.m.f.).

Possible values: 0.03mA to 30A (keyboard) or soft key ? .If the question mark is entered, the CT Analyzer uses the excitation current measured at the voltage value defined at E1. In this case, the assessment for this parameter is OK.



Possible values: 1 to 300A (keyboard) or soft keys ? , 3 , 5 , 7 . 5 , 1 0 , 1 2 . 5 , 1 5 , 1 7 . 5 , 2 0 , 2 5 , 3 0 , 4 0 or 5 0 .

Default value: "?".Tp Primary time constant.


Default value: 0.02s.Ktd Rated transient dimensioning factor.

Possible values: 1.0 to 2043 (keyboard) or soft key ? .

Default value: "?".Duty Specified duty cycle.

Using the soft keys, two different energizing cycles can be selected:

Default value: "C-O".


67

t1 Duration of first current flow. The specified accuracy limit must not be reached within time "t-al1".

Possible values: 0.000 to 5.000s (keyboard) or soft key 1 0 0 M S.

Default value: 0.1s.t2 Duration of second current flow. The specified accuracy limit

must not be reached within time "t-al2".

This parameter is only displayed if "Duty" is C-O-C-O.


Default value: 0.1s.t-al1 Permissible time to accuracy limit for first energizing period of

the duty cycle.

Possible values: 0.000 to 5.000s and max. t1 (keyboard) or soft key 4 0 M S.

Default value: 0.04s.t-al2 Permissible time to accuracy limit for second energizing period

of the duty cycle.



Default value: 0.04s.tfr Dead time between first opening and reclosure.



Default value: 0.3s.


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68

Specific parameters and settings displayed for IEC 60044-6, class TPYThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-6, class TPY is selected.

Table 5-12:Parameters displayed in the CT-Object card for IEC 60044-6 class TPY


Possible values: 1 to 300A (keyboard) or soft keys displayed when the field is selected.





Default value: "?".Ts Specified secondary time constant.

Possible values: 0.000 to 100.0s (keyboard) or soft key ? .

Default value: "?".Duty Specified duty cycle.

Using the soft keys, two different energizing cycles can be selected:

t1 Duration of first current flow. The specified accuracy limit must not be reached within time "t-al1".




69

t2 Duration of second current flow. The specified accuracy limit must not be reached within time "t-al2".



Default value: 0.1s.t-al1 Permissible time to accuracy limit for first energizing period of

the duty cycle.


Default value: 0.04s.t-al2 Permissible time to accuracy limit for second energizing period

of the duty cycle.



Default value: 0.04s.tfr Dead time between first opening and reclosure.





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70

Specific parameters and settings displayed for IEC 60044-6, class TPZThe following parameters are only displayed in the CT-Object card, if the standard IEC 60044-6, class TPZ is selected.

Table 5-13:Parameters displayed in the CT-Object card for IEC 60044-6 class TPZ

Specific parameters and settings displayed for IEEE C57.13 (ANSI 30, ANSI 45), protection CTsThe following parameters are only displayed in the CT-Object card, if the standard ANSI 30 or ANSI 45 is selected with the type "Protection CT".

Table 5-14:Parameters displayed in the CT-Object card for ANSI 30 or ANSI 45, protection CTs


Possible values: 1 to 300A (keyboard) or soft keys displayed when the field is selected.





Default value: "?".Ts Specified secondary time constant.

Possible values: 0.000 to 100.0s (keyboard) or soft key ? .

Default value: "?".

Parameter DescriptionVb Rated secondary terminal voltage.

Possible values: Integer values from 10 to 1200A (keyboard) or soft keys ? , 1 0 V, 2 0 V, 5 0 V, 1 0 0 V, 2 0 0 V, 4 0 0 V or 8 0 0 V.

Default value: "?".

If the question mark is entered and a new test is started, the CT Analyzer automatically tries to guess the secondary terminal voltage. See the flow chart on page 200.


71

Specific parameters and settings displayed for IEEE C57.13 (ANSI 30, ANSI 45), measurement CTsThe following parameters are only displayed in the CT-Object card, if the standard ANSI 30 or ANSI 45 is selected with the type "Measurement CT".

Table 5-15:Parameters displayed in the CT-Object card for ANSI 30 or ANSI 45, measurement CTs

Parameter DescriptionRF Continuous current rating factor.

Possible values: Value from 1.0 to 4.0A (keyboard) or soft keys R F 1 . 5 , R F 2 , R F 3 or R F 4 .

Default value: 2.

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72

5.5 Burden CardThe Burden card is only available, if it is enabled in the Select Cards page (Default Test Card Selection or S E L E C T C A R D S soft key in the CT-Object card).Using the Burden card, a current transformer’s secondary burden impedance can be measured with the selected secondary current (I-sn) at nominal frequency. If a current other than I-sn should be used to test the burden, the desired test current can be entered in the parameter field "I-test".No soft keys are available in the Burden card.

Figure 5-21:Burden card with "remote" icon (left) and with overload indication (right)

If the CT Analyzer cannot reach the desired test current I-test, an overload message is displayed in the right-hand corner of the status line (see figure 5-21).

5.5.1 Test SettingsThe following settings can be done in the Burden card.

Table 5-16:Test settings for the burden test

Parameter DescriptionI-test Test current used to measure the external burden.

After clearing the test results or when starting a new CT test, the test current is chosen as follows:

It is possible to overwrite the default test current using the keyboard (0.1 to 5A).

Value entered for I-sn

in CT-Object card

Value entered for I-test

in Burden card

Test current used for burden test

"?" none 1Ae.g. "?" e.g. 5A 5A (value of I-test)e.g. 5A none 5A (value of I-sn)e.g. 5A e.g. 1A 1A (value of I-test)


73

5.5.2 Test ResultsThe lower part of the Burden card shows the results of the burden test after the test is finished.

Table 5-17:Burden test results

5.5.3 Connecting the Burden and Running the Test1. For the burden test, connect the burden to the CT Analyzer as shown in

figure 5-22. You can display the connection diagram by pressing the H E L P key on the keyboard while the Burden card is open.

Figure 5-22:CT Analyzer help page for burden wiring

2. In the Burden card, use the default test current or enter the desired test current to parameter "I-test" and start the burden test by pressing the I / 0 key.

3. A message appears prior to the test notifying you that you should check the wiring before running the test (figure 5-23).

Parameter DescriptionI-meas Current measured during the test.V-meas Voltage measured at the load during the test.Burden / Cos ϕ

Calculated as follows:

If the rated secondary current is not known, the result field will only show "n/a" as long as I-sn is not defined.

Z Calculated as follows:

22 RXRCosL +

=ϕBurden Isn2 Z×=

ZUrmsIrms------------=

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74

Figure 5-23:Message displayed prior to burden test

Check the wiring (refer to figure 5-22) and then press the S T A R T T E S T soft key to start the burden test. Or press C A N C E L T E S T to abort the burden test.

If you do not want to execute the burden test, press S K I P T E S T . This will skip the burden test and immediately start the CT test without a previous burden test. This allows you to repeat the CT test without repeating the burden test.


75

5.6 Resistance CardThe Resistance card is only available, if it is enabled in the Select Cards page (Default Test Card Selection or S E L E C T C A R D S soft key in the CT-Object card).For testing a CT, the Resistance card is always required since the CT winding resistance is needed for particular calculations in the excitation and ratio test.The test is performed completely automatically. For the test, a DC signal is applied to the CT until the transformer saturates. When saturation of the CT is reached, the measurement is done. If only a winding resistance test is selected, a demagnetizing cycle is performed after the test to guarantee complete demagnetization of the CT.

Figure 5-24:Resistance card

5.6.1 Test SettingsThe following settings are required to perform the resistance test.

Table 5-18:Test settings for the resistance test

Parameter DescriptionI-test Test current used to measure the winding resistance. The value

of the test current cannot be changed. Its maximum value is 1 A.

If Isn is between 0.1 and 1 A, I-test is automatically set to Isn.If Isn is lower than 0.1 A, I-test is automatically set to 0.1 A.

T-meas Winding temperature of the CT when the measurement is performed.

Possible values: -40 to 150°C or -40 to 302°F (keyboard).

Default value: Ambient Temperature defined in the Settings (main menu).

If this temperature is not set correctly, the reference resistance value (R-ref) at reference temperature will not be calculated correctly.

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76

5.6.2 Test ResultsThe following parameters show the results of the resistance test after the test is finished.

Table 5-19:Resistance test results

T-ref Reference temperature, i.e temperature the CT is specified for.

Possible values: -40 to 150°C or -40 to 302°F (keyboard).

Default value: 75°C.

This parameter can also be changed after the test in order to recalculate the test results accordingly.

The winding resistance at reference temperature is calculated from the winding resistance measured at ambient temperature (T-meas) and the specified reference temperature.


Parameter DescriptionI-DC Measurement current.V-DC Measurement voltage.R-meas Measured resistance at ambient temperature, calculated as

follows: R-meas = V-DC / I-DC

R-ref Reference resistance (temperature-compensated resistance, compensated to T-ref). Calculated as follows:

RrefVDCIDC----------

234.5 Tref+234.5 Tmeas+----------------------------------×=


77

5.7 Excitation CardThe Excitation card is only available, if it is enabled in the Select Cards page (Default Test Card Selection or S E L E C T C A R D S soft key in the CT-Object card).

The excitation test is used to trace the excitation curve of the current transformer and to determine many CT-specific parameters (see test results below). The test is done completely automatically up to a current of 15Apeak.

CTs with closed cores can be tested up to a knee point voltage of 15kV. For CTs with gapped cores the maximum test voltage and current is limited depending on the maximum output power of the device. Typical maximum current and voltage values for a TPZ core are 9Arms at 1200Vrms.

The settings for the excitation test are specified in the CT-Object card. For a better understanding of the test results, the most important settings from the CT-Object card are shown in the upper part of the Excitation card.

The test results displayed in the lower part of the Excitation card depend on the standard selected in the CT-Object card. Using the soft keys, the user can choose between different sets of results. If the soft key R E S U L T S W I T H N O M. B U R D E N is pressed, the page shows the results related to the nominal burden (parameter "VA" in CT-Object card). If the soft key R E S U L T S W I T H O P. B U R D E N is pressed, the page shows the results related to the operating burden (parameter "Burden" in CT-Object card).

Pressing the soft key E X C I T . G R A P H opens a page with the excitation graph (see page 85).

Pressing the soft key K - V A L U E E R R O R G R A P H opens a page with a graph showing the maximum possible primary current (K * Ipn) that can flow over a specific burden without exceeding the accuracy limit (5% or 10%).

Figure 5-25:Excitation card with values related to nominal burden

If the CT Analyzer displays an overload in the Excitation card, either the desired knee point could not be reached or not all necessary measurement points could be taken (e.g. in the knee point area, not enough points for a proper calculation of the knee point could be measured).

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78


5.7.2 SettingsThe upper part of the Excitation card shows the test settings adjusted in the CT-Object card.

5.7.3 Test ResultsThe test results are displayed in the lower part of the Excitation card. The display of test results depends

• on the standard defined in the CT-Object card, the class and the type of CT (measurement or protection CT) and

• the burden selected with the soft key (R E S U L T S W I T H N O M. B U R D E N or R E S U L T S W I T H O P. B U R D E N).

The following tables provide an overview of which test results (parameters) are displayed for which standard.

Opens the excitation graph page (refer to section 5.7.4 on page 85).

Displays the results related to the nominal burden of the CT.

Displays the results related to the operating burden.

Opens the K-value error graph page (refer to section 5.7.5 on page 88).

This graph is part of Chinese standards and shows the maximum possible primary current (K * Ipn) that can flow over a specific burden without exceeding the accuracy limit.


79

Table 5-20:Excitation card, test results displayed for IEC 60044-1

Note: Depending on the selected burden, the Excitation card shows the results either calculated with the nominal burden (R E S U L T S W I T H N O M. B U R D E N) or calculated with the operating burden (R E S U L T S W I T H O P. B U R D E N).

The displayed pages are identical to a large extend, except the field label for the burden parameter ("VA" in case of nominal burden and "Burden" in case of operating burden) and the result values.

Para-meter

Description Results displayed forIEC 60044-1

meas. CT prot. CTV-kn

V-kn1

Knee point voltage (acc. to standard) of the uppermost knee point found (definition of knee point see section 10.15 on page 192).

x x

I-kn

I-kn1

Knee point current (acc. to standard) of the uppermost knee point found. x x

V-kn2 Knee point voltage (acc. to standard) of the lowest knee point found (definition of knee point see section 10.15 on page 192).

x x

I-kn2 Knee point current (acc. to standard) of the lowest knee point found. x x

ALF Accuracy limiting factor according to IEC 60044-1 direct measurement method, calculated for nominal and operating burden (calculation see section 10.6.1 on page 184).

If the CT Analyzer is not able to measure up to the actual accuracy limiting factor, the prefix ">" is displayed to indicate that the ALF is larger than the displayed value.

class P &class PR

only

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80

ALFi Accuracy limiting factor according to IEC 60044-1 indirect measurement method, calculated for nominal and operating burden (calculation see section 10.6.2 on page 186).

If the CT Analyzer is not able to measure up to the actual accuracy limiting factor, the prefix ">" is displayed to indicate that the ALFi is larger than the displayed value.

class P & class PR

only

Kx Dimensioning factor (acc. to IEC 60044-1 class PX) at accuracy limit with the selected load.

class PX only

FS Instrument security factor according to IEC 60044-1 direct measurement method, calculated for nominal and operating burden (calculation see section 10.5.1 on page 179).

If the CT Analyzer is not able to measure up to the actual instrument security current, the prefix ">" is displayed to indicate that FS is larger than the displayed value.

x

FSi Instrument security factor according to IEC 60044-1 indirect measurement method, calculated for nominal and operating burden (calculation see section 10.5.2 on page 181).

If the CT Analyzer is not able to measure up to the actual instrument security current, the prefix ">" is displayed to indicate that FSi is larger than the displayed value.

x

Ls Saturated inductance (calculation see section 10.13 on page 191). x x

Lm Non-saturated inductance (calculation see section 10.14 on page 192). x x

Para-meter


meas. CT prot. CT


81

Table 5-21:Excitation card, test results displayed for IEC 60044-6

Ts Secondary time constant (calculation method see section 10.10 on page 188).

x x

Kr Remanence factor (calculation see section 10.12 on page 190). x x

Ek Accuracy limiting voltage according to IEC 60044-1 for class PX (that point on the excitation graph where an increase of the e.m.f. rms voltage (core flux) by 10 % causes an increase of the rms current by 50%).

class PX only

Ie Accuracy limiting current according to IEC 60044-1 class PX (at Ek).

class PX only

E1 User-defined e.m.f. to verify the excitation current at this e.m.f.

class PX only

Ie1 Max. allowed excitation current at E1. class PX only

Para-meter


meas. CT prot. CT



Para-meter

Description Results displayed forIEC 60044-6, class

TPS TPX / TPY

TPZ

V-kn Knee point voltage according to standard (definition of knee point see section 10.15 on page 192).

x x x

I-kn Knee point current according to standard. x x x

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82

Kssc Rated symmetrical short-circuit current factor at accuracy limit with the selected load (calculation see section 10.8 on page 187).

If the CT Analyzer is not able to measure up to the actual short circuit current factor, the prefix ">" is displayed to indicate that the Kssc is larger than the displayed value.

x x x

Ktd Theoretical transient dimensioning factor (calculation see section 10.17 on page 196).

x x

Ls Saturated inductance (calculation see section 10.13 on page 191). x x x

Lm Non-saturated inductance (calculation see section 10.14 on page 192). x x x

Ts Secondary time constant (calculation see section 10.10 on page 188). x x x

Kr Remanence factor (calculation see section 10.12 on page 190). x x x

V-al Accuracy limiting voltage according to IEC 60044-6 for class TPS (that point on the excitation graph where an increase of the emf rms voltage (core flux) by 10 % causes an increase of the peak current by 100 %).

x

I-al Accuracy limiting current according to IEC 60044-6 class TPS (at V-al). x

E1 User-defined e.m.f. to verify the excitation current at this e.m.f. x

Ie1 Max. allowed excitation current at E1. x

Para-meter


TPS TPX / TPY

TPZ


83

Table 5-22:Excitation card, test results displayed for ANSI (IEEE C57.13)

E-max Maximum emf voltage.

This parameter allows the determination of the working point on the excitation curve that would be reached with the entered settings.

x

ε^ Peak instantaneous error at voltage Emax (calculation see section 10.7 on page 187).

x

Para-meter


TPS TPX / TPY

TPZ

Emax Kdt_meas Kssc Isn RCT Rb+( )2 Xb2+⋅( )⋅ ⋅=



Para-meter

Description Results displayed for ANSI (IEEE C57.13)

meas. CT prot. CTV-kn Knee point voltage according to standard

(definition of knee point see section 10.15 on page 192).

x x

I-kn Knee point current according to standard. x x

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FS Instrument security factor (direct measurement method), calculated for nominal and operating burden (calculation see section 10.5.1 on page 179).

If the CT Analyzer is not able to measure up to the actual instrument security current, the prefix ">" is displayed to indicate that FS is larger than the displayed value.

x

FSi Instrument security factor (indirect measurement method), calculated for nominal and operating burden (calculation see section 10.5.2 on page 181).

If the CT Analyzer is not able to measure up to the actual instrument security current, the prefix ">" is displayed to indicate that FSi is larger than the displayed value.

x

Vb Rated secondary terminal voltage. xLs Saturated inductance (calculation see

section 10.13 on page 191). x x

Lm Non-saturated inductance (calculation see section 10.14 on page 192). x x

Ts Secondary time constant (calculation method see section 10.10 on page 188). x x


Para-meter

Description Results displayed for ANSI (IEEE C57.13)

meas. CT prot. CT


85

5.7.4 Excitation GraphThe excitation graph page shows the graph calculated from the test results. To display the excitation graph, press the E X I T . G R A P H soft key in the Excitation card. The graph shows the rms terminal/core voltage over the rms/peak current depending on the selected standard.

On the bottom right of the diagram the voltage, current and inductance values for the selected point in the graph are displayed. The currently selected point in the graph is marked by a horizontal and a vertical dashed line.

In this page it is possible to load the excitation graph of an already saved test from the Compact Flash card in order to compare this graph with the one of the current test.

Figure 5-26:Excitation graph

Table 5-23:Definition of the axes in the excitation graph for different standards

Available soft keys

Definition of axes for different standardsStandard Vertical axis Horizontal axisIEC 60044-1 rms terminal voltage rms excitation currentIEC 60044-6 rms emf voltage1

1. Calculation of the rms emf voltage see section 10.4 on page 178.

peak excitation current

IEEE C57.13 (ANSI) rms emf voltage1 rms excitation current

Moves the cursor upwards on the excitation graph.

Moves the cursor downwards on the excitation graph.

Switches off the display of values on the bottom right of the diagram. If you have switched off the values, this soft key changes to T E X T O N to switch the values display on again.

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Closes the excitation graph and brings you back to the Excitation card.

Moves the cursor to the knee point on the graph according to the selected standard.

If two or more knee points could be found on the graph, this soft key is alternately labelled K N E E P O I N T 1 or K N E E P O I N T 2 , depending on which knee point the cursor is actually positioned to. After opening the excitation graph, the cursor shows the uppermost knee point (knee point 1) and the soft key is labelled K N E E P O I N T 2 :

– Pressing K N E E P O I N T 2 moves the cursor to the lowest knee point on the graph. The labelling changes to K N E E P O I N T 1 .

– Pressing K N E E P O I N T 1 moves the cursor to the uppermost knee point on the graph. The labelling changes to K N E E P O I N T 2 .

Moves the cursor to the knee point on the reference graph. This soft key is only available if a reference graph is loaded.

If the reference graph loaded has two or more knee points, this soft key is alternately labelled R E F. K N E E P O I N T 1 or R E F . K N E E P O I N T 2 , depending on which knee point the cursor is actually positioned to. After loading the reference graph, the cursor shows the uppermost knee point (knee point 1) and the soft key is labelled R E F . K N E E P O I N T 2 :

– Pressing R E F . K N E E P O I N T 2 moves the cursor to the lowest knee point on the reference graph. The labelling changes to R E F . K N E E P O I N T 1 .

– Pressing R E F . K N E E P O I N T 1 moves the cursor to the uppermost knee point on the reference graph. The labelling changes to R E F . K N E E P O I N T 2 .

Opens the file system card to select a previous test in order to load the excitation curve of this test as a reference curve and compare it with the current one.

The reference curve is displayed as a dotted line in addition to the excitation curve of the actual test. If a reference curve is loaded, the values "V-ref", "I-ref" and "L-ref" are displayed in addition to the measured values.


87

Viewing the measured values for different points on the graphBy default, the knee point values are displayed after opening the excitation graph page. However, you can also view the corresponding voltage, current and inductance values for any point on the graph. To select a specific point on the graph,

• either use the soft keys (C U R S O R U P, C U R S O R D O W N, K N E E P O I N T )

• or enter a specific voltage or current value using the keyboard:

– Select the desired edit field using the cursor keys on the keyboard.

– Enter the desired voltage or current value using the keyboard.

– Press the E N T E R key to apply the entered value and read the corresponding values in the respective fields (e.g. "V-meas" and "L-meas" if you have entered a current "I-meas").

Figure 5-27:Entering a current value to display its corresponding voltage and inductance values on the excitation graph

Switches off the reference curve from the display. If you have switched off the reference curve, the soft key changes to R E F . O N to switch the reference curve on again.

This soft key is only available if a reference curve has been loaded.

By pressing one of these soft keys you can display the measured excitation graph and knee point as defined in the respective standard.

Note: The test report only contains the graph for the standard selected in the CT-Object card.

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5.7.5 K-Value Error GraphTo display the K-Value error graph, press the soft key K - V A L U E E R R O R G R A P H in the Excitation card.

According to the "China Electric Regulations for protection CTs", it is necessary to draw an error curve that shows the maximum possible primary current (K * Ipn) that can flow over a specific burden without exceeding the accuracy limit (or, in other words, that shows which burden value can be connected at which primary current (K * Ipn) without exceeding the accuracy limit).

Depending on the class (5P or 10P), the accuracy limit is 5% or 10%:

All standards are supported, except IEC 60044-6 class TPZ.

Figure 5-28:K-value error graph

Available soft keys

Note: The function "K-Value Error Graph" can be switched on or off in the device settings (M A I N M E N U, entry "Settings" -> S E T T I N G M E N U, entry "K-Value Error Graph"). If switched off, the K-value error graph is not included in the test report.

IextIsn ALFi⋅------------------------ 100⋅ 10 or 5=

Moves the cursor upwards on the error graph.

Moves the cursor downwards on the error graph.

Switches off the display of values on the top right of the diagram. If you have switched off the values, this soft key changes to T E X T O N to switch the values display on again.


89

Viewing the measured values for different points on the graphBy default, the cursor is positioned to the nominal burden values after opening this page.

To select a specific point on the graph:

– Select the desired edit field "K-Value" or "Burden" using the C U R S O R U P/ D O W N keys on the keyboard and enter the desired value using the keyboard.

– Press the E N T E R key to apply the entered value and read the corresponding value in the respective field.

Closes the K-value error graph and brings you back to the Excitation card.

Moves the cursor to that point on the error graph that corresponds to the nominal burden value defined in the "VA" field of the CT-Object card (value entered by the user or determined by the guesser function of the CT Analyzer).

Moves the cursor to that point on the error graph that corresponds to the operating burden value defined in the "Burden" field of the CT-Object card (value entered by the user or determined by the guesser function of the CT Analyzer).

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5.8 Ratio CardThe Ratio card is only available if it is enabled in the Select Cards page (Default Test Settings or S E L E C T C A R D S soft key in the CT-Object card).

The ratio test measures the current ratio of the CT considering the operating burden (parameter "Burden" in CT-Object card) or the nominal burden (parameter "VA" in CT-Object card).

The results of the ratio test can be found in 3 pages:

• The Ratio card shows the polarity, the ratio error and phase displacement for the primary current and the operating burden defined in the CT-Object card (refer to figure 5-29).

• The ratio table shows the current ratio error for different currents (200% down to 1% of the rated current) at 100%, 50% and 25% of the nominal burden (as defined in the "VA" field of the CT-Object card), and at 1VA.

• The phase table shows the phase displacement for different currents at 100%, 50% and 25% of the nominal burden (as defined in the "VA" field of the CT-Object card), and at 1VA.

For a better understanding of the test results, the most important settings from the CT-Object card are shown once again in the upper part of the Ratio card.

Figure 5-29:Ratio card


Note: Although the test is not performed with the real current, the test results reflect the current ratio and not the voltage ratio.

Displays the ratio table (refer to section 5.8.4 on page 92).

Displays the phase table (refer to section 5.8.4 on page 92).


91

5.8.2 SettingsThe following settings can be done in the Ratio test card.

Table 5-24:Settings in the Ratio card

5.8.3 Test ResultsThe following test results are displayed in the lower part of the Ratio card. In addition to the results displayed in the Ratio card you can view the ratio and phase table pages described in section 5.8.4 on page 92.

Table 5-25:Test results in the Ratio card

Parameter DescriptionI-p Primary current for calculation of the ratio error and phase

displacement with the burden (operating burden) defined in the CT-Object card.

After the test is finished, it is possible to change the value for the primary current. The ratio error and/or the phase error are then recalculated and displayed again. When storing the test results, the currently displayed measurement results are stored.

Changing this value only influences the results displayed in the Ratio card (operating burden-related values). It does not affect the values displayed in the separate pages for the ratio and phase tables (values related to nominal burden).

Default value: I-pn

Parameter DescriptionRatio Current ratio error (in %) at the specified primary current ("I-p")

and burden.Pol. OK: Polarity OK, phase angle is in the range of 0° ± 45°.

Failed: Wrong polarity of the CT or wrong polarity of the measurement leads.

εC Composite error in % at the specified primary current ("I-p") and operating burden (calculation see sections 10.5 on page 179 and 10.6 on page 184).

This parameter is only displayed, if the standard IEC 60044-1 or the ANSI standard is selected in the CT-Object card.

Phase Phase displacement (in minutes) at the specified primary current ("I-p") and burden.

N Winding turns ratio.

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5.8.4 Ratio Table and Phase TableTo display the ratio table or the phase table, press the R A T I O T A B L E or P H A S E T A B L E soft key in the Ratio card. These tables show the ratio error and the phase displacement• for different current values (between 1% and 200% of the rated current). If

the ANSI standard is selected, the value at I-pn*RF is shown instead of the 200% value.

• at 100%, 50% and 25% of the nominal burden (defined in the "VA" field of the CT-Object card) and at 1VA, if the standard IEC 60044-1 or IEC 60044-6 is selected.

• at the standard burden values, if IEEE C57.13 is selected (refer to subsection "Calculation of burden values for "Ratio Table" and "Phase Table" below).

The ratio table and the phase table contain all measurement points defined in the supported standards (refer to section 10.4 on page 178).Use the C U R S O R L E F T / R I G H T keys on the keyboard to scroll through the table columns (1% of rated current to 200% of rated current).

Figure 5-30:Ratio card, ratio table page

Figure 5-31:Ratio card, phase table page

εt Turns ratio error acc. to IEC 60044-6 class TPS or IEC 60044-1 class PX (calculation see section 10.2 on page 177).


Note: Values without the prefix "!" have guaranteed accuracy. The accuracy of values marked with a "!" in the tables is reduced by factor 2.


93

Calculation of burden values for "Ratio Table" and "Phase Table", if standard IEEE C57.13 (ANSI 30 or ANSI 45) is selectedFor IEEE C57.13 measurement (M) cores:

Internally, the device has the following sorted table with burden values as defined in the standard:

• 45.0VA (B 1.8)

• 22.5VA (B 0.9)

• 12.5VA (B 0.5)

• 5.0VA (B 0.2)

• 2.5VA (B 0.1)

The value in the parameter field VA on the CT-Object card is now added to this sorted table at the corresponding position.

For example, if the value for VA on the CT-Object card is 25VA, the internal burden table will look as follows:

• 45.0 VA

• 25.0 VA (defined on CT-Object card)

• 22.5 VA

• 12.5 VA

• 5.0 VA

• 2.5 VA

Only four values are used for the table on the Ratio card: the value defined on the CT-Object card and the lowest three values of the standard table "around" the value on the CT-Object card.

In this example (value defined is 25VA), the values 45.0VA and 2.5VA are ignored. The following values are used:

• 25.0 VA (defined on CT-Object card)

• 22.5 VA

• 12.5 VA

• 5.0 VA

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If the VA parameter value entered on the CT-Object card is 15, the following values are used (values 45.0VA and 22.5VA are ignored):

• 15.0 VA• 12.5 VA• 5.0 VA• 2.5 VA

If the VA parameter value entered on the CT-Object card is 60, the following values are used (values 5.0VA and 2.5VA are ignored):

• 60.0 VA• 45.0 VA• 22.5 VA• 12.5 VA

If the VA parameter value entered on the CT-Object card is B 0.5 (corresponds to 12.5 VA), the following values are used (value 45.0VA is ignored):

• 22.5 VA• 12.5 VA• 5.0 VA• 2.5 VA

For IEEE C57.13 protection (P) cores:

Internally, the device has the following sorted table with burden values as defined in the standard:

• 200.0VA (B 8)• 100.0VA (B 4)• 50.0VA (B 2)• 25.0VA (B 1)

The value in the parameter field VA on the CT-Object card is now added to this sorted table at the corresponding position.

For example, if the value for VA on the CT-Object card is 150VA, the internal burden table will look as follows:

• 200.0 VA• 150.0 VA (defined on CT-Object card)• 100.0 VA• 50.0 VA• 25.0 VA


95

Only four values are used for the table on the Ratio card: the value defined on the CT-Object card and the lowest three values of the standard table "around" the value on the CT-Object card. If the value defined on the CT-Object card is a standard value, the four values of the standard table are used.

In this example (value defined is 150VA), the value 200.0VA is ignored. The following values are used:

• 150.0 VA

• 100.0 VA

• 50.0 VA

• 25.0 VA

If the VA parameter value entered on the CT-Object card is 300.0VA, the following values are used (value 25.0VA is ignored):

• 300.0 VA

• 200.0 VA

• 100.0 VA

• 50.0 VA

If the VA parameter value entered on the CT-Object card is 200.0VA, the following values are used (no value ignored since 200.0VA is a standard value):

• 200.0 VA

• 100.0 VA

• 50.0 VA

• 25.0 VA

If the VA parameter value entered on the CT-Object card is 10.0VA, the following values are used (value 200.0VA is ignored):

• 100.0 VA

• 50.0 VA

• 25.0 VA

• 10.0 VA

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5.9 Assessment CardThe Assessment card is only available if it is enabled in the Select Cards page (Default Test Card Selection or S E L E C T C A R D S soft key in the CT-Object card).

Depending on the standard and the type of CT (protection or measurement CT), the according parameters are listed.

The column for automatic assessment ("Auto") is automatically filled after the test is finished. The following assessments are possible:

• "OK": The results measured for this parameter comply with the requirements defined by the selected standard and the parameters in the CT-Object card.

• "Failed": The results do not comply with the requirements.

• "n/a": No assessment possible due to one of the following reasons:

• Comparison with input parameter is not possible.

• Assessment does not make sense due to incorrect polarity or invalid measurement value.

It is also possible to perform a manual assessment for the individual parameters. To do this, select the parameter to be assessed using the cursor keys on the keyboard and apply your assessment using the soft keys O K , F A I L E D or ? .

Figure 5-32:Assessment card (example)

Note: Automatic assessment is only performed for the CT behavior at nominal burden (parameter "VA" on the CT-Object card).

For the CT behavior at operating burden (parameter "Burden" on the CT-Object card), no automatic assessment is performed.


97

5.9.1 Assessed ParametersParameters assessed for standard IEC 60044-1

Table 5-26:Parameters assessed for IEC 60044-1

Parame-ter

Description Parameter assessed for IEC 60044-1,

prot

. CT,

clas

s P

prot

. CT,

clas

s PR

prot

. CT,

clas

s PX

mea

s. C

T

Class Accuracy class according to standard. x x x xε Current ratio error. x x xΔϕ Phase deviation. x x xεt Turns ratio error (included in class). xεc Composite error. x xFS Instrument security factor (direct

measurement method, calculation see section 10.5.1 on page 179).

x

FSi Instrument security factor (indirect measurement method, calculation see section 10.5.2 on page 181).

x

ALF Accuracy limiting factor (direct measurement method, calculation see section 10.6.1 on page 184).

x x

ALFi Accuracy limiting factor (indirect measurement method, calculation see section 10.6.2 on page 186).

x x

Ek Rated knee point emf. xIe Accuracy limiting secondary excitation

current. x

Ie1 Max. allowed secondary excitation current at E1. x

Kx Dimensioning factor (according to IEC 60044-1 class PX). x

Rct Secondary winding resistance. x x x xTs Secondary time constant (calculation

method see section 10.10 on page 188). x x x x

Kr Remanence factor (calculation see section 10.12 on page 190). x x x x

Burden Manual assessment of the user for the burden test (no automatic assessment performed).

x x x x

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Parameters assessed for standard IEC 60044-6Table 5-27:Parameters assessed for IEC 60044-6

Parame-ter

Description Parameter assessed for IEC 60044-6,

class

TPS

TPX

TPY

TPZ

Class Accuracy class according to standard. x x x xεt Turns ratio error (included in class). xε Current ratio error. x x xΔϕ Phase deviation. x x xV-al Rated equivalent excitation limiting

secondary voltage. x

I-al Accuracy limiting secondary excitation current. x

Ie1 Max. allowed secondary excitation current at E1. x

K*Kssc Dimensioning factor (K) multiplied by the rated symmetrical short-circuit current factor (Kssc).

x

ε^ Peak instantaneous error at voltage Emax (calculation see section 10.7 on page 187).

x x

Ktd*Kssc Transient dimensioning factor (Ktd) multiplied by the rated symmetrical short-circuit current factor (Kssc).

x x

Rct DC winding resistance. x x x xTs Secondary time constant (calculation

method see section 10.10 on page 188). x x x x

Kr Remanence factor (calculation see section 10.12 on page 190). x x x


x x x x


99

Parameters assessed for standard IEEE C57.13 (ANSI 30, ANSI 45)

Table 5-28:Parameters assessed for IEEE C57.13 (ANSI)

Parameter Description Parameter assessed for IEEE C57.13

(ANSI)meas. CT prot. CT

Class Accuracy class according to standard. x xε Current ratio error. xε at 20*Isn Current ratio error at 20 times the

secondary current Isn. x

ε at Vb Current ratio error at Vb (see below). xΔϕ Phase deviation. x xVb Rated secondary terminal voltage acc.

to IEEE C57.13. x

Rct DC winding resistance. x xTs Secondary time constant (calculation

method see section 10.10 on page 188). x x



x x

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5.9.2 Conditions for a Positive AssessmentTable 5-29:Conditions for a positive assessment of parameters

Standard Class Conditions for auto-assessment "OK"ANSI

Protection CTs

C Vb: Vb max ≥ Vb rated and Isec (at Vb max) ≥ 20 * Isec ratedVb rated = rated secondary terminal voltage acc. to IEEE C57.13Vb max = terminal voltage at 10% ratio error

Class: Ratio error at I-sn AND 20 * I-sn < 10% ANDratio error at Vb rated < 10%

K Vb: Vb max ≥ Vb rated and Isec (at Vb max) ≥ 20 * Isec ratedVb rated = rated secondary terminal voltage acc. to IEEE C57.13Vb max = terminal voltage at 10% ratio error

Class: Knee-point voltage ≥ 70% of Vb rated (or Vb at 20 * I-sn, if no Vb is entered on the CT-Object card) ANDratio error at I-sn AND 20 * I-sn < 10% ANDratio error at Vb rated < 10%If no value is entered on the CT-Object card, the value for 20 * I-sn * Z (parameter "VA" on the CT-Object card) is displayed.

T Vb: Vb max ≥ Vb rated and Isec (at Vb max) ≥ 20 * Isec ratedVb rated = rated secondary terminal voltage acc. to IEEE C57.13Vb max = terminal voltage at 10% ratio error

Class: Ratio error at I-sn AND 20 * I-sn < 10% ANDratio error at Vb rated < 10%


101

ANSI

Measure-ment CTs

0.3 Class:

0.6 Class:

1.2 Class:

Standard Class Conditions for auto-assessment "OK"

at % of rated current

10% 100% 100%*RF

Ratio error (ε) [%] ≤ 0.6 0.3

Phase error (Δϕ) [min] 2600(RCF-1.006)< Δϕ <

2600(RCF-0.994)

2600(RCF-1.003)< Δϕ <

2600(RCF-0.997)

RCF of the measurement can be calculated from the ratio table:RCF = 1/((Ratio_Error /100) + 1)


10% 100% 100%*RF

Ratio error (ε) [%] ≤ 1.2 0.6


2600(RCF-0.988)

2600(RCF-1.006)< Δϕ <

2600(RCF-0.994)



10% 100% 100%*RF

Ratio error (ε) [%] ≤ 2.4 1.2


2600(RCF-0.976)

2600(RCF-1.012)< Δϕ <

2600(RCF-0.988)


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60044-1

Protection CTs

5P ALF: ALF measured ≥ ALF rated (eg.: measured 27, rated 5P20)

Class: Ratio error at 100% of rated current ≤ 1% andphase at 100% of rated current ≤ 60min andcomposite error (εC) at accuracy limit ≤ 5%

If εC < 5% and is prefixed by a ">" sign (e.g. > εC = 3.200), the class assessment is "n/a".

10P ALF: ALF measured ≥ ALF ratedClass: Ratio error at 100% of rated current ≤ 3% and

composite error (εC) at accuracy limit ≤ 10%


PX Class: Turns ratio error εt ≤ 0.25% (turns ratio error = (N measured - N rated) * 100% / Nrated)

Ek: (Rated knee point e.m.f at 10/50% point)Measured knee point e.m.f. ≥ rated Ek

Ie: Maximum excitation currentMeasured excitation current at rated knee point e.m.f < rated excitation current at the rated knee point e.m.f. (see IEC 60044-1, § 14.4.1).

Kx: Rated dimensioning factor ≤ measured dimensioning factor

Rct: Rated Rct (at Tref) ≥ measured Rct5PR ALF: ALF measured ≥ ALF rated

Class: Ratio error at 100% of rated current ≤ 1% andphase at 100% of rated current ≤ 60min andcomposite error (εC) at accuracy limit ≤ 5%


Kr: Kr ≤ 10%



103

60044-1

Protection CTs (cont.)

10PR ALF: ALF measured ≥ ALF ratedClass: Ratio error at 100% of rated current ≤ 3% and

composite error (εC) at accuracy limit ≤ 10%


Kr: Kr ≤ 10%


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60044-1

Measure-ment CTs

0.2S FS: FS measured ≤ FS rated (eg.: measured 4.3, rated 0.1FS5)

Class: For 100%, 50%, 25% of nominal burden:

0.5S FS: FS measured ≤ FS ratedClass: For 100%, 50%, 25% of nominal burden:

0.1 FS: FS measured ≤ FS ratedClass: For 100%, 50%, 25% of nominal burden:




at % of rated current1% 5% 20% 100% 120%

Ratio error [%] ≤ andphase error [min] ≤

0.7530

0.3515

0.210

0.210

0.210

at % of rated current1% 5% 20% 100% 120%


1.590

0.7545

0.530

0.530

0.530

at % of rated current5% 20% 100% 120%


0.415

0.28

0.15

0.15



0.7530

0.3515

0.210

0.210



1.590

0.7545

0.530

0.530


105

60044-1

Measure-ment CTs (cont.)


3 FS: FS measured ≤ FS ratedClass: For 100%, 50% of nominal burden:

5 FS: FS measured ≤ FS ratedClass: For 100%, 50% of nominal burden:




3180

1.590

160

160

at % of rated current50% 120%

Ratio error [%] ≤ 3 3

at % of rated current50% 120%

Ratio error [%] ≤ 5 5

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60044-6

Protection CTs

TPS Class: Turns ratio error εt ≤ 0.25%(εt = (N measured - N rated) * 100% / N rated)

Val: Val ≥ Val ratedIal: Ial ≤ Ial rated

(Val, Ial: An increase of 10% in Val should not result in an increase of Ial of more than 100%)

Kssc: K * Kssc measured ≥ K * Kssc ratedRct: Rct (at Tref) ≤ Rct rated

TPX Class: Ratio error at rated current ≤ 0.5% andphase at rated current ≤ ±30min andεpeak at accuracy limit (Kssc * Ktd) ≤ 10%

If εpeak < 10% and is prefixed by a ">" sign (e.g. > εpeak = 3.200), the class assessment is "n/a"

Kssc: Ktd * Kssc measured ≥ Kssc * Ktd ratedRct: Rct (at Tref) ≤ Rct rated

TPY Class: Ratio error at rated current ≤ 1.0% andphase at rated current ≤ ±60min andεpeak at accuracy limit (Kssc * Ktd) ≤ 10%

If εpeak < 10% and is prefixed by a ">" sign (e.g. > εpeak = 3.200), the class assessment is "n/a"

Kssc: Ktd * Kssc measured ≥ Kssc * Ktd ratedTs: Ts ≤ ±30% of Ts ratedKr: Kr ≤ 10%Rct: Rct (at Tref) ≤ Rct rated

TPZ Class: Ratio error at rated current ≤ 1.0% andphase at rated current ≤ 180 ± 18min

Kssc: Ktd * Kssc measured ≥ Kssc * Ktd ratedTs: Ts ≤ ±10% of Ts ratedRct: Rct (at Tref) ≤ Rct rated



107

5.10 Comment CardThe Comment card is only available if it is enabled in the Select Cards page (Default Test Card Selection or S E L E C T C A R D S soft key in the CT-Object card).

In the Comment card you can enter any text, e.g. additional notes regarding the current test.

Figure 5-33:Comment card

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CT Analyzer PC Tools

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6 CT Analyzer PC ToolsThe CT Analyzer PC Toolset contains a set of PC software that is necessary and helpful for your work with the CT Analyzer on a PC.

The following tools are installed with the CT Analyzer PC Toolset:

• CTA Start Page

• CTA QuickTest

• CTA Remote Excel File Loader

• Update for CPC Explorer (if installed)

• CTA Remote Control

• Sample software for CTA Remote Control

• CTA remote test sample for Visual Basic (VBA)

• CTA remote test sample for C++

• CTA to Netsim Export

6.1 System RequirementsThe software of the CT Analyzer PC Toolset requires the following software installed on the system:

• Operating system: Windows 2000 SP4, Windows XP SP2, Windows Vista SP1.

• Microsoft Office® (required for CTA Remote Excel File Loader and CTA Remote Control software):Office 2000 SRxx, Office 2002 (XP) SR xx, Office 2003 SRxx or Office 2007 SRxx.

Note: The operating systems Windows 2000 and Windows XP require administrative rights for your local machine.

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6.2 Installation of the CT Analyzer PC Toolset6.2.1 Installing the CT Analyzer PC Toolset

The CT Analyzer PC Toolset and its installation program Setup Wizard are included on the CD ROM "CT Analyzer PC Toolset" accompanying the CT Analyzer. Proceed as follows to install the CT Analyzer PC Toolset:

1. Exit all other major programs running on your computer.

2. Insert the "CT Analyzer PC Toolset" CD ROM into your computer’s CD ROM drive. The Setup Wizard starts automatically.

3. Follow the instructions displayed on the screen to install the software.

6.2.2 Update for CPC ExplorerIf you have the CPC Explorer installed on your PC, it will be updated during the installation of the CT Analyzer PC Toolset. The CPC Explorer software is not included in the CT Analyzer PC Toolset. It has to be installed separately from the CD ROM "CPC Explorer Software" accompanying the CT Analyzer.

Refer to section 6.9 on page 138 for a detailed description of the CPC Explorer.

Note: Should the Setup Wizard not start automatically a few seconds after the CD has been inserted into the CD ROM drive, change to the Windows Explorer and double-click setup.exe at the "CT Analyzer PC Toolset" CD ROM.


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6.3 The CTA Start PageThe CTA Start Page is the central organizing element for the PC software tools available for the CT Analyzer. It is a window with a functionality similar to that of a web page.

There are two ways to launch the CTA Start Page:

• Click the Programs | OMICRON | CT Analyzer | CTA Start Page command in the Windows Start menu.

• Double-click the "CTA Start Page" desktop icon .

Figure 6-1:CTA Start Page

The functionality of the CTA Start Page is described below.

Click www.omicron.at to visit the OMICRON website.

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6.3.1 Version Number and "Updates available!" LinkThe header area of the CTA Start Page shows the version of the installed CT Analyzer PC Toolset software and a hyperlink Update available!, if updates are available on the OMICRON website.

Clicking Update available! opens the OMICRON News window providing messages and news relevant to the CT Analyzer and the CT Analyzer PC Toolset software. Here you can download available software updates. For a detailed description of the OMICRON News window, please refer to page 114.

6.3.2 CT Analyzer Tools

CTA QuickTestClick this entry to start the software tool CTA QuickTest. Using the CTA QuickTest software, the CT Analyzer can be used as a versatile multimeter with included power source.

Refer to section 6.4 on page 116 for a detailed description of this tool.

CTA Remote Excel File LoaderClick this entry to start the software tool CTA Remote Excel File Loader. Using this software, it is for example possible to

• prepare and edit tests on the PC and to upload and download such tests from/to the CT Analyzer,

• import CT Analyzer report files into Microsoft Excel,

• prepare customer-specific test reports, etc.


CPC ExplorerThis entry is only active, if the CPC Explorer software is installed on the PC. If active, click this entry to start the software tool.

The CPC Explorer software is not included in the CT Analyzer PC Toolset. It has to be installed separately from the CD ROM "CPC Explorer Software" accompanying the CT Analyzer. Refer to section 6.9 on page 138 for a detailed description of this tool.


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6.3.3 Setup

Firmware UpdateClick this entry to start the CT Analyzer Firmware Update tool. This tool establishes communication with a connected CT Analyzer and enables you to read e.g. the serial number and the current version of the firmware and/or to perform a firmware update or install a new user interface language file.


SettingsClicking this entry displays the Settings dialog box where you can define the following:

"General" tab

In the General tab you can select the user interface language for the software components of the CT Analyzer PC Toolset and the CTA Start Page.

"Remote EFL" tab

Using the "Use custom template" checkbox you can select whether the CTA Remote Excel File Loader tool should use a custom template file or an OMICRON template file by default. Depending on your selection, specify the path and name of the default template and/or the custom template in the corresponding text field.

"News Window" tab

In this tab you can select whether you want to have the messages of the OMICRON News service displayed "Daily", "Only if new messages are available" or "Never". Furthermore, you can open the OMICRON News window by clicking the button S H O W N E W S N O W.

For a more deteiled description of the OMICRON News window, please refer to page 114.

Note: The OMICRON template file CT Remote EFL.xlt is by default stored in a subfolder in the installation path of the CT Analyzer PC Toolset. If not changed during installation, the path is:C:\Program Files\OMICRON\CT Analyzer PC Toolset\RemoteEFL\CT Remote EFL.xlt

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6.3.4 Support

Manuals, Samples, Templates, FirmwareClicking one of these entries opens the Windows Explorer showing the respective default folder for the manuals, samples, CTA Remote Excel File Loader templates and firmware files delivered by OMICRON and installed during the installation of the software.

OMICRON NewsClicking this entry opens the OMICRON News window. OMICRON News is an information service that provides you with relevant messages such as updates for your installed OMICRON products as well as OMICRON product information and news.

This service bases on the RSS Dynamic Bookmark Technology. To use this service, your computer needs access to the Internet. If your computer has no Internet access, the OMICRON News window will not start.

The upper part of the OMCRON News window lists descriptive headlines of the available updates and news. The lower part is a browser-like window that displays the contents of the topic you select in the upper part.

Note: If not changed during installation, the path is:C:\Program Files\OMICRON\CT Analyzer PC Toolset\...

"Show Updates" Enable/disable the display of relevant update messages concerning your CT Analyzer PC Toolset installation.

"Show News" Enable/disable the display of OMICRON product news.

"Only Unread" Select to display unread update messages and news, only. Read messages are hidden.

"Show New Messages"

Here you can select to only display update messages and news that were published after your last visit at the OMICRON news server. If selected, messages before that date are hidden.

M A R K A L L A S R E A D andM A R K A L L A S U N R E A D

Marks all update messages and news as read or unread.


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Opens the Settings dialog box where you can define the following settings:

Select "Daily" to visit the OMICRON news server once a day.

Select "Only if new messages available" to only start the OMICRON News window when the OMICRON news server holds updates/news that are newer that the ones on your computer.

Select "Never" to disable the start of the OMICRON News window. Nevertheless, when your computer accesses the Internet, the OMICRON news server is checked for updates.

At "News Language" and "UI Language", select the language for the news and the user interface language for the CTA Start Page and the software tools started from the CTA Start Page.

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6.4 CTA QuickTestUsing the CTA QuickTest software, the CT Analyzer can be used as a versatile multimeter with included power source.

6.4.1 Starting CTA QuickTestStart the CTA QuickTest software by clicking its entry in the CTA Start Page.

6.4.2 Using CTA QuickTestFigure 6-2:CTA QuickTest


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Output adjustmentFigure 6-3:CTA QuickTest, Output group box

Table 6-1:User interface elements in the Output group box UI element Description

Mode The generator can be configured as AC or DC source. Select the corresponding radio button.

V/I The generator can work either in voltage or current mode. Select the corresponding radio button.

Amplitude Mode "AC" and "V" (voltage source): 0 to 35V

Mode "DC" and "V" (voltage source): 0 to 120V

Mode "AC" and "I" (current source): 0 to 5A

Mode "DC" and "I" (current source): 0 to 10A

Attention: DC current mode is very dangerous! It is not possible to interrupt the circuit using a standard relay or a standard circuit breaker. Due to the arc, contact clearances of up to 10mm are required to switch off the current.

Frequency Output frequency of the generator.

Possible values: 10 to 400Hz.Compensate SEC impedance

Measurement input SEC of the CT Analyzer has an input impedance of approx. 470kΩ and can thus influence the current measurement.

Therefore, it is possible to compensate this error current by clicking the checkbox "Compensate SEC impedance". This checkbox is marked by default.

Note: The input impedance of input PRIM is even lower but cannot be compensated.

ON / OFF button Click this button to start or stop the measurement.

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Measurement ModeFigure 6-4:CTA QuickTest, Measurement Mode group box

Table 6-2:User interface elements in the Measurement Mode group box

UI element DescriptionRMS Performs a standard true rms measurement of the AC

signal component only. The DC part is removed from the measured rms result.

Frequency selective Only the fundamental wave of the applied signals is measured.

Frequency selective (with filter)

Cutoff Frequency

Allows high precision measurement of the fundamental wave of an applied signal. All frequencies outside the output frequency plus/minus the cutoff frequency are supressed by about 120dB.

Depending on the selected cutoff frequency, the measurement time can differ considerably. The typical time needed for a frequency selective measurement depends on the cutoff frequency as follows:

Cutoff frequency Measurement time0.2Hz approx. 1 minute1.5Hz approx. 15 seconds 10Hz approx. 3 seconds

Integration Time The integration time can be selected in the range between 0.1 and 1sec.

If the measurement mode "Frequency selective (with filter)" is used, the software will automatically choose an approprate integration time depending on the selected cutoff frequency.

Regulation Parameters

Only used for AC mode. Inactive in DC mode.

If the "Inductive load" checkbox is checked, the output generator always tries to keep the DC output current at zero. For this purpose, a current regulator is permanently running while an AC signal is generated.

continued ...


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Measurement areaFigure 6-5:CTA QuickTest, Measurement area

Table 6-3:User interface elements in the Measurement area

(cont.) To guarantee proper operation of the current regulator, the connected load (L and R) has to be defined under "Regulation Parameters". If you don't know the actual inductance and resistance of the load, use the default values (R = 1Ω, L = 50H). In this case, the regulator will also regulate the DC current to zero, however it will need longer to reach this.

UI element Description

UI element DescriptionColumn "SEC" Voltage input SEC.

Input voltage ranges (automatic range selection): 0 to 0.3VAC, 0 to 3VAC, 0 to 30VAC, 0 to 300VAC

Input impedance:470kΩ to 1MΩ depending on the applied signal

Column "PRIM" Voltage input PRIM.

Input voltage ranges (automatic range selection): 0 to 0.03VAC, 0 to 0.3VAC, 0 to 30VAC

Input impedance:130kΩ to 330kΩ depending on the applied signal

Column "Output (A)" Current measurement.

Input voltage ranges (automatic range selection): 0 to 150mA, 0 to 1.5A, 0 to 3A, 0 to 15A peak

The input impedance of input SEC can be compensated. Measurement is done using a series shunt in the generator output.

Row "Range" Displays the actually used voltage/current range.

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ResultsFigure 6-6:CTA QuickTest, Results group box

Table 6-4:User interface elements in the Results group box

Row "DC" DC amplitude of the applied signal.Row "RMS" RMS amplitude of the applied signal after the selected

filter.Row "Peak +" Measured positive peak value of the applied signal.Row "Peak -" Measured negative peak value of the applied signal.Row "Phase" Phase relative to input SEC (the phase of input SEC is

always 0).Row "Frequency" Measured frequency.


UI element DescriptionN (Vsec/Vprim) N = VSEC/VPRIM

Z (Vsec/I) Z = VSEC/IOUTPUT

cos(phi) cos(IPHASE)

L or CPhase I = 0 - 360° -->

Phase I = 0 - 180° -->

XL or XCPhase I = 0 - 360° -->

Phase I = 0 - 180° -->

R

LXLω------=

C 1ω XC⋅---------------=

XL 1 αI PHASEcos( )2– Z⋅=

XC 1 αI PHASEcos( )2– Z⋅=

R αI PHASEcos Z⋅=


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Save ResultsThe results can be saved to a *.csv file for later use for documentation purposes or further calculations.

Figure 6-7:CTA QuickTest, Save Results group box

Table 6-5:User interface elements in the Save Results group box

Connection StatusFigure 6-8:CTA QuickTest, connection status information

Using the button D I S C O N N E C T / CO N N E C T you can disconnect/connect to the CT Analyzer. Connection is established automatically upon startup of the CTA QuickTest software, if a CT Analyzer is detected on a USB port.

The status field on the bottom left side displays to which device the software has connected.

The status field on the bottom right side displays whether the connection is still established.

Click E X I T to exit CTA QuickTest and to return to the CTA Start Page.

UI element DescriptionAdd Comment A comment can be entered for each test.Decimal symbol Character used as decimal separator when storing

data to the *.csv file.S A V E button Click to save the actual values to the currently open

file. If no file is currently open, the "Save As" dialog will appear.

S A V E A S button Click to save the actual values to a new file. The "Save As" dialog appears where you can specify the file.

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Menu optionsFigure 6-9:CTA QuickTest, menu bar

Table 6-6:Menu options available in CTA QuickTest Menu Description

F I L E menu Using the options C O N N E C T and D I S C O N N E C T you can connect/disconnect to the CT Analyzer (see also button C O N N E C T / D I S C O N N E C T ).

Using the options S A V E R E S U L T S and S A V E R E S U L T S A S you can save the actual values to the currently open file or to a new file. If necessary, the "Save As" dialog appears where you can specify the file (see also buttons S A V E and S A V E A S).

Using E X I T you can exit CTA QuickTest and return to the CTA Start Page (see also button E X I T ).

? menu Click the menu option A B O U T C T A Q U I C KT E S T to open a dialog showing detailed version information about CTA QuickTest.


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6.5 CTA Remote Excel File LoaderThe CTA Remote Excel File Loader is used to:

• prepare and edit tests with Microsoft Excel© on your computer,

• communicate with the CT Analyzer,

• import CT Analyzer report files (*.xml) into Microsoft Excel©,

• upload/download tests to and from the CT Analyzer,

• prepare customer-specific test reports,

• develop test automation under VBA.

The CTA Remote Excel File Loader performs remote-controlled tests with the CT Analyzer. The tool can be extended further to a customer-specific report tool for the CT Analyzer.

Post-processing of the results is easy, since the results are converted into Microsoft Excel-compatible numbers. In a separate blank worksheet or customer-specific test report, you can reference to the data of the OMICRON pre-made worksheets using Microsoft Excel formulas. When the data in the OMICRON worksheets are updated, Microsoft Excel also updates the customer-made worksheets. By this method, it is possible to create customer-specific Microsoft Excel templates for different applications.

6.5.1 Starting the CTA Remote Excel File LoaderStart the CTA Remote Excel File Loader by clicking its entry in the CTA Start Page. A safety warning appears on the screen, notifying you that the file contains macros. Click A C T I V A T E M A C R O S to continue.

Note: The data sheet of the CTA Remote Excel File Loader holds all data the CT Analyzer can deliver. However, it is not intended to provide a printable test report. In order to obtain a printable test report, you can either add an additional worksheet and create your own printable test report or use one of the pre-made templates delivered by OMICRON.

If you did not change the default installation path of the software, these templates are located under: C:\Program Files\OMICRON\CT Analyzer PC Toolset\RemoteEFL\Templates

You can also access the Templates folder by clicking the Templates entry in the Support section of the CTA Start Page.

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The Welcome page of the CTA Remote Excel File Loader provides the following functionality:

• Click the N E W T E S T button to start your measurements with the CT Analyzer using the defined test settings.

• Click the L O A D R E P O R T button to load previously saved CT Analyzer report files (*.xml).

• Click the H E L P button to launch the CTA Remote Excel File Loader help.Figure 6-10:CTA Remote Excel File Loader Welcome page

Note: Upon starting, the CTA Remote Excel File Loader performs a Microsoft Excel© version check. If the Excel© version installed on your system is too old, a corresponding message is displayed, notifying you that that you have to upgrade your Excel version in order to run the CTA Remote Excel File Loader. Also refer to the system requirements given in section 6.1 on page 109.


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6.5.2 Data SheetThe CTA Remote Excel File Loader data sheet shows all test settings, test parameters and test results. The intention of this data sheet is to have all data the CT Analyzer can deliver available on one sheet. It is not intended to provide a printable test report.

For a printable test report, you can either use one of the templates delivered by OMICRON or add an additional worksheet and create your own printable test report by inserting references to the required parameters in the data sheet and formatting the worksheet accordingly.

Moving the mouse cursor on a parameter name cell marked with a small red corner opens a comment box showing additional explanations about this parameter.

Figure 6-11:CTA Remote Excel File Loader data sheet

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Click the L O A D R E P O R T button to load a previously saved CT Analyzer report file (*.xml).

Click the S E T T I N G S button or one of the cells highlighted by blue background to open the Test Settings dialog box (refer to Figure 6-12) and make or change the test settings.

Click the S T A R T T E S T button to immediately download the test settings to the connected CT Analyzer and start the execution of the specified test.

Test Settings dialogFigure 6-12:CTA Remote Excel File Loader, Test Settings dialog box

The Test Settings dialog box holds all parameters contained in the CT Analyzer’s CT-Object card. For a detailed description of the parameters, please refer to section 5.4.3 on page 58.

To edit the content of the fields "Location" and "Object", click the corresponding browse button to open the Location dialog or the Object dialog, respectively. For a more detailed description of the "Location" and "Object" settings, please refer to section 5.4.2 on page 57.


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Changing the test settings in this dialog is only possible after clicking the C H A N G E S E T T I N G S button.

Table 6-7:Buttons in the Test Settings dialog box

Button DescriptionE D I T R E P O R T Click to edit the location, object and comment fields of a

CT Analyzer report (= version 3.00). Changes to test settings or test results are not allowed.

S A V E R E P O R T A S

Click to save the report under a name of your choice.

C H A N G E S E T T I N G S

Click to change the test settings. Note that this does not affect the report area of the worksheet or the embedded report data.

S A V E S E T T I N G S A S

Click to save the settings to a settings file. This settings file can later be used as test template by the CT Analyzer or the CTA Remote Excel File Loader.

Each report file can also be used as a settings file. Settings files are much smaller than report files.

O P T I O N S Opens the Options dialog box. Please refer to ”Options dialog” on page 128.

L O A D F I L E Click to load any CT Analyzer test report or settings file of your choice into the actual worksheet.

A P P L Y Click to apply the actual changes to the worksheet. If you edited a report, the changes will be applied to both the settings area and the report area of the worksheet. Futhermore, the embedded report is changed.

Once you applied the actual changes, the C A N C E L button changes into E X I T .

C A N C E L /E X I T

Click C A N C E L to discard all actual changes and close the Test Settings dialog box.

Click E X I T to close the Test Settings dialog box.S T A R T T E S T /S T O P T E S T

Click S T A R T T E S T to apply the changes and start the execution of the test on the CT Analyzer. Once you have started the test, this button changes to S T O P T E S T .

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Options dialogFigure 6-13:CTA Remote Excel File Loader, Options dialog box

The Options dialog is displayed, if you click the O P T I O N S button in the Test Settings dialog box.

Click O K to apply your changes and close the dialog or C A N C E L to close the dialog without changing the options.

Table 6-8:Buttons in the Options dialog box

Button DescriptionAutosave to Serialno_Tap

Select this option to automatically save the result files on your computer.

The resulting file names are a combination of the file name and the tap description (e.g. 1S1-1S2), separated by an underscore character. Characters that are not allowed in filenames are automatically replaced by a minus character.

If you already saved a file, the file path of the last saved file is used. When selecting this option for the first time or when opening the template for the first time, a "Save as" dialog is displayed.

Example: File name: 08/58572926Tap: 1S1-1S2

The results are saved to the file 08-58572926_1S1-1S2 in the folder of the last saved file.


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6.5.3 Using User-Defined Code in the CTA Remote Excel File LoaderIt is possible to extend the CTA Remote Excel File Loader templates used for communicating with the CT Analyzer by user-defined Visual Basic (VBA) code in order to execute this code after the creation of a new current transformer (CT) data sheet or after filling a CT data sheet with data.

Creating a new CT data sheet is done by pressing the N E W T E S T button on the Welcome worksheet whereas filling a CT data sheet can be accomplished using different methods.

For instance, one possibility is to load measurement results by clicking the L O A D R E P O R T button in the Welcome worksheet. Or, as an alternative, in the Test Settings dialog of the CTA Remote Excel File Loader it is possible to load CT settings or measurement results from an existing CT file in the file system or to execute a CT test (buttons C H A N G E S E T T I N G S , L O A D R E P O R T , S T A R T T E S T , A P P L Y ). The currently active CT data sheet is then filled with the corresponding CT data.

The execution of user-defined code is started as soon as the creation of a new CT data sheet or the filling of the active CT data sheet is finished. For this, two different VBA methods can be used that are called by the runtime environment of the used Excel template. Both methods can be found in the VBA module mdlMainAndTools of the used Excel template. Brief descriptions of these methods are given below.

Disable Save Results Dialog

Starting a new test usually launches a query whether the existing worksheet data should be overwritten. Select this option to suppress the query and to overwrite the existing worksheet data without further notification.

USB port

COM port

Determine the interface for the communication with the CT Analyzer: USB port or COM port.

If "USB port" is selected and no device can be found on the USB port, the software automatically attempts to locate a device on the COM port, and vice versa.

Language The CTA Remote Excel File Loader supports several user interface languages. From the "Language" box, select a language of your choice. The language can be changed at runtime. Apart from the user interface, this selection also changes the language of the data sheets.

Button Description

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Within these two functions, VBA source code can be embedded to handle these events and to perform required user-defined tasks (see comment "enter your code to be executed…"). The code is protected by error handling in order to handle occurring exceptions and to show an appropriate message.

User-defined code, called after the creation of a new CT data sheet:' -------------------------------------------------------

' function for user-defined code after data sheet is created

Public Function DoUserCodeAfterDataSheetCreation() As Long

On Error GoTo ErrHnd

Dim lRet As Long ' return value

lRet = 0 ' init

' enter your code to be executed after data sheet is created

DoUserCodeAfterDataSheetCreation = lRet

Exit Function

ErrHnd:

MsgBox "Error occured: " & Err.Number & ", " & Err.Description

End Function

User-defined code, called after a CT data sheet has been filled with CT data:' -------------------------------------------------------------

' function for user-defined code after sheet is filled with data

Public Function DoUserCodeAfterDataSheetIsFilled() As Long

On Error GoTo ErrHnd

Dim lRet As Long ' return value

lRet = 0 ' init

' enter your code to be executed after data is filled into sheet

DoUserCodeAfterDataSheetIsFilled = lRet

Exit Function

ErrHnd:

MsgBox "Error occured: " & Err.Number & ", " & Err.Description

End Function


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6.6 CT Analyzer Firmware Update ToolThe CT Analyzer Firmware Update tool can be used as an alternative to the functions "Update Firmware" and "Update Text" of the CT Analyzer (refer to section 5.3.4 on page 52) to update the firmware of the CT Analyzer or to install a new user interface language file.

The CT Analyzer Firmware Update tool establishes communication with a connected CT Analyzer and enables you to

• read the serial number and the current firmware version from the connected CT Analyzer,

• perform an update of the firmware and to

• install a new user interface language file on the CT Analyzer.

6.6.1 General Information About Updating the Firmware and the User Interface Language Files

About updating the firmwareTo update the firmware, a corresponding firmware file CTAnalyzer*.bin has to be available.

About updating user interface language filesEnglish is contained in the firmware and does not require a user interface language file. To install a new language, it is necessary to update the user interface language installed on the CT Analyzer with the corresponding file CTUser_xxx.bin (xxx stands for the version and the language, e.g. "V2_00_Deu" for version 2.00, German).

Attention: It is also possible to install older firmware. In this case, the user interface text is deleted and the device automatically changes to the English user interface. After you have downgraded the firmware, you also have to install the user interface language file of this (older) firmware package.

After an installation of new firmware, the user interface language automatically changes to English, if the installed user interface text is no longer compatible. If you are using a user interface language other than English, install the corresponding new user interface language file delivered with the new firmware.

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If the text update process is interrupted or fails, the device displays an error message and automatically resets the user interface to English when it is switched on the next time.

6.6.2 Starting the CT Analyzer Firmware Update ToolTo start the CT Analyzer Firmware Update tool, click the entry Firmware Update on the CTA Start Page. The software then automatically scans the USB ports of the PC for a connected CT Analyzer.

If it is not able to find a CT Analyzer on one of the USB ports, a dialog box is displayed where you can select a serial port.

Select the serial port the CT Analyzer is connected to and then click C O N N E C T . To abort the connection establishment, click the C A N C E L button.

Figure 6-14:Dialog for manual selection of a serial port

Attention: Only install language files that are included in the package of the installed firmware version.

If you install a language file that does not belong to the same package, the user interface may become unreadable.

Note: Refer to the OMICRON website for available languages or ask your distributor for a special language file.


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6.6.3 Using the CT Analyzer Firmware Update ToolFigure 6-15:CT Analyzer Firmware Update dialog box

Connected deviceThe content of these fields is read from the connected CT Analyzer. The information displayed in these fields cannot be edited.

Figure 6-16:CT Analyzer Firmware Update, Connected device group box

Table 6-9:User interface elements in the Connected device group box

UI element DescriptionSerial number Serial number of the connected CT Analyzer.Connected over PC port the CT Analyzer is connected to: USB port or

one of the serial COM ports.Installed firmware version

Firmware version read from the CT Analyzer

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Choose .zip file containing firmware filesIf you received a .zip file containing the update files, uncheck the "Select files manually" checkbox (see Figure 6-18) to activate this field.

Click the B R O W S E button to navigate to the .zip file and select it. The path and the file name of the .zip file are displayed in the field.

Click the U P D A T E button to start the update process. A language selection dialog for the user interface language to be installed on the CT Analyzer is displayed. Select the desired language and click O K to continue. The software then automatically loads the files required for the update of the CT Analyzer from the .zip file.

Figure 6-17:CT Analyzer Firmware Update, selecting a zip file containing firmware files

Selected filesIf you don’t have the update files available in a .zip file (see "Choose .zip file containing firmware files" above), you have to specify the firmware file and the user interface language file to be used for the update manually.

Figure 6-18:CT Analyzer Firmware Update, Selected files group box

Table 6-10:User interface elements in the Selected files group box

UI element DescriptionSelect files manually

If checked, you can specify the firmware file and the user interface language file used to update the CT Analyzer individually.

Firmware file To update the firmware, click the corresponding B R O W S E button to navigate to the desired firmware file CTAnalyzer*.bin and select it. The path and the file name are displayed in the field.

Please note the general information given in section 6.6.1 on page 131.


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Update methodUsing these options you can select whether you want to update the firmware and the user interface language file or the user interface language file only.

Figure 6-19:CT Analyzer Firmware Update, Update method group box

Buttons and progress indicationFigure 6-20:CT Analyzer Firmware Update, buttons and progress indication

Click C L O S E to close the CT Analyzer Firmware Update tool.

Click U P D A T E to start the update process for the CT Analyzer (firmware and user interface language update or user interface language update only).

The "Progress" bar shows the progress of the running update process.

User interface file To install a new language, click the corresponding B R O W S E button to navigate to the desired firmware file CTUser_xxx.bin and select it. The path and the file name are displayed in the field.

Please note the general information given in section 6.6.1 on page 131.


Note: The firmware update process may take some minutes. If the update process is interrupted or fails, switch the CT Analyzer off and on again. The device then tries to perform the firmware update from the Compact Flash card.

In this case, this firmware update can no longer be performed from the PC. Copy the file CTAnalyzer*.bin and the corresponding language file to the OMICRON directory on the Compact Flash card and use the update functions in the CT Analyzer (see section 5.3.4 on page 52).

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6.7 CTA Remote Control SoftwareThe CTA Remote Control Software is used to remote control CT Analyzer test sets via PC. It does not offer a graphical user interface and can be operated using all common programming languages.

Refer to the "CTA Remote Control Manual" for a detailed description of the remote software and how to use it.

6.7.1 Sample Software for CTA Remote ControlThe remote sample software is an example for the CTA Remote Control to show how to control the CT Analyzer and how to create a customer-specific report.

All important functions of the CTA Remote Control are included in this sample to enable the user to easily extend the functionality.

The intention of this tool is to help the user to create his own customer-specific report tool for the CT Analyzer.

Figure 6-21:Sample software main screen with settings area


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6.8 CTA to NetSim Export ToolAfter installing the CT Analyzer PC Toolset, it is possible to export the CT Analyzer test results as a transformer model for the OMICRON NetSim test module.

When you right click an *.xml file in the Windows Explorer, you will find the list entry E X T R A C T C T A N A L Y Z E R R E S U L T S T O O M I C R O N N E T S I M in the context menu.

Figure 6-22:Context menu of the Windows Explorer for *.xml files

If you select this entry, a message dialog appears, notifying you that the data were exported for use in NetSim.

Within NetSim you can use the CT data by selecting the menu item P A R A M E T E R | C U R R E N T T R A N S F O R M E R .

Figure 6-23:Message after exporting the results for use in NetSim

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6.9 CPC Explorer for CT Analyzer6.9.1 General

This section refers to the CPC Explorer software version V 1.40 or higher.

The CPC Explorer is a PC-based software program that is shipped with both the primary test system CPC 100 and the CT Analyzer. With the CT Analyzer, use it to browse the files stored on the Compact Flash card.

Since the CPC Explorer was initially developed for the CPC 100, it contains functions that are not needed for the CT Analyzer. For the CT Analyzer, some of these functions are disabled in the CPC Explorer user interface.

6.9.2 Installation of the CPC Explorer Software

Minimum Computer Requirements• Pentium 200MHz

• 64MB RAM

• CD ROM drive

• Windows 2000/XP and Internet Explorer version 5.5 or higher.

Installing the CPC ExplorerThe CPC Explorer software and its installation program Setup Wizard are included on the CD-ROM "CPC Explorer software" accompanying the CT Analyzer.

To start the CPC Explorer installation:

1. Exit all other major programs running on your computer.

2. Insert the "CPC Explorer software" compact disc into your computer’s CD-ROM drive. The Setup Wizard starts automatically displaying the CPC Explorer start screen.

3. Follow the instructions displayed on the screen to install the software.

Note: The operating systems Windows 2000 and Windows XP require administrative rights for your local machine.

Note: Should the Setup Wizard not start automatically a few seconds after the CD has been inserted into the CD ROM drive, change to the Windows Explorer and double-click setup.exe at the "CPC Explorer software" CD ROM.


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6.9.3 Using the CPC Explorer with the CT AnalyzerThe CT Analyzer automatically saves all files to the Compact Flash card in XML format. By reading the CF card with your PC, the test reports can be browsed, viewed or edited on your PC using the CPC Explorer software.

Apart from the pull-down menus and the toolbar, the CPC Explorer interface consists of three panes:

• The top left pane is only used for the primary test system CPC 100 to display the files of all connected CPC 100 units. With the CT Analyzer it remains empty as long as no CPC 100 is connected.

• The bottom left-hand side pane displays the files of the PC.

• The right-hand side pane displays the contents of any CT Analyzer XML document selected in the left-hand side pane.

Figure 6-24:CPC Explorer user interface

The file contents are displayed in the right-hand side pane.

Area for display of CPC 100 files (empty, if used with CT Analyzer).

File browser area

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Viewing FilesThe representation of the file contents in the right-hand side pane of the CPC Explorer is generated on the basis of a stylesheet (also refer to ”Default Stylesheet” on page 141).

To display a file on the PC, either right-click on the file name and select V I E W from the context-menu, or double-click the file name.

If you select a folder rather than a single test, right-click the folder name and select V I E W from the context-menu. The contents of all tests of the entire folder structure will be displayed in the right-hand side pane.

The toolbar buttons

Clicking on the right-hand side pane activates the file-specific buttons in the toolbar. Otherwise, these buttons are grayed-out.

The R E F R E S H button renews the display of the left-hand side pane.

The P R I N T button brings up the Print dialog box.

The F O N T button changes the size of the font with which the file in the right-hand side pane is displayed:

• Clicking the F O N T button changes the size of the font to the largest available.

• Clicking on the "down" symbol on the right-hand side of the button displays a list of available font sizes.

Clicking on the "down" symbol on the right-hand side of the E D I T button displays the available applications to edit the displayed HTML file.

1. Choose E D I T W I T H M I C R O S O F T W O R D F O R W I N D O W S to start the application MS Word for Windows and load the HTML file of the displayed report.

2. Choose E D I T W I T H M S H T M L E D I T O R to edit the displayed report in the WYSIWYG1 HTML editor.

Contrary to editing the report with MS Word for Windows, the MSHTML mode does not start an application. Instead, the cursor moves directly to the beginning of the first line of the report displayed in the right-hand side pane, and enables direct editing of the test report.

Note: MS Word for Windows 97 and previous versions do not support editing HTML files.

1. WYSIWYG = what you see is what you get


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About the MSHTML editor:• Select the menu item E D I T | I N S E R T P A G E B R E A K to enter a page

break at the cursor’s position. In the test report view, this page break is represented by a horizontal line. When printed out, the printer then starts a new page at every inserted page break. The horizontal line itself is not printed.

• A right mouse click into the test report view opens a context menu which provides a cut/copyand paste functionality as known from other Windows applications.

The CPC Explorer will not allow you to directly modify the original test report. The only way to save your changes is saving the file with a new name.

OptionsTo open the Options dialog box, select T O O L S | O P T I O N S from the pull-down menu. In this dialog box you can customize the CPC Explorer user interface.

Language

You can change the language of the CPC Explorer user interface. The CPC Explorer re-starts automatically showing the user interface in the selected language.

Default Stylesheet

Stylesheets describe how test reports are represented on screens or in print. A stylesheet contains formatting information, and offers the possibility to influence the presentation of test reports.

Upon request, OMICRON can provide you with customized XSL stylesheets1. To apply a stylesheet, enter the path to this file into the entry field "Stylesheet", or click B R O W S E to search for it.

You can specify your own stylesheet in order to customize the representation of the test reports in the right-hand side pane.

This documentation, however, will not describe how to create new stylesheets. For more detailed information about XML, XSL and HTML please refer to specialized literature and/or special websites, or contact the OMICRON customer support.

1. EXtensible Stylesheet Language

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Application Examples

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7 Application ExamplesThe grounded terminal on the secondary side of the CT always has to be connected to the black sockets of input "Sec" and the "Output" of the CT Analyzer. Connecting the red sockets of the CT Analyzer to PE can result in incorrect measurement and/or cause an automatic abortion of the measurement with an error message.

7.1 Measurement at a Freely Accessible CTProceed as follows to perform measurements at a freely accessible CT (refer to Figure 7-1):

1. Connect the CT Analyzer’s equipotential terminal to protective earth (PE).

2. Connect one terminal on the primary side and one terminal on the secondary side of the CT to PE.

It is absolutely important to avoid coupling of interferences into the primary circuit during measurement. Therefore, connect the side of the primary circuit that is able to receive more interferences to PE (e.g. the side with the longer line length). The ungrounded side should be the side that receives less interferences.

3. Make sure that all other terminals of the CT are disconnected from the utility lines, except the ones that are connected to PE.

4. Connect the secondary side of the CT to the "Output" sockets and input "Sec" of the CT Analyzer:

• Connect that side of the CT that is connected to PE to the black sockets of the CT Analyzer.

• Connect that side of the CT that is open to the red sockets of the CT Analyzer.

5. Connect the primary side of the CT to CT Analyzer input "Prim". Make sure that the polarity is correct (same colors on same polarity).

6. Start the test.

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Figure 7-1:Measurement at a freely accessible CT Utility line Utility line

BurdenCoax measurement cables


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7.2 Measurement at a Delta Winding TransformerMeasurement of CT's in delta-connected transformer windings is indeed possible, but the measurement results are not very accurate and strongly depend on the symmetry of the transformer windings.

For such measurements the current injection method is not suitable, since the transformer windings are connected in series to the primary side of the CT. This method would require very big test equipment which is able to generate a current of several 100A at very high voltages. This is why the voltage injection method as it is used by the CT Analyzer is the only suitable method to perform such measurements.

When measuring a CT inside of such a configuration, input "Prim" of the CT Analyzer has to be connected to both sides of the series connection consisting of the CT’s primary side and the particular transformer winding (refer to Figure 7-2, terminals L1 and L3). Since the delta-connected windings act as a voltage divider, it is not possible to read the CT winding ratio directly. To obtain the correct transfer ratio, the ratio value determined by the CT Analyzer has to be corrected.

For this purpose, the CT Analyzer allows to set a so-called delta compensation on the CT-Object card. Select the appropriate compensation depending on the transformer terminals you are using for the CT primary signal measurement.

Refer to the example given in Figure 7-2: If you have connected CT Analyzer input PRIM to L1 and L3, you should select the delta compensation value "Ratio 2/3". If input PRIM is connected to L1 and L2, you should select "Ratio 1/3".

Attention: Input PRIM of the CT Analyzer has a low input impedance (330kΩ) and can thus influence the measurement results.

If it is possible to short-circuit the other windings on the same leg of the transformer, try to perform the measurement with this winding short-circuited. In this case, it is not necessary to use the delta compensation. Set delta compensation to "Ratio 1".

Refer to the following subsections.

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7.2.1 Ratio Measurement at a Delta Winding Transformer with Delta CompensationFor this measurement, the Delta compensation parameter on the CT-Object card has to be set to "Ratio 2/3".

Figure 7-2:Ratio measurement at a delta winding transformer with delta compensation

7.2.2 Ratio Measurement at a Delta Winding Transformer without Delta CompensationFor this measurement, the Delta compensation parameter on the CT-Object card has to be set to "Ratio 1".

Figure 7-3:Ratio measurement at a delta winding transformer without delta compensation

L2 L3

L1

L2 L3

L1


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7.3 Measurement at a Wye Winding TransformerMeasurement of CTs in wye connected transformer windings is indeed possible, however, it has to be guaranteed that the input impedance of the transformer winding does not influence the measurement result.

The CT Analyzer has an input impedance of approx. 330kΩ in low-voltage range. However, this can be low enough to influence the measurement result. In order to prevent any influence of the CT Analyzer’s input impedance, you have to short-circuit at least the winding on the same leg (short-circuiting a winding on all legs of the transformer is even better).

The current injection method is not suitable for the measurement of a current transformer inside a transformer, since the transformer windings are connected in series to the primary side of the CT. This is why the voltage injection method as it is used by the CT Analyzer is the only suitable method to perform such measurements.

When measuring a CT inside of such a configuration, input PRIM of the CT Analyzer has to be connected to both sides of the series connection consisting of the CT’s primary side and the particular transformer winding (refer to Figure 7-4, terminals L1 and N).

Connect the center point and, if possible, also the open primary terminals that are not connected to the CT Analyzer to protective earth.

Figure 7-4:Measurement at a wye winding transformer

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7.4 Measurement at a Bushing-Type CTProceed as follows to perform measurements at a bushing-type CT (refer to Figure 7-5):


2. Disconnect all utility lines from the transformer.

3. Connect all transformer terminals that are not used for measurement (in this example H2 and H3) to protective earth (PE).

4. Connect terminal H0 to protective earth.

5. Connect one secondary side terminal of the CT to protective earth.





8. Short-circuit the free winding on the measured transformer leg to reduce the impedance of the winding that is connected in series to the primary side of the CT. The input impedance of CT Analyzer input SEC is only approx. 500kΩ and can thus influence the measurement results, if no winding of that leg is short-circuited.

9. Start the test.


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Figure 7-5:Measurement at a bushing-type CT

Note: Primary terminal H1 must be open. Otherwise the primary side is shorted and the CT Analyzer cannot obtain proper results.

H0(Mp)(N)

H3(C)(W)

H2(B)(V)

H1(A)(U)

CT

Coax measurement cables

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7.5 Measurement at a GIS (SF6) Switch GearProceed as follows to perform measurements at a GIS (SF6) switch gear (refer to Figure 7-6):


2. Disconnect all utility lines.

3. Open all circuit breakers to the bus bars.

4. Close the earthing switch.

5. Connect one secondary side terminal of the CT to protective earth.





8. Start the test.


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Figure 7-6:Measurement at a GIS (SF6) switch gear Utility line

disconnected

max. 100m

Gas insulated busbar Earthing switch

Circuit breaker

max. 3m

Burden

Coax measurement cables

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7.6 Measurement on a Bar-Type Current TransformerWhen measuring on the primary side of the CT, it is not allowed to use large open measurement cable loops in order to avoid injection of interference voltages into the measurement cables caused by strong magnetic fields. Therefore, only the original coax measurement cables supplied by OMICRON or twisted-pair cables should be used for measurement instead of individual single wire measurement cables.

The measurement signals on the primary side are in the range of 1 to 30mV. Correspondingly, an injection of large interference signals into the measurement cables can cause faulty measurement results.

If one terminal of the bar-type current transformer can only be accessed from the neighboring room, one of the following methods has to be used in order to obtain exact ratio measurement results:

1. Feed one end of the coax measurement cable through a hole in the wall located in the immediate vicinity of the transformer’s terminal, near enough to use the original cable. If no such hole is available, it is recommended to drill a new hole into the wall.

2. If this is not possible:

• Connect the concerning primary terminal of the transformer located on the back side of the wall (in the neighboring room) to station ground as near as possible to the transformer (in Figure 7-7 designated with P2).

• Then, on the accessible front side of the wall,

– connect one pole of the primary measurement to station ground and the station ground to one socket of CT Analyzer input "PRIM", and

– connect the second socket of input "PRIM" to the second primary terminal of the CT located on the front side of the wall (in Figure 7-7 designated with P1).

Refer to Figure 7-7.


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Figure 7-7:Measurement at a bar-type current transformer

P2 P1

Wrong!Do not use open loops consisting of individual single-wire measurement cables!

Always use original OMICRON coax measurement cables or twisted-pair cables!

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7.7 Measurement on Tapped CTsWhen testing a tapped CT, all windings on the same core that are not in use must be open.

If one winding is not open, it is not possible to test the CT using the CT Analyzer.

The maximum output voltage of the CT Analyzer is 120V. Therefore, only the corresponding transformed voltage can occur at other windings.

Figure 7-8:Testing tapped CTs


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7.8 Measurement on a Gapped CoreFor gapped cores, the position of the primary wire inside the core has large influence to the ratio measurement results.

Therefore, in order to obtain correct measurement results, it is very important to arrange the primary wire during measurement to the same position inside the core as it is in real operation. Depending on the position of the primary wire inside the core, the measured ratio can differ by up to 20%.

The figure below shows how the ratio error can differ depending on the position of the primary wire inside the core.

Figure 7-9:Ratio error depending on the position of the primary wire inside the gapped core

Air gap

Position 2Ratio error measured: +5%

Position 1Ratio error measured: +0.5%

Position 3Ratio error measured: -15%

Primary wire

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7.9 Excitation Curve Measurement for an Unwound Iron CoreUsing the CT Analyzer it is possible to measure the excitation curve of an empty, unwound iron core. For this purpose, it is necessary to apply an "auxiliary winding" with approx. 30 turns to the core. The easiest method to do this, is to prepare a 30-pole cable accordingly with a plug on one side and a socket on the other side in order to create a "flying" winding with 30 turns by laying the cable around the core and connecting both sides of the cable by inserting the plug into the socket (see Figure 7-10).

Proceed as follows to perform the measurement (refer to Figure 7-10):


2. Apply the "auxiliary winding" with approx. 30 turns to the unwound core.

3. Connect the "Output" sockets and input "Sec" of the CT Analyzer to the auxiliary winding as shown in Figure 7-10. Twist the single-wire measurement cables to form twisted-pair lines as shown in Figure 7-10.

4. Start the test.Figure 7-10:Measuring the excitation curve of an unwound iron core

Note: Peak currents of up to 15 A can occur during the measurement. Therefore, the wires used for the "auxiliary winding" should have a minimum diameter of 0.75mm2.

Winding with approx. 30 turns applied for measurement

(0.75mm2 min.)

Twist the measurement cables to form a twisted-pair line

Unwound iron core

Plug-and-socket connector


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7.10 Measurement on Multicore CTsWhen performing tests on CTs with more than one core, you should shorten the windings of all cores that are not subject to the test in order to prevent measurement errors. Refer to Figure 7-11.

Figure 7-11:Measuring multicore CTs

7.11 Burden TestHow to connect the CT Analyzer for the burden test is described in section 3.1 ”Basic Wiring for a Burden Test” on page 25.

Do not shorten taps!

Shorten unused cores

Primary insulation

Primary conductor

Toroidal core

Secondary winding

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7.12 Noise Reduction TechniquesFor proper test results it is important to consider the following items:


• If possible, disconnect both primary terminals of the CT from the utility lines.

• Only use the original coax measurement cables delivered by OMICRON or twisted-pair lines. If it is necessary to use loose single-wire measurement cables, the wires have to be twisted to a twisted-pair line. Avoid open loops consisting of individual single-wire measurement cables in order to prevent interference voltages caused by magnetic fields.

• Connect one terminal of the CT’s primary side to protective earth. If it is not possible to disconnect the utility lines from both primary terminals, connect that side of the primary circuit that is able to receive more interferences to PE (the primary side that is still connected to the utility lines or the side with the longer line length, respectively). The ungrounded side should be the side that receives less interferences.

• When testing a CT in a utility, take care that one side of the CT is connected to PE and at least the ungrounded terminal is disconnected from all utility lines.

Refer to Figure 7-12.

Caution: Do not connect both primary terminals to PE! This would cause incorrect measurement results. Connecting both primary terminals to PE has the same effect as a short in the CT.


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Figure 7-12:Noise reduction for CT measurement Utility line Utility line

Connection required, if secondary side terminal cannot be disconnected

BurdenUse coax measurement cables!

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Calibrating the CT Analyzer

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8 Calibrating the CT AnalyzerOMICRON offers a reference CT (calibration CT VEHZ0649) for calibrating the CT Analyzer. This reference CT is delivered together with a calibration certificate of a national test laboratory.

The calibration CT has a ratio of 2000:1 and 2000:5. Its class is 0.02.

For calibrating the CT Analyzer, it is necessary to measure both ratios (2000:1 and 2000:5). The CT Analyzer is within the specifications, if all measurement results are within class 0.02.

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Error and Warning Messages

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9 Error and Warning Messages001.xxx Error [001] No valid CT software!

Reason: No valid software in the device Flash memory.Solution: Insert a Compact Flash card with valid software (CTAnalyzer.bin)

in the Omicron directory and switch the CT Analyzer off and on again.

002.xxx Error [002] Can't open file!Reason: The firmware cannot read the file CTAnalyzer.bin from the

Compact Flash card since the CF card or the file is missing.Solution: Insert a Compact Flash card with valid software (CTAnalyzer.bin)


003.xxx Error [003] Download error!Reason: The downloaded software is corrupt.Solution: Insert a Compact Flash card with valid software (CTAnalyzer.bin)


100.xxx Warning [100.xxx] Cannot determine valid winding resistance.Reason: The resistance measured during the winding resistance test is

> 300Ω.Solution: The test cannot be continued. Check the connections to the CT. If the

connections are ok, the CT resistance is > 300Ω. Such CTs cannot be tested using the CT Analyzer.

101.xxx Warning [101.xxx] Timeout during measurement. No constant winding resistance can be determined within 10 sec.Reason: The CT Analyzer cannot determine a constant winding resistance

within 10 sec.Solution: The test cannot be continued. Check the connections to the CT.

110.xxx Warning [110.xxx] The impedance of the CT is too high.Reason: The impedance of the CT or the load is too high to reach the minimum

toggle frequency of 1Hz.Solution: The test cannot be continued. Check the connections to the CT. If the

connections are ok, the CT cannot be tested due to its too high inductance.

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111.xxx Warning [111.xxx] Inductance of load too low.Reason: Measurement frequency is too high and cannot be decreased

because of too low CT inductance.Solution: The test cannot be continued. Check the connections to the CT. If the

connections are ok, investigate the following possible error causes:– The CT inductance is too low. The CT under test is a very small

CT with a knee point < 1V.– The CT has a winding short.– A bushing-type CT in a delta winding transformer possibly has too

low inductance due to the low impedance on the primary side that cannot be opened.

112.xxx Warning [112.xxx] Measurement error, check wiring.Reason: It is not possible to obtain stable measurement results due to

incorrect wiring, wiring short-circuit, connected load or external interferences.

Solution: Check the wiring. The primary side of the CT must not be short-circuited. Disconnect the primary side of the CT from the transmission lines, connect one primary side terminal to PE and open the other one. Use the delivered original coax cables for measurement (see application example in section 7.12 ”Noise Reduction Techniques” on page 158). Make sure that no burden is connected to the secondary side of the CT. This error may also indicate a winding short circuit of the CT.

113.xxx Warning [113.xxx] Test not successful, kneepoint not found.Reason: Knee point for specified standard not found.Solution: The current required to reach the knee point for the specified

standard cannot be delivered. The CT cannot be tested up to the knee point voltage.

114.xxx Warning [114.xxx] Low inductance overload in excitation measurement.Reason: Low inductance was measured during the excitation test.Solution: Verify that the primary side of the CT is not shorted.

This warning can also occur for CTs with very low excitation loss and high parasitic capacitance.

115.xxx Warning [115.xxx] Invalid eddy loss measurement.Reason: Reliable determination of the eddy losses is not possible.Solution: Verify the wiring and repeat the test. If the error message is displayed

repeatedly, it is currently not possible to test this CT using the CT Analyzer.


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121.xxx Warning [121.xxx] Wrong polarity.Reason: Measured polarity is wrong.Solution: Reverse the polarity of the measurement cables on the primary or

secondary side of the CT.

130.xxx Warning [130.xxx] Burden impedance > 1kOhm.Reason: Burden impedance > 1kΩ.Solution: The test cannot be continued. Check the connections to the CT.

131.xxx Warning [131.xxx] Overload during Burden measurement.Reason: The required test current cannot be reached, even at the maximum

output voltage.Solution: The CT Analyzer cannot deliver enough current. Reduce the test

current or the impedance of the burden. Check the wiring for proper contacts; one connection possibly has a bad connection.

200.xxx Warning [200.xxx] Check connection. Measured input voltage and output voltage don’t match.Reason: The measured input voltage differs by more than 5V from the input

voltage expected during burden test.Solution: Check whether the output generator ("Output") and the measurement

input "Sec" are connected correctly.

201.xxx Warning [201.xxx] Check connection. Measured ratio > 50000:1.Reason: Measurement input "Prim" is possibly not connected properly.Solution: Check whether the primary side measurement input "Prim" is

connected properly.

202.xxx Warning [202.xxx] Check connection. Polarity of Vsec input and power output are not the same.Reason: Polarity of input "Sec" and "Output" are not the same.Solution: Check whether the output generator ("Output") and the measurement

input "Sec" are connected properly and with correct polarity.

203.xxx Warning [203.xxx] Check connection. Vsec input may be disconnected.Reason: Input signal at input "Sec" differs from the expected one.Solution: Check whether the output generator ("Output") and the measurement

input "Sec" are connected properly and with correct polarity.Check if the impedance of the test leads from the output to the CT is < 0.6Ω. Use the 3m standard measurement cable supplied by OMICRON for measurement.

210.xxx Warning [210.xxx] Permanent data overflow.Reason: Internal data buffer overflow. The data could not be fetched fast

enough from the internal data buffer.Solution: Try to repeat the measurement. If this error occurs more frequently,

you should contact your next OMICRON service center.

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211.xxx Warning [211.xxx] AC mode measurement timeout.Reason: Measurement timeout due to frequent range switching or invalid data

from the measurement inputs.Solution: Check the wiring and repeat the measurement. Try to reduce noise

for the measurement.

220.xxx Warning [220.xxx] Test aborted!Reason: The test sequence has been interrupted by the user.Solution: Repeat the test without interrupting it.

501.xxx Warning [501.xxx] Unknown CommandReason: The remote interface handler couldn't decipher the command.Solution: Remote interface error. Check the connection between CT Analyzer

and PC.

504.xxx Warning [504.xxx] Checksum errorReason: Data transmission error.Solution: Check the connection between CT Analyzer and PC.

510.xxx Warning [510.xxx] No data available.Reason: Remote interface error: Failed to get the required measurement data

because the measurement is still running.Solution: Check the connection between CT Analyzer and PC.

511.xxx Warning [511.xxx] Data compression errorReason: Remote interface error: Failed to unzip the transmitted data block.Solution: Check the connection between CT Analyzer and PC.

513.xxx Warning [513.xxx] Command not allowedReason: The current remote interface command is not allowed.Solution: Make sure that the current CT Analyzer state allows the execution of

the command.

514.xxx Warning [514.xxx] Invalid parameterReason: Remote interface error: Remote command was submitted with an

invalid parameter.Solution: Verify the parameter (index) submitted with the remote interface

command.

800.xxx Warning [800.xxx] Flash card access error. Internal file system error.Reason: The file system sent an error message.Solution: Compact Flash card is possibly corrupt. Use a new Compact Flash

card.

801.xxx Warning [801.xxx] Flash card access error. Invalid file name or path.Reason: The file system sent an error message.Solution: The Compact Flash card is possibly corrupt. Try to save the data to

a PC and format the CF card.


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802.xxx Warning [802.xxx] Flash card access error. Access denied.Reason: The file system sent an error message. You tried to open a "read

only" file or a special directory.Solution: Open the Compact Flash card on a PC and remove the "read-only"

file attribute. File attributes cannot be changed with the CT Analyzer.

803.xxx Warning [803.xxx] Flash card access error. File or folder already exists.Reason: File system error.Solution: Enter a different file or folder name.

804.xxx Warning [804.xxx] Flash card access error. Disk full.Reason: The file system sent an error message.Solution: Delete some files on the Compact Flash card or insert a new CF card.

805.xxx Warning [805.xxx] Flash card access error. No or corrupt flash card.Reason: No or no valid CF card can be found.Solution: Insert a valid Compact Flash card.

806.xxx Warning [806.xxx] Flash card access error. Corrupt directory structure.Reason: The file system sent an error message.Solution: Try to backup the data on the Compact Flash card to a PC and

perform formatting of the Compact Flash card.

807.xxx Warning [807.xxx] Nothing to paste.Reason: No file(s) selected to paste.Solution: Select one or more files using the C O P Y or C U T function and try

again.

808.xxx Warning [808.xxx] Renaming of folders not supported.Reason: This action is not supported.Solution: Renaming of folders is not supported by the CT Analyzer.

809.xxx Warning [809.xxx] Are you sure you want to format the CF card? All data will be lost!Reason: This warning always appears before formatting of a Compact Flash

card is executed, since all data stored on the Compact Flash card will be erased during formatting.

Solution: Press F O R M A T to start formatting or A B O R T to cancel the operation without formatting the Compact Flash card.

810.xxx Warning [810.xxx] File exists. Do you want to overwrite it?Reason: The file name used to save the data already exists. This warning

always appears before a file on the Compact Flash card is overwritten.

Solution: Enter another file name, if desired.

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811.xxx Warning [811.xxx] Are you sure you want to delete <File Name>?Reason: This warning always appears prior to the deletion of a file on the

Compact Flash card.Solution: Press Y E S to delete the file or N O to return to the file system card

without deleting the file.

812.xxx Warning [812.xxx] Are you sure you want to delete all selected files?Reason: This warning always appears prior to the deletion of files on the

Compact Flash card.Solution: Press Y E S to delete the files or N O to return to the file system card

without deleting the files.

813.xxx Warning [813.xxx] One or more parameters could not be found. Some calculations may not work.Reason: The report file read from the Compact Flash card is of a newer format

than the device can generate. Solution: The loaded file is incompatible or the software version on your

CT Analyzer is older than the software version that has generated the report. To enable your CT Analyzer to read this report, it is necessary to update the CT Analyzer software.

814.xxx Warning [814.xxx] You tried to load an old report. One or more parameters could not be found. Some calculations may not work.Reason: A required parameter cannot be found in the XML file.Solution: You tried to load an old report. One or more parameters could not be

found. Some calculations may not work.

815.xxx Error [815.xxx] Folder must be empty. Can't remove folder <Folder Name>.Reason: The folder selected for deletion is not empty. Only empty folders can

be deleted.Solution: Navigate to the folder you want to delete. Open the folder and delete

all contained files and subfolders. Then you can delete the empty folder.

816.xxx Error [816.xxx] You tried to load a report built with a <Device>.Reason: The xml file seems to be not a CT Analyzer report.Solution: The report cannot be loaded by the CT Analyzer.

817.xxx Error [817.xxx] Xml file is not an OMICRON report.Reason: The xml file has no valid OMICRON report style.Solution: The report cannot be loaded by the CT Analyzer.

818.xxx Error [818.xxx] Moving of folders not supported.Reason: Moving of folders is not supported by the CT Analyzer.Solution: Select only files to move. Using the shift key and the cursor up/down

keys it is possible to select any number of files within a folder.


169

819.xxx Error [819.xxx] Invalid file name character.Reason: An invalid character was used to specify the file name.

Invalid characters: \ / : * ? \ < > |Solution: Only use valid characters for the file name.

820.xxx Error [820.xxx] Memory management error. Contact your next OMICRON service center.Reason: Memory management error.Solution: Switch the CT Analyzer off, wait a second then switch it on again. If

this error occurs more frequently, you should contact your next OMICRON service center.

821.xxx Error [821.xxx] Could not update firmware.Reason: An error has occurred in the boot loader software.Solution: Insert a Compact Flash card with valid software (CTAnalyzer.bin)

in the directory A:\Omicron\ and switch the CT Analyzer off and on again.

823.xxx Error [823.xxx] Could not update user text!Reason: An error has occurred in the user text loader software.Solution: Insert a Compact Flash card with valid software (CTUser_xxx.bin)

in the directory A:\Omicron\ and try again.

824.xxx Error [824.xxx] Floating point error at address xxxxxxxH.Reason: Invalid result in a floating point operation (NaN).Solution: Contact your next OMICRON service center.

830.xxx Error [830.xxx] License < ... > invalid.Reason: An invalid license entry was found in the license file Omicron.lic

on the CF Card.Solution: Specify a valid license key.

831.xxx Error [831.xxx] Settings error.Reason: Invalid item in file Settings.inf.Solution: The file Settings.inf in the Omicron directory on the CF card of

the CT Analyzer has a formatting error in one of the parameters. Delete this file and check the settings in the menu "Main Menu -> Settings-> Misc. Settings". If necessary, change the settings and store the file again.

832.xxx Error [832.xxx] Lifetime of relays near end.Reason: The relays inside the CT Analyzer near the end of their lifetime

(above 1,000,000 measurements performed).Solution: Arrange a hardware service in order to replace the relays.

CT Analyzer

170

900.xxx Error [900.xxx] Power supply error, switch off the device and wait 1 minute to restart.Reason: The output power was larger than 350VA or the power supply is

defective.Solution: Switch the CT Analyzer off, wait 1 minute and then switch it on again.

If this error occurs more frequently, you should contact your next OMICRON service center.

901.xxx Warning [901.xxx] Protective earth (PE) connection in power supply cord missing. Connect PE to equipotential terminal. Lethal voltage may occur on housing and all terminals.Reason: Earth wire break, no earth wire connected or mains supply has no

galvanic connection to protective earth (PE) potential.Solution: The mains supply has not reference to protective earth or protective

earth is not connected. The mains supply must have galvanic connection to PE. If you are using an isolation transformer, connect one supply line of the CT Analyzer to PE.Danger: Lethal voltages may occur at the housing if the equipotential bonding terminal of the device is not connected to protective earth potential! Attention: If the mains supply is galvanically isolated from earth potential, the device may become damaged.

Comment: If a galvanically isolated mains supply is used, voltage stress may occur for the insulation system, the device is not constructed for. Safety is no longer guranteed! Therefore, always use a mains power cord with a protective earthing conductor connected to PE of the mains supply. Connect the equipotential bonding connection of the device to protective earth in order to prevent electric shock caused by lethal voltages possibly present at the housing. If this error is ignored, the device will probably work but safety is no longer guaranteed.

903.xxx Warning [903.xxx] Excessive reverse power, don't disconnect any wires, don't switch off mains, wait until power is dissipated.ATTENTION: Lethal voltages on output terminals!Reason: The device receives excessive reverse power so that the power

output had to be shortened to prevent overload of the internal output stage.

Solution: This error is displayed if an excess amount of energy is fed back into the CT Analyzer. Lethal voltages of up to many kV may occur if wires are unplugged. The CT Analyzer discharges the connected inductor with approximately 20Ws, but depending on the connected inductance the discharge process may take some time.


171

904.xxx Error [904.xxx] Power supply error. Contact next Omicron service center.Reason: Temperature limit of secondary power supply exceeded.Solution: It is not possible to acknowledge this error until the temperature is

back in safe limits. It this error occurs, please contact your next OMICRON service center.

905.xxx Error [905.xxx] Over-temperature of Power supply, wait until device has cooled down.Reason: Overtemperature in power supply. Wait until device has cooled down.Solution: When this error is acknowledged as long it is active, the popup

window is closed and only the message in the status line remains active until the overtemperature disappears. If the error is not acknowledged, the popup window remains active.

Comment: The status line displays the flashing message "Excess temperature".

906.xxx Error [906.xxx] Excess temperature of power supply, wait until device has cooled down.Reason: The primary side power supply has reached its warning temperature

limit and entered save mode to cool down.Solution: When this error is acknowledged as long it is active, the popup

window is closed and only the message in the status line remains active until the overtemperature disappears. If the error is not acknowledged, the popup window remains active.

Comment: The status line displays the flashing message "Excess temperature".

908.xxx Error [908.xxx] Device shut down.Reason: Power failure at measurement interface module.Solution: Internal power failure. This message is active as long as the internal

power failure exists. If the error message does not disappear, contact your next OMICRON service center.

910.xxx Error [910.xxx] Internal hardware error.Reason: Internal hardware error.Solution: Overload on internal power stage. Try to start the measurement

again.

911.xxx Error [911.xxx] Power supply error, contact next Omicron service center. Desired voltage xxxx, measured voltage yyyy.Reason: One supply voltage on the measurement interface boards is out of

tolerance.Solution: Contact your next OMICRON service center.

CT Analyzer

172

912.xxx Error [912.xxx] Excess internal temperature, wait until device has cooled down.Reason: Device-internal temperature at measurement interface > 75°C.Solution: Excessive heating of the device. Prevent the device from direct

sunlight and wait until it has cooled down. If the error occurs without previous exposure to direct sunlight, the error is probably caused by a hardware error. Please contact your next OMICRON service center.

Safety action:All measurement processes are stopped and the error is displayed in the status line and in a popup window. The error is active until the temperature falls below 60°C.

929.xxx Error [929.xxx] Hardware failure, contact next Omicron service center.Reason: The circuit for reverse power dissipation does not work properly.Solution: Contact your next OMICRON service center.

930.xxx Error [930.xxx] Measurement Input Vsec defect, contact next Omicron service center.Reason: Power supply for analog input "Sec" is defective.Solution: Contact your next OMICRON service center.

931.xxx Error [931.xxx] Measurement Input Vprim defect, contact next Omicron service center.Reason: Power supply for analog input "Prim" is defective.Solution: Contact your next OMICRON service center.

932.xxx Error [932.xxx] Data error.Reason: The sequence of reading of the analog input channels is not correct.Solution: If this error occurs more frequently, contact your next OMICRON

service center.

933.xxx Error [933.xxx] Hardware failure, contact next Omicron service center.Reason: Temperature detection circuit on secondary side is defective.Solution: Send the device to your next OMICRON service center.

934.xxx Error [934.xxx] Reverse power, don't disconnect any wires, don't switch off mains, wait until power is dissipated. I = xxxxA.Reason: The device receives reverse power of > 10mA.Solution: Wait until the power is dissipated within the device and the error

message disappears.

935.xxx Error [935.xxx] No valid CT Analyzer software. Insert a CF-Card with valid Software and press "Update Firmw.".Reason: Cannot find valid CT Analyzer software.Solution: Insert a Compact Flash card with valid software (CTAnalyzer.bin)

in the directory A:\Omicron.


173

936.xxx Error [936.xxx] Corrupt Calibration Data for voltage inputs. Change to tools menu and try to reset factory calibration. Until update of calibration data the device will be not calibrated.Reason: The calibration data checksum for the analog inputs is not correct.Solution: Try to update the factory calibration using the tools menu. If this does

not solve the problem, contact your next OMICRON service center.

937.xxx Error [937.xxx] Corrupt Calibration Data for power output. Change to tools menu and try to update factory calibration. Until update of calibration data the device will be not calibrated.Reason: The calibration data checksum for the power output is not correct.Solution: Try to update the factory calibration using the tools menu. If this does

not solve the problem, contact your next OMICRON service center.

938.xxx Warning [938.xxx] MIF data block 1 corrupt.Reason: The checksum of the factory settings data is faulty.Solution: Licensing or device settings data are possibly corrupt. Contact your

next OMICRON service center.

939.xxx Warning [939.xxx] MIF data block 2 corrupt.Reason: The checksum of the factory settings data is faulty.Solution: Licensing or device settings data are possibly corrupt. Contact your

next OMICRON service center.

940.xxx Warning [940.xxx] CMOS data block corrupt. Check all device settings. Press <Clear Values> to work with default values. Press <OK> to work with corrupt device settings.Reason: Device settings data block corrupt.Solution: Check all device settings.

941.xxx Warning [941.xxx] Corrupt factory calibration data for voltage inputs. Contact next Omicron service center.Reason: Factory calibration data block for voltage inputs corrupt.Solution: Contact your next OMICRON service center.

942.xxx Warning [942.xxx] Corrupt factory calibration data for power unit. Contact next Omicron service center.Reason: Factory calibration data corrupt.Solution: Contact your next OMICRON service center.

943.xxx Error [943.xxx] Error overwriting calibration data.Reason: Factory calibration data cannot be restored.Solution: Contact your next OMICRON service center.

CT Analyzer

174

944.xxx Warning [944.xxx] Corrupt user text! Change to tools menu and try to update text. Until update of user text, the device will use default text.Reason: Checksum for user language support data invalid.Solution: Copy a user text file (CTUser_xxx.bin) to the directory

A:\Omicron\ on the Compact Flash card and try to update the user language support data using the "Update Text" function in the tools menu.

Formulas and Definitions

175

10 Formulas and Definitions

10.1 Calculation of Ratio Error (Current Ratio)Figure 10-1:Equivalent circuit of a current transformer

Figure 10-2:Phasor diagram of a current transformer

Iex total excitation currentICT current over the secondary terminalsIST total secondary current

Ip primary current

Lp leakage inductance of the primary winding (negligible)Lmain main inductanceLs leakage inductance of the secondary winding (negligible)Np, Ns turns of the ideal transformer

N turns ratio

Rct resistance of the secondary windingReddy eddy-current resistanceRH hysteresis resistanceRp resistance of the primary winding (negligible)UC (VC) secondary excitation voltage on the main inductance (Lmain)

N N

U

L RCT

Z

S1

S2

I

Reddy

L

Lmain

R

IL

IE

RH

P1

P2

UCT

(VB)

s

ex

c

sp

pp

b

ICTIp

(V )c

IST

VC VB

ICTIex

ISTIex

RCTICTϑβ

γδ

ϕ

IpNsNp------ Iex ICT+( )⋅=

NturnsNsNp------=

CT Analyzer

176

UCT (VB) voltage at the secondary terminalsZB burdenZload total load impedance (ZB + RCT)

The calculation of the ratio error is based on the excitation table. With a given excitation voltage VC, the excitation table allows to find the corresponding excitation current Iex and the phase between Iex and VC. Since the ratio error is defined by the primary current Ip and the secondary load current ICT, the excitation table can be used to determine the value of ICT that corresponds to the given VC for a particular core. Provided that the rated turns ratio Nrated and the turns ratio Nturns are known, the ratio error calculation for the given primary current Ip and the burden impedance ZB,ϕ is as follows ( is always a reference pointer):

1. Calculate the real and imaginary parts of the burden impedance:

2. Calculate the total load impedance:

3. Given desired total secondary current ICT.

4. Calculate the secondary excitation voltage by

5. Look up the excitation current corresponding to this voltage and the phase ϑ between them in the excitation table:

6. Calculate the phase between the secondary load current and the excitation current:

7. Calculate the total secondary current:

SIr

RB ZB ϕcos⋅= XB ZB ϕsin⋅=

Zload ; Rload RCT RB+= ; Xload XB= ; Zload Rload2 Xload

2+=

γ arg Zload( )= arctanXloadRload-------------⎝ ⎠⎛ ⎞=

VC ICT Zload⋅=

Iex VC⇔ ; ϑ IE∠ VS,=

β ϑ γ–=

IST ICT Iex+= ; IST ICT Iex βcos⋅+( )2 Iex βsin⋅( )2+=


177

8. Calculate the primary current:

9. Calculate the ratio (current) error:

10.Calculate the phase displacement as the phase between and :

10.2 Turns Ratio ErrorTurns ratio error calculation according to IEC 60044-1, §2.3.14:

Ip IST Nturns⋅=

Errratio

ICTIp

Nrated---------------–⎝ ⎠

⎛ ⎞

IpNrated---------------

-----------------------------------=

STIr

CTIr

δ arg IST( )= arctanIex βsin⋅

ICT Iex βcos⋅+--------------------------------------⎝ ⎠⎛ ⎞=

Turns ratio error (%)Nmeasured Ipn Isn⁄( )–

Ipn Isn⁄( )----------------------------------------------------- 100⋅=

CT Analyzer

178

10.3 Calculation of RCF for IEEE C57.13According to IEEE C57.13, §3.32, RCF is defined as follows:

"The ratio of the true ratio to the marked ratio. The primary current or voltage is equal to the secondary current or voltage multiplied by the marked ratio times the ratio correction factor".

The CT Analyzer calculates it as follows:

RCF ratio correction factor

Ip primary rms current

Is secondary rms current

K Ipn/Isn (nominal primary current / nominal secondary current)

10.4 Calculation of e.m.f. rms Voltage (Uc)The following formula is used to calculate the e.m.f rms voltage (UC), if voltage is applied at the secondary terminal (refer to Figure 10-1 page 175):

RCFIpIs K⋅------------=

∫ −=t

ctctctc dtiRUfU0

)(*2

2π


179

10.5 Calculation of Instrument Security Factor (FS)According to IEC 60044-1 the instrument security factor is the ratio of the rated instrument limit primary current to the rated primary current. The rated instrument limit primary current is defined as that minimum primary current at which the composite error of the CT is equal to or greater than 10%.

The standard delivers two methods to calculate FS:

• The indirect method for calculating the FS (refer to section 10.5.2 on page 181).

• The direct method as described in appendix A of the standard (refer to section 10.5.1).

The CT Analyzer supports both methods, the calculation according to the direct method as well as the calculation according to the indirect method.

10.5.1 Calculation of Instrument Security Factor (FS) according to the Direct Measurement MethodThe direct method considers the ratio error of the CT and is therefore more accurate than the indirect method. The direct method is implemented as follows:

For calculation of FS, the measured secondary winding resistance is corrected to 75°C. The device calculates the FS for the nominal burden and the operating burden.

Calculation of the composite current Ic is performed as follows, according to the equation a2 = b2 + c2 - 2 b c cosα.

Is (b)

αIp / N (c)

Ic (a)

CT Analyzer

180

Isn rated secondary current

Iexc excitation current


Ic calculated composite current

Ipn nominal primary current


Ipsc rated primary short curcuit current

FS instrument security factor

N rated transformer winding ratio

εc Composite error

Note 1: The composite current cannot be compared to the excitation current in the excitation graph, since the composite current is calculated with Rct at 75°C and the excitation current is measured at ambient temperature. Furthermore, the winding compensation is included in the value of the used secondary current Is. In order to verify the calculated value, use the following formula to calculate the excitation current:

The excitation current now delivers an according value on the excitation curve that can be used to calculate the burden current.

Note 2: The output current is not measured, but calculated instead. Therefore, the accuracy of FS can differ by up to 10% from the reality.

Ic Is2 Ip

N----⎝ ⎠⎛ ⎞

22 Is

IpN---- αcos⋅ ⋅ ⋅⎝ ⎠

⎛ ⎞–+=

FSIpscIpn---------=

IpN----

εcIc

IpnN

------- FS⋅------------------- 100⋅=

at that point where the composite current is 10 % of

IextIpn FS⋅N

------------------ 0.1⋅=


181

10.5.2 Calculation of Instrument Security Factor (FSi) according to the Indirect Measurement MethodThe calculation of FSi according to the IEC 60044-1 indirect measurement method is implemented as follows:

1. Calculation of the total impedance under consideration of the phase of the load (burden).

2. Stepping up the current through the load (Z) (CT output current) until the excitation current reaches 10% of the current flowing through the load (Z)

( ).

For each step, the calculation has to be done to read the corresponding Iext from the excitation graph.

Attention: The e.m.f. voltage has to be used to find out Iext for the calculation of FSi as defined in the standard IEC 60044-1. Do not use the terminal voltage to find the corresponding Iext, since this would lead to incorrect results. Because the standard excitation graph according to IEC 60044-1 only shows the terminal voltage, you should switch to the ANSI excitation graph on the CT Analyzer. With the tools CTA Remote Excel File Loader or CTA Remote Control it is possible to get the e.m.f. values from the excitation graph.

3. After the point where the excitation current is 10% of the output current is found, the FSi can be calculated as follows:

The result is displayed as FSi in the user interface and in all reports.

Z Rburden RCT_75°+( )2 Xb2+=

Rburden Zburden ϕcos⋅=

Xb Zburden 1 ϕ2cos–⋅=

IextIout-------- 0.1=

Vemf Iout Z⋅=

FSiIoutIsn--------=

CT Analyzer

182

10.5.3 Example for Verification of FSiRefer to the CT Analyzer test cards shown below.

• Nominal load = 10VA, cosϕ = 0.8

• I-sn = 1A

• Rct at 75°C = 3.907Ω

• FSi = 6.16

• FS = 10Figure 10-3:Values determined by the CT Analyzer

Proceed as follows to verify the FSi value:

1. Calculate the total impedance of the CT incl. the winding resistance Rct:

2. Calculate Vemf as follows: Vemf = FSi * Isn * Z

Z 10 ϕcos 3.907+⋅( )2 10 1 ϕcos 2–⋅( )2

+ => 13.33 Ω=

Vemf FSi Isn Z⋅ ⋅=

Vemf 6.16 1 13.33⋅ ⋅=

Vemf 82.1 V=


183

3. Read Iext from the ANSI excitation graph at Vemf (e.g. at 82 V: Iext = 0.588 A).

4. Calculate whether FSi is really at the 10% error border:

Or calculate the error at FSi:

5. FSi must be lower than the FS on the CT-Object card (FSi ≤ FSrated):

5.88 < 10 = true => ok

Attention: Often it is not possible to read the point where the CT reaches an error of 10% on the excitation graph because the excitation graph is not measured far enough. In this case, use the highest available point to verify FSi.

FSiIext 10⋅Isn

------------------= 0.588 A 10⋅1 A

-----------------------------= => FSi 5.88∼

Error [%]Iext

FSi Isn⋅-------------------- 100⋅= => Error 9 5 %,∼= 0.588

6.16 1⋅------------------ 100⋅

CT Analyzer

184

10.6 Calculation of Accuracy Limiting Factor (ALF)According to IEC 60044-1 the accuracy limiting factor is the ratio of the rated accuracy limit primary current to the rated primary current. Depending on the accuracy class, the accuracy limiting factor is defined as that primary current at which the composite error is equal to or smaller than 5 % or 10 %.

The standard delivers two methods to calculate ALF:

• The indirect method for calculating the ALF (refer to section 10.6.2 on page 186).

• The direct method as described in appendix A of the standard (refer to section 10.6.1).

The CT Analyzer supports both methods, the calculation according to the direct method as well as the calculation according to the indirect method.

10.6.1 Calculation of Accuracy Limiting Factor (ALF) according to the Direct Measurement MethodThe direct method considers the ratio error of the CT and is therefore more accurate than the indirect method. The direct method is implemented as follows:

For calculation of ALF, the measured secondary winding resistance is corrected to 75°C. The device calculates the ALF for the nominal burden and the operating burden.

Calculation of the composite current Ic is performed as follows, according to the equation a2 = b2 + c2 - 2 b c cosα.

Is (b)

αIp / N (c)

Ic (a)


185


Iexc excitation current


Ic calculated composite current

Ipn nominal primary current


Ipsc rated primary short curcuit current

ALF accuracy limiting factor

N rated transformer winding ratio

εc Composite error

Note 1: The composite current cannot be compared to the excitation current in the excitation graph, since the composite current is calculated with Rct at 75°C and the excitation current is measured at ambient temperature. Furthermore, the winding compensation is included in the value of the used secondary current Is. In order to verify the calculated value, use the following formula to calculate the excitation current:

The excitation current now delivers an according value on the excitation curve that can be used to calculate the burden current.

Note 2: The output current is not measured, but calculated instead. Therefore, the accuracy of ALF can differ by up to 10% from the reality.

Ic Is2 Ip

N----⎝ ⎠⎛ ⎞

22 Is

IpN---- αcos⋅ ⋅ ⋅⎝ ⎠

⎛ ⎞–+=

ALFIpscIpn---------=

IpN----

εcIc

IpnN

------- ALF⋅----------------------- 100⋅=

at that point where the composite current is 5 % or 10 % of

IextIpn ALF⋅

N----------------------- 0.1⋅= for a 5 % CT, use factor 0.05 instead of 0.1

CT Analyzer

186

10.6.2 Calculation of Accuracy Limiting Factor (ALFi) according to the Indirect Measurement MethodThe calculation of ALFi according to the IEC 60044-1 indirect measurement method is implemented as follows:

1. Calculation of the total impedance under consideration of the phase of the load.

2. Determination of the excitation current where with

3. Reading of the e.m.f. voltage (Val) from the excitation cuve (e.m.f. voltage that corresponds to the excitation current determined in step 2.).

Attention: The e.m.f. voltage has to be used to find out Iext for the calculation of ALFi as defined in the standard IEC 60044-1. Do not use the terminal voltage to find the corresponding Iext, since this would lead to incorrect results. Because the standard excitation graph according to IEC 60044-1 only shows the terminal voltage, you should switch to the ANSI excitation graph on the CT Analyzer. With the tools CTA Remote Excel File Loader or CTA Remote Control it is possible to get the e.m.f. values from the excitation graph.

4. Calculation of ALF:

The result is displayed as ALFi in the user interface and in all reports.

The ALFi can be verified using the following equation:

Val is the voltage where (10% error current).

Z Rburden RCT_75°+( )2 Xb2+=

Rburden Zburden ϕcos⋅=

Xb Zburden 1 ϕ2cos–⋅=

IextIout-------- 10⋅ 1= Iout

VemfZ

-----------=

ALFValZ Isn⋅--------------=

ALF Isn⋅ValZ

-------≥

IextIout-------- 10⋅ 1=


187

10.7 Calculation of Peak Instantaneous Error (ε^)CT Analyzer calculates ε^ according to IEC 60044-6, §3.3:

ε^

Iext Peak excitation current read from the excitation graph at Emax.

Emax

Ktd meas Ktd calculated (parameter from Excitation card), refer to section 10.17 ”Determination of Transient Dimensioning Factor (Ktd)” on page 196.

Kssc Kssc from the settings (CT-Object card).

RCT Measured winding resistance (RCT) at 75°C.

Rb Burden entered in CT-Object card for parameter "VA" or "Burden", depending on the selected page on the Excitation card (using the soft key R E S U L T W I T H N O M. V A or R E S U L T W I T H B U R D E N).

10.8 Calculation of Rated Symmetrical Short Circuit Current Factor (Kssc)The calculation of the symmetrical short-circuit current current factor is done according to IEC 60044-6, §3.15:

ε 100 Iext⋅2 Isn Kssc⋅ ⋅

--------------------------------=

Emax Kdt_meas Kssc Isn RCT Rb+( )2 Xb2+⋅( )⋅ ⋅=

KsscIpscIpn---------=

CT Analyzer

188

10.9 Calculation of Dimensioning Factor (Kx)The dimensioning factor Kx is only used for IEC 60044-1 class PX.

Ek rated knee point e.m.f.

Rb rated resistive burden

Rct resistance of secondary winding at 75°C


On the Excitation card, Kx is calculated at the Iprim where the accuracy limit (Ek) is reached with the selected load. The selected load can be the nominal burden (parameter "VA", soft key R E S U L T W I T H N O M. V A ) or the operating burden (parameter "Burden", soft key R E S U L T W I T H B U R D E N).

10.10 Calculation of Secondary Loop Time Constant (Ts)Value of the time constant of the secondary loop of the current transformer obtained from the sum of CT inductance and resistance and secondary loop inductance and resistance.

Ls sum of magnetizing and leakage inductances

Lct unsaturated inductance of the CT

Lb inductance of the measured burden

Rs secondary loop resistance

Rct CT resistance at 75°C

Rb resistive portion of measured burden without temperature correction

KxEk

Rct Rb+( ) Isn⋅-----------------------------------=

s

sS R

LT = RS = Rb + Rct75°C Rb = Rwire + Rrelay LS = Lct + Lb


189

10.11 Calculation of Rated Secondary Terminal Voltage (VB) acc. to IEEE C57.13The rated secondary terminal voltage is calculated at the point where the current ratio error is 10%. We defined this error as follows:

In other words, Iprim is the primary current where the CT has an error of 10%.

Then, the rated secondary terminal voltage can be calculated as follows:

Furthermore, the secondary excitation voltage VC can then be calculated as follows:

To understand the formulas please refer to the equivalent circuit for current transformer (refer to section 10.1 on page 175).


Ipn rated primary current

Iprim primary AC current

VC, UC secondary excitation voltage at main inductance (Lmain)

Rct resistance of secondary winding

Zb external impedance at rated frequency

Rb resistive part of burden

Xb reactance of burden

UCT, VB voltage at secondary terminal

ICT current at the secondary terminals

Iprim ICT ratio×( )–( ) 10× 0=

VB ICT Zb×=

Vc ICT Xb2 Rb Rct+( )2+×=

CT Analyzer

190

10.12 Remanence Factor (Kr)

Used measurement methodAn AC method very similar to the definition in IEC 60044-6, annex B2, is used.

The CT Analyzer measures the flux in the main inductivity and not at the terminals. This is possible because the CT Analyzer subtracts the voltage over the winding resistance Rct from the voltage measured at the terminals (Uc = Uct – (Rct x Ict)).

Measuring the flux in the main inductivity (i.e., behind the winding resistor) delivers the same result as measuring the flux on a second transformer winding with the same number of turns. In other words, the CT Analyzer measures the hysteresis loop in the core and therefore measures that flux that is really of interest.

It is not necessary for the CT Analyzer to wait 3 minutes after the test is finished (as described in IEC 60044-6, § 3.25) because no burden is connected to the CT during the test and therefore the current almost immediately returns to zero after the deactivation of the voltage at the terminals. In a real CT, the current only decreases with the secondary time constant (L/R) and thus can require up to 3 minutes until it is actually zero.

Saturation flux (Ψs)That peak value of the flux which would exist in a core in the transition from the non-saturated to the fully saturated condition and deemed to be that point on the B-H characteristic for the core concerned at which a 10 % increase in B causes H to be increased by 50 %

Remanence factor (Kr):

Ψr = remanent flux

Ψs = saturation flux

Kr = remanence factor in %

s

rrK Ψ

Ψ= *100

Magnetizingforce

Remanence

Coercivity

B

H

Ψr

Ψs


191

Remanent flux (Ψr)That value of flux which would remain in the core 3 min after the interruption of an exciting current of sufficient magnitude to induce the saturation flux (Ψs).

10.13 Saturated Inductance (LS)The following steps are used to determine the saturated inductance.

1. Calculation of inductance of the two most top measurement points:

Ψ = measured flux

I = peak current at measurement point

Point 1 is the highest measured point of the IEC 60044-6 excitation curve, and point 2 is the second highest point of the same curve.

2. Calculation of inductance between points 2 and 3:

Point 2 is the second highest measured point of the IEC 60044-6 excitation curve and point 3 is the third highest point of the same curve.

3. Calculation of inductance between points 1 and 3:

4. If one of the following conditions applies, the saturated inductance cannot be determined and n/a will be shown as result:

Iknee = knee-point current according to IEC 60044-6

1,05

1

0,95

0,9

0,85

0,8

0 2 4 6 8

12

3

Ipeak [A]

Flux

[Vs]

21

2112 IIL

−Ψ−Ψ=

32

3223 IIL

−Ψ−Ψ=

31

3113 IIL

−Ψ−Ψ= = sL

5.15.023

12 <<LL

mHL 3013 >

(2)

(3)

kneeknee IIANDAI 51 1 << (1)

CT Analyzer

192

10.14 Non-saturated Inductance (Lm)The non-saturated inductance is calculated as the mean inductance within the linear region of the excitation curve in the range between 20% and 90% of the knee point. If the curve is reaching the non-linear zone at a value smaller than 90% of the knee point, the last point before the curve reaches the non-linear zone is taken as the uppermost measurement point. The zone between 20% and 90% (or the uppermost point) is linearly divided into 10 segments and the non-saturated inductance is calculated as the arithmetic mean value of these 10 segments.

One point is calculated as follows:

Ψn, In = peak flux and peak current at one point of the excitation curve

The total unsaturated inductance is calculated as follows:

10.15 Knee PointAccording to IEC 60044-1The point on the excitation graph (Vkn, Ikn) where an increase of the secondary terminal rms voltage by 10% causes a 50% increase of the rms current into the secondary terminals.

According to IEC 60044-6The point on the excitation graph (Vkn, Ikn) where an increase of the emf rms voltage (core flux) by 10% causes an increase of the peak current by 50%.

According to IEEE C57.13-1993 (ANSI)

LnΨnIn-------=

Lm

LnL20%

L90%

∑n

---------------------=


193

For current transformers with non-gapped cores, the knee is defined as the point (Vkn, Ikn) where the tangent is at 45 degrees to the abscissa. For current transformers with gapped cores, the knee is defined as the point where the tangent is at 30 degrees to the abscissa.

10.16 Class Definition10.16.1 Class Definition According to (ANSI) IEEE C57-13.1-

1981 ProtectionAccuracy classes for metering:The accuracy has to be kept for all power factors in the range of 0.6 to 1.

10.16.2 Class Definition According to IEC 60044-6

Metering class At 100% rated current x RF At 10% rated currentmin max min max

0.3 0.997 1.003 0.994 1.0060.6 0.994 1.006 0.988 1.0121.2 0.988 1.012 0.976 1.024

Max. peak instantaneous error at accuracy limit condition 20 x IpnClass Max. peak instantaneous error in % at 20 x Ipn

C ε = 10K ε = 10 AND Vb < 0.7 x Ukn

T ε = 10

Class At rated primary current At accuracy limit conditionRatio error

in %Phase displacement Max. peak instantaneous

error in %min centiradiansS nd ε = 10

TPS 0.25 ε = 10TPX 0.5 30 0.9 ε = 10TPY 1.0 60 1.8 ε = 10TPZ 1.0 180 ± 18 5.3 ± 0.6 ε = 10

CT Analyzer

194

10.16.3 Class Definition According to IEC 60044-1

Instrument transformers according to 60044-1Limits for measuring current transformer classes from 0.1 to 1:

Limits for special application transformers:

Accuracy class Permitted current (ratio) error (± in %) at percentage of rated current Ipn

5% of Ipn 20% of Ipn 100% of Ipn 120% of Ipn0.1 0.4 0.2 0.1 0.10.2 0.75 0.35 0.2 0.20.5 1.5 0.75 0.5 0.51.0 3.0 1.5 1.0 1.0

Accu-racy class

Permitted phase displacement (±) at percentage of rated current Ipn

in minutes in centiradians5% 20% 100% 120% 5% 20% 100% 120%

0.1 15 8 5 5 0.45 0.24 0.15 0.150.2 30 15 10 10 0.9 0.45 0.3 0.30.5 90 45 30 30 2.7 1.35 0.9 0.91.0 180 90 60 60 5.4 2.7 1.8 1.8

Accuracy class

Permitted current (ratio) error (± in %) at percentage of rated current Ipn

1% of Ipn 5% of Ipn 20% of Ipn 100% of Ipn 120% of Ipn0.2S 0.75 0.35 0.2 0.2 0.20.5S 1.5 0.75 0.5 0.5 0.5

Accu-racy class

Permitted phase displacement (±) at percentage of rated current Ipn

in minutes in centiradians1% 5% 20% 100% 120% 1% 5% 20% 100% 120%

0.2S 30 15 10 10 10 0.9 0.45 0.3 0.3 0.30.5S 90 45 30 30 30 2.7 1.35 0.9 0.9 0.9


195

Limits of current error for measuring current transformers (class 3 and 5):

The load must have a cos ϕ of 0.8 if the load is above 5VA and a cos ϕ of 1 if it is between 1 and 5VA. A load < 1VA is not allowed (see IEC 60044-1, section 11.2).

Error limits for protection CTs according to IEC 60044-1

Accuracy class Permitted current (ratio) error (± in %) at percentage of rated current Ipn

50% of Ipn 120% of Ipn3 3 35 5 5

Accuracy class

Permitted current error (±) at rated primary

current

Permitted phase displacement (±) at

rated primary current

Composite error at rated accuracy

limit primary current

in % minutes centiradians in %5P 1 60 1.8 510P 3 - - 10

CT Analyzer

196

10.17 Determination of Transient Dimensioning Factor (Ktd)

10.17.1 Calculation for Class TPZCalculated according to IEC 60044-6, A5:

10.17.2 Calculation for Class TPX, TPYA worst case value is calculated. All formulas given below are calculated and the worst case value is taken.

Step 1 Calculation of Ktf at tmax.

Ktd at tmax is calculated according to IEC 60044-6, A5:

Step 2Calculation of Ktd at accuracy limiting time of cycle 1:

1)

+⎟⎟⎠

⎞⎜⎜⎝

⎛==

− ps

PTTT

pPtftd TsT

TKK ω = Ktf at tmax

1)

+⎟⎟⎠

⎞⎜⎜⎝

⎛==

− ps

PTTT

pPtftd TsT

TKK ω = Ktf at tmax

⎟⎟⎠

⎞⎜⎜⎝

⎛−

=TsT

TTTT

t p

sp

sp ln*)(

*max

1)(

'''

+⎪⎭

⎪⎬⎫

⎪⎩

⎪⎨⎧

⎥⎥⎦

⎤

⎢⎢⎣

⎡−

⎥⎥⎦

⎤

⎢⎢⎣

⎡

−=

−−

s

al

p

al

Tt

Tt

sp

sptd ee

TTTT

KωKtd’ for single duty cycle (CO):


197

Step 3Calculation of Ktd at accuracy limiting time of cycle 2 (if defined).

Ktd'' for COCO cycle with consideration of remanence:

Consideration of Remanence

In order to consider the remanence in the term , we limit the value of the term to the remanence value. Therefore, the value of this term cannot be smaller than 0.8, if the remanence is 0.8.

In M A I N M E N U -> S E T T I N G S -> K T D C A L C U L A T I O N, you can select whether you want to have Ktd calculated according to IEC 60044-6 (remanence not considered) or according to Omicron (remanence considered).

Result: The highest of the values Ktd, Ktd’ or Ktd’’ is the value used for Ktd.

1)(

1)(

'''')''(''" +

⎥⎥⎦

⎤

⎢⎢⎣

⎡−

⎥⎥⎦

⎤

⎢⎢⎣

⎡

−+

⎪⎭

⎪⎬⎫

⎪⎩

⎪⎨⎧

+⎥⎥⎦

⎤

⎢⎢⎣

⎡−

⎥⎥⎦

⎤

⎢⎢⎣

⎡

−=

−−+−−−

s

al

p

al

s

alfr

s

al

p Tt

Tt

sp

spTtt

Tt

Tt

sp

sptd ee

TTTT

eeeTTTT

Kωω

s

alfr

Ttt

e)''( +−

CT Analyzer

198

10.18 Parameter Search Function (Guesser Function)

Start

Resistance measurement

Guess I-sn(see page 199)

no

yes

Overview

no

yes

no

yes

no

yes

no

yes

no

yes

Guess P/M(see page 199)

Guess burden(see page 204)

Guess parameter for IEC 60044-1(see page 200)

Guess parameter for IEC 60044-6(see page 201)

Guess parameter for ANSI

(see page 200)

Standard 60044-1

?

Standard 60044-6

?

Standard ANSI

?

P/M = ?

VA = ?

Excitation measurement

I-sn = ?

Ratio measurement

no

yes

no

yes

no

yes

Guess I-pn(see page 199)I-pn = ?

Guess class for IEC 60044-1

(see page 202)Standard 60044-1

?

Guess class for ANSI

(see page 203)Standard

ANSI?

End


199

Isn guessing(secondary current)

Ipn guessing(primay current)

P/M guessing(protection or measurement CT)

Start

noRct < 1 ohm

?

yes

I-sn = 5 A I-sn = 1 A

End

Start

End

Calculate Ip:

Ip = I-sn * Ncore

I-pn = nearest standard value for Ip or its decimal

multiples or fractions

Standard values [A]:

1, 510, 12, 12.5, 15, 16, 1820, 24, 2530, 32, 35, 3640, 48506072, 7580

yes

yes

no

no

Start

I-sn = 1 A?

I-sn = 5 A?

End

V-knee < 100 V

?

V-knee < 20 V

?

yes

no

yes

no

P/M = protection core

P/M = measurement

core

CT Analyzer

200

Parameter guessing for IEC 60044-1

Parameter guessing for IEEE C57.13 (ANSI)

yes

no

Start

Ts = ?yes

no

yes

no

yes

no

P/M = P?

Class = PX?

Class = ..PR?

Guess Ts:Ts = Ls/Rs

(see page 188)

Guess Ek/Ie:Ek = knee pointIe = Iexc at Ek

Guess E1/Ie1:E1 = knee pointIe1 = Iexc at E1

Secondknee point?

no

yes

Guess Kx:Kx = Ip/I-pn

(see page 188)

Guess FS:FS = Ip/I-pn

(see page 179)

Choose the next higher standard value from table.

Guess ALF:ALF = Ip/I-pn

(see page 184)

Choose the next lower standard

value from table.

End

Standard values ALF:510152030

Standard values FS:11.52510152030

Ts = ?

yes

no

Start

P/M = P?

End

Guess Vb:Vb = 20 * I-sn * Zb

Choose the next lower standard

value from table.

Standard values Vb [V]:102050100200400800


201

Parameter guessing for IEC 60044-6

yes

no

Start

Guess Kssc:Ucore at 10% ε^Kssc = Ucore / (Ktd * Zs * I-sn)Choose the next lower standard

value from table.

Ts = ?yes

no

yes

no

yes

no

Class = TPY or TPZ

?

Guess Ts:

Ts = Ls/Rs

Guess Val/Ial:Val = knee point

(ΔIexc/ΔEk = 10% : 100%)

Ial = Iexc at Ek

Class = TPS ?

Class = TPZ ?

Second knee point

?

no

yes

Guess E1/Ie1:E1 = knee point 1Ie1 = Iexc at E1

Guess Ktd for TPX/TPY:

Calculate Ktd

Guess Ktd for TPZ:

Calculate Ktd

End

Guess Kssc:Kssc = Emax / (Ktd * Zs * I-sn)Choose the next lower standard

value from table.

Guess Kssc:Kssc = Val /

(Ktd * Zs * I-sn)Choose the next lower standard

value from table.

Standard values Kssc:357.51012.51517.52025304050

CT Analyzer

202

Class guessing for IEC 60044-1

no

yes

Start

P/M = M?

P

M

Assess class 0.1

Class ok?yes

no

Assess class 0.2S

Class ok?yes

no

Assess class 0.2

Class ok?yes

no

Assess class 0.5S

Class ok?yes

no

Assess class 0.5

Class ok?yes

no

Assess class 1

Class ok?yes

no

Assess class 3

Class ok?yes

no

Set class = 5 Apply class

End


203

Class guessing for IEEE C57.13 (ANSI)

no

yes

Start

P/M = M?

P

M

Assess class 0.3

Class ok?yes

no

Assess class 0.6

Class ok?yes

no

Set class = 1.2 Apply class

End

Set class = K Set class = C

yes

noKnee point ≥ 0.7 * Vb

?

CT Analyzer

204

10.19 Guesser Algorithm for Burden

ANSI-30 KP found?No

End

Yes

Set Uref equal to the voltage of the highest point of the excitation

curve

Start

KPANSIref UU 30=

Get Standard

Standard = IEC-6?

Yes

Kssc specifed?

Yes

Ktd specifed?

Yes

CT Class = TPS?

Yes

No

K specifed?

No Yes

KFactor =*

KtdFactor =*

No

Meas CT?

Yes

No

Class Specified?

Yes

Get CT Type

FSFactor =

maxmax _BrdMCTBrd =

Get Isec

FactorIU

Brd refref

sec**3.1=

Search the burden value (Brd) which corresponds to the VAref in the appropriate

burden table.

Burden Table = MCT_IEC

Standard = IEC-1?

Yes

No

Burden Table = MCT_ANSI

Brd_max initialized?

Yes

),min( maxBrdBrdBrd =No

KsscFactor =

Burden Table = PCT_IEC

Cos phi specified?

Yes

NoANSI Standard?

Yes

No

Meas CT?

Yes

No

9.0=ϕCos 5.0=ϕCos

Brd >=5.0VA?

No

Yes

8.0=ϕCos 0.1=ϕCos

ALFFactor =

ALF specified?

Yes

0.10=Factor

Burden Table = PCT_IEC

Burden Table = PCT_ANSI

0.5=Factor

No

No

0.10=Factor

No

PCT_IEC: 1.0, 2.0, 2.5, 5.0, 7.5, 10.0, 12.5, 15.0,22.5, 20.0, 22.5, 30.0, 45.0, 50.0, 60.0 VA

PCT_ANSI: 25.0, 50.0, 100.0, 200.0 VA

MCT_IEC: 1.0, 2.0, 2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 22.5, 20.0, 22.5, 30.0 VA

MCT_ANSI: 2.5, 5.0, 12.5, 22.5 VA

IECBrdPCTBrd maxmax _=

No

Class Specified?

Yes

NoClass <> PX?

Yes

Standard = IEC-1?

No

Yes

IECBrdPCTBrd maxmax _=

No

VABrdPCT IEC 30_ max =

VABrdPCT ANSI 50_ max =

VABrdMCT 15_ max =


205

10.20 Burden Entry LogicDepending on whether• the test contains a Burden card or not, • the burden is defined in the CT-Object card or not, and• the parameter "I-sn" is defined in the CT-Object card or not,

the CT Analyzer reads the burden value from a different source. The "Burden" parameter defines the operating burden connected to the CT and therefore distinguishes from the "VA" parameter which defines the nominal burden the CT is made for.• Default values:

If the test does not contain a Burden card, the default burden value is "?". Therefore, the software tries to determine the correct burden using the guesser function (refer to section 10.19 ”Guesser Algorithm for Burden” on page 204).If a Burden card is included in the test, a "?" is entered for the "Burden" parameter in the CT-Object card to indicate that the burden has to be found by the CT Analyzer by means of a burden test. Entering a value for the "Burden" parameter in the CT-Object card is not possible until the test is finished.

• Behavior after the C L E A R R E S U L T S soft key has been pressed:If the test does not contain a Burden card, the burden value is changed to "?", if the CT Analyzer determined the burden using the guesser function. If a value was entered in the CT-Object card, this value is not changed.If a Burden card is included in the test, a "?" is entered for the "Burden" parameter in the CT-Object card to indicate that the burden has to be found by the CT Analyzer by means of a burden test. Entering a value for the "Burden" parameter in the CT-Object card is not possible until the test is finished.

The following table defines the behavior of the CT Analyzer depending on the specified definitions and parameters.

CT Analyzer

206

Burden card included in the

test

"Burden" parameter in

CT-Object card

Behavior of the CT Analyzer

No Value defined (e.g. 10VA)

All calculations are performed with the burden value defined in the CT-Object card (10VA).

No "?" All calculations are performed with the burden value measured during the excitation test.

The burden is calculated and entered into the "Burden" field after the excitation test.

Yes "?" All calculations are performed with the burden value measured during the burden test.

The burden is calculated and entered into the "Burden" field after the burden test.

Value entry in the "Burden" field in the CT-Object card is not possible until the test is finished.

Yes Value defined (e.g. 10VA)

The value in the "Burden" parameter field is automatically changed to "?" when the Burden card is added, even if a value has been entered before.

Parameter Definition Syntax for the Different Standards

207

11 Parameter Definition Syntax for the Different Standards

11.1 How to Read the Parameter Definition Syntax ChartsThe parameter definition syntax charts shown on the following pages have to be read from the left to the right. How to read them is described below using the IEC 60044-1 chart on page 208 as an example:

1. First, the standard has to be defined (in our example: "IEC 60044-1").

2. Then you have to define whether the CT is a protection CT or a measurement CT ("P" or "M"). If you do not define this parameter ("?"), class definition is not possible.

3. After this, the class has to be defined. Depending on whether the CT is a measurement CT ("M") or a protection CT ("P"), a different set of classes is available. If no class definition is done ("?"), it is not possible to define an overcurrent number and no assessment of the calculated results can be performed.

4. If you have defined the class of the CT, you have to enter an overcurrent number.

5. If you have previously defined the class and the overcurrent number, the CT Analyzer performs a calculation of the results and performs an assessment for ALF and the class (in case of a protection CT) or for FS and the class (in case of a measurement CT.

If no class definition has been performed ("?" for the class definition), the CT Analyzer performs a calculation of the results but is not able to perform an assessment.

CT Analyzer

208

11.2 Parameter Definition Syntax for IEC 60044-1

Results:Knee point: 10/50, UKnee, IKnee, ALF, TS, LS, Lm, Kr, Excit. curve, Ratio, εc, RCT, Class

IEC 60044-1 P

M

(?)

5P

10P

?

ALF (?)1-300

Softkeys?, 5, 10,

15, 20, 30

Standard Protection [P]/Measuement [M] Class Overcurrent

Number

0,1

0,2S0,5

0,2

0,5S135

?

FS (?)1-30

Softkeys FS 1,

1,5, 2, 5,10, 15, 20, 30

Assessments:ALF >= ALF from settings (Object page)Rct <= RCT from settingsClass: Ratio-Err <= 1% (5P) or 10% (10P) Phase-Err <= 60 min (5P) εc,<= 5% (5P) or <= 10% (10P)

Assessments:FS, Fsi, RctClass: Ratio and phase error is within limits according to IEC 60044-1

Results:Knee point: 10/50FS, TS, LS, Lm, Kr, Excitation curve [ARMS], UKnee, IKnee , Ratio, εc, Class, RCT

Results:Knee point: 10/50, UKnee, IKnee,ALF/FS, TS, LS, Lm, Kr, Excitation curve, Ratio, εc, RCT, Class

Assessments:According to guessed parameters

Assessments:According to guessed parameters

Results:Knee point: 10/50FS, TS, LS, Lm, Kr, Excitation curve [ARMS],UKnee, IKnee , Ratio error (ε, Phase error, εc, Class, RCT

?

ALF (?)1-300

Results:Knee point: 10/50, UKnee, IKnee, ALF, TS, LS, Lm, Kr, Excit. curve, Ratio, εc, RCT, Class

Assessments:ALF >= ALF from settings (Object page)Kr <= 10%Rct <= Rct from settingsClass: Ratio-Err <= 1% (5P) or 3% (10P) Phase-Err <= 60 min (5P) εc,<= 5% (5P) or <= 10% (10P)

Results/Assessments

Ie

Ek

?

?

RCT

Kx (?)

??

Results:Knee point: 10/50, VKnee, IKnee, Kx, Ek, Ie, E1, Ie1, TS, LS, Lm, Kr, Excit. curve, Ratio, εc, RCT, Class

Assessments:Kx, EK, Ie, E1, Ie1, RCTClass: εc,<= 0.25% (Turns ratio error)

PX

5PR

2P3P4P

6P

10PR

2PR3PR4PR

6PR

RCT ?

RCT ?

RCT ?

Ext(120%)

Ts ?

?

Ie1?

E1?

?

?

?

?

Values in brackets () are default values.


209

11.3 Parameter Definition Syntax for IEC 60044-6 Classes TPS and TPZ

IEC

600

44-6

TPS

TPZ

Kssc

1-30

0(1

0)S

oftk

eys

3, 5

, 7.5

, 10,

12

.5, 1

5, 1

7.5,

20

, 25,

30,

40,

50

, 100

Stan

dard

Cla

ssO

verc

urre

nt n

umbe

r and

ex

tend

ed d

efin

ition

Res

ults

/Ass

essm

ents

Res

ults

: Kn

ee p

oint

: 10/

50,

V Kne

e, I K

nee,

K SS

C ,

Ts, L

S, L

m,

Kr,

Exc

it. c

urve

(Vem

f, I P

EA

K),

Val, I

al, E

1, Ie

1, e

t, R

CT,

R

atio

, P

hase

, Pol

arity

, N

Ass

essm

ents

:K*

KSS

C,

I al, V

al,E

1, R

ct,

Cla

ss: e

t, =<

0.2

5%,

K SSC

I al

?V al

??

T P

(20

ms)

K td ?R

CT

T P(0

ms)

K (1) ???

Res

ults

:Kn

ee p

oint

: 10/

50U

Kne

e, I K

nee,

K SS

C, K

td, T

s, L S

, L m

, Kr,

E

xcit.

cur

ve (V

emf,

I PE

AK),

Rat

io, P

hase

, Pol

arity

, RC

T

Ass

essm

ents

:K t

d*K S

SC,

RC

T,Ts

= +

- 10%

Ts S

ettin

g,C

lass

:

Rat

io-E

rr <

= 1%

Ph

ase-

Err <

= 18

0+-1

8 m

in

T S

? RC

T ?I e1E1

??

Dut

y cy

cle

defin

ition

Valu

es in

bra

cket

s ()

are

de

faul

t val

ues.

CT Analyzer

210

11.4 Parameter Definition Syntax for IEC 60044-6 Classes TPX and TPY

IEC

600

44-6

TPX

TPY

Stan

dard

Cla

ssO

verc

urre

nt n

umbe

r and

ex

tend

ed d

efin

ition

s

C-t1

-O

C-t1

-O-t f

r-C

-t2-O

t1[1

-5.0

00s]

t1[1

-5.0

00s]

(0.1

00s)

t fr[1

-5.0

00s]

(0.3

00s)

t2[1

-5.0

00s]

(0.1

00s)

Res

ults

:Kn

ee p

oint

: 10/

50,

V Kne

e, I K

nee,

K SS

C, K

td, T

s,

L S, L

m, K

r,

Exc

it. c

urve

(Vem

f, A

PE

AK),

V al,

I al, e

, Em

ax, R

CT,

Rat

io,

Phas

e, P

olar

ity, N

Ass

essm

ents

:K d

t*Kss

c, R

CT,

C

lass

:

e@

Kss

c*K

td <

= 10

%,

R

atio

-Err

<= 0

.5%

;

Phas

e-Er

r <=

30 m

in

Dut

y cy

cle

defin

ition

K SS

C

T S

T P(2

0ms)

K td

(?)

(?)

t al1

(40m

s)

t al1

(40m

s) t al2

(40m

s)

K SS

C

K td

(?)

(?)

(?)

RC

T

(?)

RC

T

(?)

T P(2

0ms)

C-t1

-O

C-t1

-O-t f

r-C

-t2-O

t1[1

-5.0

00s]

(0.1

00s)

t1[1

-5.0

00s]

(0.1

00s)

t fr[1

-5.0

00s]

(0.3

00s)

t2[1

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00s]

(0.1

00s)

t al1

(40m

s)

t al1

(40m

s) t al2

(40m

s)

Res

ults

:Kn

ee p

oint

: 10/

50,

V Kne

e, I K

nee,

K SS

C, K

td, T

s, L

S,

L m, K

r,

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it. c

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(Vem

f, A P

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),V a

l, I al

, EP

S^,

Em

ax, R

CT,

R

atio

, P

hase

, Pol

arity

, N

Ass

essm

ents

:K d

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Cla

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,

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Res

ults

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defa

ult v

alue

s.


211

11.5 Parameter Definition Syntax for IEEE C57.13

IEEE C57.13

P

M

?

C

K

T

Vb100-1200

default 100

Softkeys10, 20, 50, 100, 200, 400, 800

Standard Protection [P]/Measuement [M] Class Max.

Terminal Voltage (Vb)

0.6

1.2

0.3

Results:Knee point: ANSI 30/45, UKnee, IKnee, Vb, TS, LS, Lm, Kr, Excitation curve [ARMS], Ratio, RCT

Assessments:Vb, Vknee (only K class)

Assessments:Class: Ratio and phase error is within limits according to IEEE C57.13

Results:Knee point: ANSI 30/45, UKnee, IKnee, FS, TS, LS, Lm, Kr, Excitation curve [ARMS], Ratio, RCT

Results:Knee point: ANSI 30/45, UKnee, IKnee Vb, TS, LS, Lm, Kr, Excitation curve [ARMS], Ratio, RCT

Assessments:-

RF 1

RF 2RF 1.5

default 2

RF 3RF 4

Thermal current rating factor

default0.3

B-0.2

B-0.9B-0.5

B-0.1

B-1.8

defaultB-0.2

Burden definition

B-1

B-4

B-2

B-8

defaultB-2

Burden definition

?Results:Knee point: ANSI 30/45, UKnee, IKnee Vb, TS, LS, Lm, Kr, Excitation curve [ARMS], Ratio, RCT

Assessments:-

Results/Assessments

RCT ?

RCT ?

Misc.

CT Analyzer

212

Care and Cleaning

213

12 Care and CleaningThe CT Analyzer does not require any special maintenance or care. Clean the device from time to time or as necessary using a cloth dampened with water or isopropanol alcohol.

CT Analyzer

214

Technical Data

215

13 Technical DataGuaranteed data are specified for an ambient temperature of 23°C ± 5°, a power supply of 115/230VAC, and after a warm-up time longer than 15 minutes.

Guaranteed data are valid for the period of one year after factory adjustment.

13.1 Mains Power SupplyTable 13-1:Technical data for mains power supply

13.2 Generator OutputTable 13-2:Technical data for generator output

Mains power supplyConnection Connector according to IEC 60320Voltage, single phase

– rated voltage

– permitted range

110/230VAC

85 - 264VACMains fuses 2 x T6A H 250V,

(high-breaking capacity wire fuse 5 x 20mm)Power consumption 500VA max.Frequency

– rated frequency

– permitted range

50/60Hz

45 - 65HzOvervoltage category II

Generator outputOutput current 0 - 5Arms (15Apeak)

Output voltage 0 - 120VACOutput power 0 - 400VArms (1500VApeak)

CT Analyzer

216

13.3 Measurement InputsTable 13-3:Technical data for measurement input "Sec"

Table 13-4:Technical data for measurement input "Prim"

13.4 Winding Resistance AccuracyTable 13-5:Winding resistance accuracy

Measurement input "Sec"Voltage ranges 0 - 0.3 / 3 / 30 / 300VAC (auto ranging)

Accuracy 0.1% guar.Input impedance 0 - 15V: 1MΩ

15 - 300V: 500kΩ to 1MΩ, depending on the voltage. Input current is compensated by the device.

Insulation Reinforced insulation (R) to all other circuits

Measurement input "Prim"Voltage ranges 0 - 0.03 / 0.3 / 3 / 30VAC (auto ranging)

Accuracy 0.1% guar.Input impedance 0 - 15V: 330kΩ

15 - 30V: 120kΩ to 330kΩ, depending on the voltage.

Insulation Reinforced insulation (R) to all other circuits

Winding resistance accuracyResolution 1mΩAccuracy

– typical – guaranteed

0.05 %0.1 % + 1 mΩ

Technical Data

217

13.5 Ratio and Phase AccuracyThe values given in the following table are only valid under the following conditions:• All utility lines to the primary side of the CT are disconnected.• One terminal of the primary side of the CT is connected to PE.• The original measurement cables delivered by OMICRON for the

CT Analyzer are used.

• The CT under test is a CT with a non-gapped core.

• The knee point voltage according to IEEE C57.13 is > 3V.

Under interfering conditions the device has reduced accuracy.Values without the prefix "!" in the ratio table of the Ratio card have guaranteed accuracy. The accuracy of values marked with a "!" in the table is reduced by factor 2 since these values are not directly measured but calculated from the measured values instead.

Table 13-6:Accuracy of ratio values displayed in the ratio table (1 A CTs )

Table 13-7:Accuracy of ratio values displayed in the ratio table (5 A CTs )

Ratio accuracy for 1 A CTs at rated currentCT ratio I-sn Rated power1

1. Nominal burden of the CT.

Typical accuracy

Guaranteed accuracy

0.2 - 1 1 1.0 - 15VA 0.05% 0.1%1 - 2000 1 0 - 15VA 0.02% 0.05%

2000 - 5000 1 0 - 15VA 0.03% 0.1%5000 - 10000 1 0 - 15VA 0.05% 0.2%

Ratio accuracy for 5 A CTs at rated currentCT ratio I-sn Rated power1

1. Nominal burden of the CT.

Typical accuracy

Guaranteed accuracy

0.2 - 1 5 1.0 - 75VA 0.05% 0.1%1 - 2000 5 0 - 75VA 0.02% 0.05%

2000 - 5000 5 0 - 75VA 0.03% 0.1%5000 - 10000 5 0 - 75VA 0.05% 0.2%

CT Analyzer

218

Table 13-8:Phase accuracy

Table 13-9:Turns ratio accuracy

Phase accuracy at rated currentResolution 0.01min

Accuracy (cos ϕ 0.8 - 1)– typical – guaranteed

1 min3 min

Turns ratio accuracyResolution 0.01 turnsAccuracy

– typical – guaranteed

0.05 %0.1 %

Technical Data

219

13.6 Insulation CoordinationTable 13-10:Insulation coordination Insulation coordination

Potential group Working voltage

Insul. type1

1. R = Reinforced insulationB = Basic insulation

Test volt. VACrms50/60Hz

Creepage Clearance

Insulation between mains and any other potential group inside the device except earth (housing)

400V R typ. 3.7kV > 8mm > 6.5mm

Insulation between mains and earth

230V B 1350VAC > 3mm > 1.5mm

Insulation between SELV potential and mains (CF slot, remote control interface)

230VAC R 4kV > 8mm > 6.5mm

Insulation between 30V/300V inputs and SELV or output potential group

300V R 6kV2

2. Inputs and outputs are protected against overvoltages by surge arresters to PE. Voltages above 350 V (input "PRIM", "Output") or above 600 V (input "SEC") will fire the surge arresters and cause the input/output to be shorted to PE.

> 6.4mm > 5.9mm

Insulation between power output and SELV

125V250V

or 400V

R 2.7kV2 > 6.5mm 4 mm

Note: Since some potential groups are protected by surge arresters, it is not possible to test the insulation of a series production device with the according test voltages given in the table.

CT Analyzer

220

13.7 Compact Flash Card InterfaceTable 13-11:Compact Flash Card Interface

13.8 Remote Control InterfaceThe remote control interface can only be used with the corresponding remote control software for PC.

Figure 13-1:Pin assignment for remote control interface

Figure 13-2:Connection cable for remote control interface

Compact Flash card interfaceCard type CF type 1Allowed memory size 16MB - 2GB

1 nc2 RxD (data in / receive)3 TxD (data out / transmit)4 nc5 GND (signal ground)

6 nc7 RTS (out)8 CTS (in)9 + 5 V

Do not connect! For internal use only!

Housing: Shield (ground)

9-pole SUB-D connector, male

Figure shows outside view onto the pins at the CT Analyzer!

Connections required:1 2 3 4 5 6 7 8 shield

1 2 3 4 5 6 7 8 shield

9-pole (DB9) null modem or crossover cable, 2 x female

Technical Data

221

13.9 Environmental ConditionsTable 13-12:Environmental conditions

13.10 Electromagnetic Compatibility (EMC)Table 13-13:Electromagnetic compatibility

Environmental conditionsOperating temperature 32 ... 122°F (0 ... 50°C)Storage and transport -13 ... 158°F (-25 ... +70°C)Humidity range 5 ... 95% relative humidity, non-condensingVibration and shock Tested acc. to IEC 60068-2-6, Test Fc: Sinusoidal

vibration 10 - 150 Hz, 20 sweeps with 2g.

Tested acc. to IEC 60068-2-27, Test Ea: Half sine shock, 11ms duration, 3 shocks with 15g.

Tested acc. to IEC 60068-2-78, Cab, Damp Heat: Temp. 20°C, duration 48h, rel. humidity 95%.

Electromagnetic compatibilityCE conformity The product adheres to the specifications from

the guidelines of the council of the European community for meeting the requirements of the member states regarding the electromagnetic compatibility (EMC Standard 89/336/EEC).

Emissions

– International

– Europe

FCC Subpart B of Part 15 Class A

EN 50081-2Susceptibility

– International

– Europe

IEC 1000-4-2/3/4/5/6

EN 50082-2:1992

CT Analyzer

222

13.11 Safety StandardsTable 13-14:Safety standards

13.12 Weight and DimensionsTable 13-15:Weight and dimensions

Safety standardsInternational standards IEC 1010-1

UL 3111-1

CAN/CSA-C22.2 No. 1010.1-92European standards EN 61010-1:1993

EN 60950 +A1:1993-05

Weight and dimensionsWeight < 8kg without accessoriesDimensions (w x h x d) 360 x 285 x 145 mm

Scope of Delivery and Accessories

223

14 Scope of Delivery and Accessories

14.1 CT Analyzer CT1 incl. AccessoriesTable 14-1:CT Analyzer CT1 incl. accessories, VE000652

14.2 CT Analyzer Standard PackageTable 14-2:CT Analyzer standard package, VE000650

Description Article numberCT Analyzer CT1 incl. accessoriesIncluded parts:

VE000652

1 CT Analyzer standard package VE0006501 Accessories set for CT Analyzer VEHK0650

Description Article numberCT Analyzer standard packageIncluded parts:

VE000650

1 CT Analyzer hardware VEGG06501 Compact Flash card 128MB (memory space for at

least 416 test reports)VEHZ0653

1 USB 2.0 Compact Flash card reader VEHZ06551 USB - RS232 Converter and Cable VEHZ00141 RS232 Nullmodem Cable 3m VEHK00321 Power cord (country-dependent)1 User Manual VESD06051 CT Analyzer PC Toolset software for CT Analyzer

with CTA Remote Control software, CTA Quick Test, CTA Remote Excel File Loader and other tools.

VESM0800

1 CPC Explorer software, PC software for visualization and handling of test reports

VESD6004

CT Analyzer

224

14.3 Accessories Set for CT AnalyzerTable 14-3:Accessories set for CT Analyzer, VEHK0650

Description Article numberAccessories set for the CT AnalyzerIncluded parts:

VEHK0650

1 Coax measurement cable set with banana plugs, 2 x 3m, 1 x 10m

VEHK0651

1 Battery clamp set with 4mm banana sockets for primary side connection, consisting of one red and one black battery clamp

VEHZ0652

1 Crocodile clamp set (2 x red, 2 x black), 20 mm opening width

VEHZ0656

1 Grounding (PE) cable (gn/ye), 1 x 6m, 6mm2, used for protective earth connection

VEHK0615

6 Flexible terminal adapters with 4mm banana socket1 USB - RS232 Converter and Cable VEHZ00141 RS232 Nullmodem Cable 3m VEHK00321 Carry bag for the CT Analyzer VEHP0018


225

14.4 Additional Accessories for CT AnalyzerTable 14-4:Additional accessories for the CT Analyzer

Pcs. Description Article number1 Coax measurement cable set with banana plugs,

2 x 3m, 1 x 10mVEHK0651

1 Coax measurement cable with banana plugs, 3m VEHK06541 Coax measurement cable with banana plugs, 6m VEHK06521 Coax measurement cable with banana plugs, 10m VEHK06531 Coax measurement cable with banana plugs, 15m VEHK06551 Coax measurement cable with banana plugs, 100m VEHK06561 Coax measurement cable set with Kelvin clamps,

3m (for measurement during production and on 5A CTs)

VEHK0657

1 Battery clamp set with 4mm banana sockets for primary side connection, consisting of one red and one black battery clamp

VEHZ0652

2 Crocodile clamp for secondary side connection with 4mm banana socket (1 black and 1 red clamp)

VEHZ0651

1 Crocodile clamp set (2 red + 2 black clamps), 20 mm opening width

VEHZ0656

1 Grounding (PE) cable (gn/ye), 1 x 6m, 6mm2, used for protective earth connection

VEHK0615

12 Flexible terminal adapters with 4mm banana socket VEHS00091 Compact Flash card 32MB (memory space for at

least 100 test reports)VEHZ0653

1 Compact Flash card 128MB (memory space for at least 416 test reports)

VEHZ0654

1 USB 2.0 Compact Flash card reader VEHZ06551 USB - RS232 Converter and Cable VEHZ00141 RS232 Nullmodem Cable 3m VEHK00321 Training CT, 300:5, class 0.5 FS 5 VEHZ06431 Calibration CT, 2000:1 / 2000:5, class 0.02 VEHZ06491 Transport case for the CT Analyzer with wheels VEHP00681 Carry bag for the CT Analyzer VEHP00181 CT Analyzer Add-On Manual

(provides theoretical backgrounds and normative definitions, only available in English)

VESD0607

CT Analyzer

226

Figure 14-1:Accessories (1)

Battery clamp set with 4mm banana sockets for primary side connection (VEHZ0652)

Crocodile clamps for secondary side connection with 4mm banana socket (VEHZ0651)

Coax measurement cable with 4mm banana plugs, length 3m, 6m, 10m, 15m or 100m(VEHK0652 - VEHK0656)

Crocodile clamps with 20 mm opening width (VEHZ0656)

Coax measurement cable with Kelvin clamps, length 3m(VEHK0657)


227


Flexible terminal adapters with 4mm banana socket (VEHS0009)

Compact Flash card reader (VEHZ0655, symbolic representation)

USB - RS232 Converter and Cable (VEHZ0014, left) andRS232 Nullmodem Cable 3m (VEHK0032)

Calibration CT (VEHZ0649)

Grounding cable (VEHK0615)

Training CT (VEHZ0643)

CT Analyzer

228


Transport case with wheels (VEHP0068)

Carry bag (VEHP0018)

Contact Information / Technical Support


Europe, Africa, Middle EastOMICRON electronics GmbH

Phone: +43 5523 507-333

E-Mail: [email protected]

Web: www.omicron.at

Asia, PacificOMICRON electronics Asia Ltd, Hong Kong

Phone: +852 2634 0377


Web: www.omicron.at

North and South AmericaOMICRON electronics Corp. USA

Phone: +1 713 830-4660 or 1 800 OMICRON


Web: www.omicronusa.com

For addresses of OMICRON offices with customer service centers, regional sales offices or offices for training, consulting and commissioning please see our website.

45


46

Index

231

Index4 wire connection vs. 2 wire connection . . . . 28

AAbout page (help system) . . . . . . . . . . . . . . . 38accessories . . . . . . . . . . . . . . . . . . . . . . . . . 224accuracy limiting current for IEC 60044-1 class PX (Ie) . . . . . . . . . . . . . . . . . . . . . 63, 81–82, 97accuracy limiting factor (ALF, ALFi) . . . . . . . . . . . . . . . . . . . . . . . . . . . 62, 79–80, 97

calculation . . . . . . . . . . . . . . . . . . . . . . . 184accuracy limiting secondary excitation current (Ial) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 65, 98accuracy limiting voltage for IEC 60044-1 class PX (Ek) . . . . . . . . . . . . . . . . . . . . . . . 63, 81–82address

OMICRON address . . . . . . . . . . . . . . . . 229ALF, refer to accuracy limiting factorALFi, refer to accuracy limiting factorambient temperature (default setting) . . . . . . 48ANSI

assessed parameters . . . . . . . . . . . . . . . 97class definition . . . . . . . . . . . . . . . . . . . . 193conditions for OK assessment . . . . . . . . 100excitation graph . . . . . . . . . . . . . . . . . . . . 85excitation test results . . . . . . . . . . . . . . . . 83parameter definition syntax . . . . . . . . . . 211

application examplesbar-type CT . . . . . . . . . . . . . . . . . . . . . . 152burden test . . . . . . . . . . . . . . . . . . . . . . . 157bushing-type CT . . . . . . . . . . . . . . . . . . 148delta winding transformer . . . . . . . . . . . 145freely accessible CT . . . . . . . . . . . . . . . 143gapped core . . . . . . . . . . . . . . . . . . . . . . 155GIS (SF6) switch gear . . . . . . . . . . . . . . 150multicore CTs . . . . . . . . . . . . . . . . . . . . . 157noise reduction techniques . . . . . . . . . . 158tapped CTs . . . . . . . . . . . . . . . . . . . . . . 154unwound core, excitation curve . . . . . . . 156wye winding transformer . . . . . . . . . . . . 147

Assessment card . . . . . . . . . . . . . . . . . . 35, 96assessed parameters . . . . . . . . . . . . . . . 97conditions for OK assessment . . . . . . . 100

automatic CT test . . . . . . . . . . . . . . . . . . . . . 31automatic parameter search . . . . . . . . . . . . 31

Bbag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 225bar-type CT

application example . . . . . . . . . . . . . . . 152basic wiring for burden test . . . . . . . . . . . . . 25basic wiring for CT test . . . . . . . . . . . . . . . . . 26block diagram . . . . . . . . . . . . . . . . . . . . . . . . 23Burden (parameter) . . . . . . . . . . . . . . . . . . . 61Burden card . . . . . . . . . . . . . . . . . . . . . . 35, 72

connecting the burden . . . . . . . . . . . . . . . 73overload indication . . . . . . . . . . . . . . . . . 72running the test . . . . . . . . . . . . . . . . . . . . 73test results . . . . . . . . . . . . . . . . . . . . . . . . 73test settings . . . . . . . . . . . . . . . . . . . . . . . 72

burden entry logic . . . . . . . . . . . . . . . . . . . . 205Burden parameter . . . . . . . . . . . . . . . . . . . . 73burden test

application example . . . . . . . . . . . . . . . 157bushing-type CT

application example . . . . . . . . . . . . . . . 148

Ccalibration . . . . . . . . . . . . . . . . . . . . . . . . . . 161care and cleaning . . . . . . . . . . . . . . . . . . . . 213cascading style sheet in CPC Explorer 140–141changing fuses . . . . . . . . . . . . . . . . . . . . . . . 13class definition

according to IEC 60044-1 . . . . . . . . . . . 194according to IEC 60044-6 . . . . . . . . . . . 193according to IEEE C57.13 . . . . . . . . . . . 193

Class multiplying factor . . . . . . . . . . . . . . . . 62Class parameter . . . . . . . . . . . . . . . . 60, 97–99cleaning . . . . . . . . . . . . . . . . . . . . . . . . . . . 213climate conditions . . . . . . . . . . . . . . . . . . . . 221

CT Analyzer

232

C (cont.)

Comment card . . . . . . . . . . . . . . . . . . . 35, 107Compact Flash card . . . . . . . . . . . . . . . 20, 225

technical data . . . . . . . . . . . . . . . . . . . . . 220Compact Flash card reader . . . . . . . . . . . . 225Company field . . . . . . . . . . . . . . . . . . . . . . . . 57composite error (εC) . . . . . . . . . . . . . . . . 91, 97computer requirements

for CPC Explorer . . . . . . . . . . . . . . . . . . 138for CT Analyzer PC Toolset . . . . . . . . . . 109

connecting a CT . . . . . . . . . . . . . . . . . . . 26, 31connecting burden for burden test . . . . . 25, 73connection clamps . . . . . . . . . . . . . . . . . . . 225connection techniques (4 wire & 2 wire) . . . . 28contact information

OMICRON address . . . . . . . . . . . . . . . . 229continuous current rating factor . . . . . . . . . . 71copying a file . . . . . . . . . . . . . . . . . . . . . . . . . 47Core field . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58core voltage, calculation . . . . . . . . . . . . . . . 178cos ϕ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61cos ϕ parameter . . . . . . . . . . . . . . . . . . . . . . 73Country field . . . . . . . . . . . . . . . . . . . . . . . . . 57CPC Explorer

changing language . . . . . . . . . . . . . . . . 141stylesheet . . . . . . . . . . . . . . . . . . . . 140–141toolbar buttons . . . . . . . . . . . . . . . . . . . . 140update . . . . . . . . . . . . . . . . . . . . . . . . . . 110

CPC Explorer softwarecreating a folder . . . . . . . . . . . . . . . . . . . . . . 46CSS in CPC Explorer . . . . . . . . . . . . . 140–141CT Analyzer Firmware Update tool . . . . . . . 131CT Analyzer PC Toolset . . . . . . . . . . . . . . . 109

start page . . . . . . . . . . . . . . . . . . . . . . . . 111CT test wiring . . . . . . . . . . . . . . . . . . . . . . . . 28CTA QuickTest . . . . . . . . . . . . . . . . . . . . . . 116CTA Remote Control software . . . . . . . . . . 136CTA Remote Excel File Loader . . . . . . . . . 123CTA Start Page . . . . . . . . . . . . . . . . . . . . . . 111CTA to NetSim Export . . . . . . . . . . . . . . . . . 137

CT-Object card . . . . . . . . . . . . . . . . . . . . 35, 56available soft keys . . . . . . . . . . . . . . . . . . 56location and object settings . . . . . . . 57, 126parameters and settings . . . . . . . . . 58, 126

current ratio error ε . . . . . . . . . . . . . . . . . 97–99cutting a file . . . . . . . . . . . . . . . . . . . . . . . . . 47

Ddate/time (setting) . . . . . . . . . . . . . . . . . . . . 48DC winding resistance . . . . . . . . . . . . . . 97–99dead time between first opening and reclosure (tfr) . . . . . . . . . . . . . . . . . . . . . 67, 69default settings . . . . . . . . . . . . . . . . . . . . . . . 48default test cards (setting) . . . . . . . . . . . . . . 48deleting a file or folder . . . . . . . . . . . . . . . . . 45Delta compensation . . . . . . . . . . . . . . . . . . . 62delta winding transformer

application example . . . . . . . . . . . . . . . 145designated use . . . . . . . . . . . . . . . . . . . . . . . 15dimensioning factor (K) . . . . . . . . . . . . . . . . 65dimensioning factor (Kx)

calculation . . . . . . . . . . . . . . . . . . . . . . . 188dimensioning factor for IEC 60044-1 class PX (Kx) . . . . . . . . . . . . . . . . . . 63, 80, 97dimensions . . . . . . . . . . . . . . . . . . . . . . . . . 222display contrast (setting) . . . . . . . . . . . . . . . 48display overview . . . . . . . . . . . . . . . . . . . . . . 22displaying a specific card . . . . . . . . . . . . . . . 36Δϕ parameter . . . . . . . . . . . . . . . . . . . . . 97–99duration of current flow (t1, t2) . . . . . . . . 67–68duty cycle . . . . . . . . . . . . . . . . . . . . . . . . 66, 68

Index

233

Eε parameter . . . . . . . . . . . . . . . . . . . . . . . 97–99e.m.f. rms voltage calculation . . . . . . . . . . . 178E1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64εC, refer to composite errorediting a card . . . . . . . . . . . . . . . . . . . . . . . . 37Ek, refer to accuracy limiting voltage for IEC 60044-1 class PXelectromagnetic compatibility (EMC) . . . . . 221electronic manual (PDF) . . . . . . . . . . . . . . . . 10e-mail

OMICRON address . . . . . . . . . . . . . . . . 229environmental conditions . . . . . . . . . . . . . . 221ε-peak, refer to peak instantaneous errorequipotential bonding . . . . . . . . . . . . . . . . . . 20error and warning messages . . . . . . . . . . . 163εt, refer to turns ratio errorExcitation card . . . . . . . . . . . . . . . . . 33, 35, 77

available soft keys . . . . . . . . . . . . . . . . . . 78excitation graph . . . . . . . . . . . . . . . . . . . . 85K-value graph . . . . . . . . . . . . . . . . . . . . . 88overload indication . . . . . . . . . . . . . . . . . . 77settings . . . . . . . . . . . . . . . . . . . . . . . . . . 78test results . . . . . . . . . . . . . . . . . . . . . . . . 78

excitation characteristicdetermination . . . . . . . . . . . . . . . . . . . . . . 33

excitation graph . . . . . . . . . . . . . . . . . . . . . . . 85available soft keys . . . . . . . . . . . . . . . 85, 88loading reference graph . . . . . . . . . . . . . . 86viewing measured values . . . . . . . . . 87, 89

explorer, refer to CPC Explorerexport, CTA to NetSim . . . . . . . . . . . . . . . . 137extended current rating . . . . . . . . . . . . . . . . . 64

Ff (parameter) . . . . . . . . . . . . . . . . . . . . . . . . . 61factory calibration, reset to . . . . . . . . . . . . . . 53features . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15Feeder field . . . . . . . . . . . . . . . . . . . . . . . . . . 57

File Handling (main menu) . . . . . . . . . . . . . . 44available functions . . . . . . . . . . . . . . . . . . 44

file systemcopying a file . . . . . . . . . . . . . . . . . . . . . . 47creating a folder . . . . . . . . . . . . . . . . . . . 46cutting a file . . . . . . . . . . . . . . . . . . . . . . . 47deleting a file or folder . . . . . . . . . . . . . . . 45loading a file . . . . . . . . . . . . . . . . . . . . . . 44navigating in . . . . . . . . . . . . . . . . . . . . . . 46pasting a file . . . . . . . . . . . . . . . . . . . . . . 47renaming a file . . . . . . . . . . . . . . . . . . . . . 44saving a file . . . . . . . . . . . . . . . . . . . . . . . 47

firmware update . . . . . . . . . . . . . . . . . . 52, 131formulas and definitions . . . . . . . . . . . . . . . 175freely accessible CT

application example . . . . . . . . . . . . . . . 143frequency . . . . . . . . . . . . . . . . . . . . . . . . . . . 61frequency (setting) . . . . . . . . . . . . . . . . . . . . 48FS, refer to instrument security factorFSi, refer to instrument security factorfunctional components . . . . . . . . . . . . . . . . . 19fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Ggapped core

application example . . . . . . . . . . . . . . . 155generator output

technical data . . . . . . . . . . . . . . . . . . . . 215GIS (SF6) switch gear

application example . . . . . . . . . . . . . . . 150glossary

symbols used in manual . . . . . . . . . . . . . . 9grounding cable . . . . . . . . . . . . . . . . . . . . . 225grounding connector . . . . . . . . . . . . . . . . . . 20Guesser algorithm for burden

flow chart . . . . . . . . . . . . . . . . . . . . . . . . 204Guesser function . . . . . . . . . . . . . . . . . . . . . 31

flow chart (burden) . . . . . . . . . . . . . . . . 204

CT Analyzer

234

Hhardware

block diagram . . . . . . . . . . . . . . . . . . . . . 23Compact Flash card slot . . . . . . . . . . . . . 20display . . . . . . . . . . . . . . . . . . . . . . . . . . . 22fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20grounding . . . . . . . . . . . . . . . . . . . . . . . . . 20I/0 key . . . . . . . . . . . . . . . . . . . . . . . . . . . 21inputs and outputs . . . . . . . . . . . . . . . . . . 21mains connection unit . . . . . . . . . . . . . . . 20on/off switch . . . . . . . . . . . . . . . . . . . . . . . 20overview . . . . . . . . . . . . . . . . . . . . . . . . . . 19soft keys . . . . . . . . . . . . . . . . . . . . . . . . . . 22status LEDs . . . . . . . . . . . . . . . . . . . . . . . 21version . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

help system . . . . . . . . . . . . . . . . . . . . . . . . . . 38hotline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 229

II/0 key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21Ial, refer to accuracy limiting secondary excitation currentI-DC parameter . . . . . . . . . . . . . . . . . . . . . . . 76Ie, refer to accuracy limiting current for IEC 60044-1 class PXIe1 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64IEC 60044-1

assessed parameters . . . . . . . . . . . . . . . 97class definition . . . . . . . . . . . . . . . . . . . . 194class P parameters . . . . . . . . . . . . . . . . . 62class PR parameters . . . . . . . . . . . . . . . . 63class PX parameters . . . . . . . . . . . . . . . . 63conditions for OK assessment . . . . . . . . 100excitation graph . . . . . . . . . . . . . . . . . . . . 85excitation test results . . . . . . . . . . . . . . . . 79parameter definition syntax . . . . . . . . . . 208parameters for meas. CTs . . . . . . . . . . . . 64

IEC 60044-6assessed parameters . . . . . . . . . . . . . . . 97class definition . . . . . . . . . . . . . . . . . . . . 193class TPS parameters . . . . . . . . . . . . . . . 65class TPS results . . . . . . . . . . . . . . . . . . 81class TPX parameters . . . . . . . . . . . . . . . 66class TPX results . . . . . . . . . . . . . . . . . . 81class TPY parameters . . . . . . . . . . . . . . . 68class TPY results . . . . . . . . . . . . . . . . . . 81class TPZ parameters . . . . . . . . . . . . 70–71class TPZ results . . . . . . . . . . . . . . . . . . . 81conditions for OK assessment . . . . . . . 100excitation graph . . . . . . . . . . . . . . . . . . . . 85excitation test results . . . . . . . . . . . . . . . . 81parameter definition syntax . . . . . . 209–210

IEC-ID field . . . . . . . . . . . . . . . . . . . . . . . . . . 57IEEE C57.13

assessed parameters . . . . . . . . . . . . . . . 97class definition . . . . . . . . . . . . . . . . . . . . 193conditions for OK assessment . . . . . . . 100excitation graph . . . . . . . . . . . . . . . . . . . . 85excitation test results . . . . . . . . . . . . . . . . 83parameter definition syntax . . . . . . . . . . 211

Ikn, refer to knee point currentI-meas parameter . . . . . . . . . . . . . . . . . . . . . 73inputs

overview . . . . . . . . . . . . . . . . . . . . . . . . . 21technical data . . . . . . . . . . . . . . . . . . . . 216

installationCPC Explorer . . . . . . . . . . . . . . . . . . . . 138CT Analyzer PC Toolset . . . . . . . . . . . . 110

instrument security factor (FS, FSi) . . . . . . . . . . . . . . . . . . . 64, 80, 84, 97

calculation . . . . . . . . . . . . . . . . . . . . . . . 179insulation coordination . . . . . . . . . . . . . . . . 219I-p parameter . . . . . . . . . . . . . . . . . . . . . . . . 91Ipn, refer to rated primary currentIsn, refer to rated secondary currentItest, refer to test current for ext. burden

Index

235

KK*Kssc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98K, refer to secondary loop time constantknee point current (Ikn) . . . . . . . . . . . 79, 81, 83knee point voltage (Vkn) . . . . . . . . . . 79, 81, 83knee point, calculation . . . . . . . . . . . . . . . . 192Kr, refer to remanence factor . . . . . . . . . . . 190Kssc, refer to rated symmetrical short-circuit current factorKtd calculation (setting) . . . . . . . . . . . . . . . . . 48Ktd*Kssc . . . . . . . . . . . . . . . . . . . . . . . . . . . . 98Ktd, refer to transient dimensioning factorK-value graph graph . . . . . . . . . . . . . . . . . . . 88Kx, refer to dimensioning factor for IEC 60044-1 class PX

Llanguage selection

CPC Explorer . . . . . . . . . . . . . . . . . . . . . 141CT Analyzer . . . . . . . . . . . . . . . . . . . . . . . 48CTA Start Page . . . . . . . . . . . . . . . . . . . 115software tools . . . . . . . . . . . . . . . . . . . . . 115

language update . . . . . . . . . . . . . . . . . . 52, 131licenses update . . . . . . . . . . . . . . . . . . . . . . . 53Lm, refer to non-saturated inductanceloading a file . . . . . . . . . . . . . . . . . . . . . . . . . 44Location field . . . . . . . . . . . . . . . . . . . . . . . . . 57Ls, refer to saturated inductance

MMain Menu . . . . . . . . . . . . . . . . . . . . . . . . . . 40

File Handling . . . . . . . . . . . . . . . . . . . . . . 44New CT test . . . . . . . . . . . . . . . . . . . . . . . 40Settings . . . . . . . . . . . . . . . . . . . . . . . . . . 48Tools . . . . . . . . . . . . . . . . . . . . . . . . . . . . 52

mains fuse . . . . . . . . . . . . . . . . . . . . . . . . . . . 20mains power supply, technical data . . . . . . 215mains socket . . . . . . . . . . . . . . . . . . . . . . . . . 20

Manufact. field . . . . . . . . . . . . . . . . . . . . . . . 58max. allowed secondary excitation current at E1 (Ie1) . . . . . . . . . . . . . . . . . 97–98maximum allowed excitation current . . . 81–82maximum allowed excitation current at E1 . . 66measurement cable set . . . . . . . . . . . . . . . 225measurement inputs

overview . . . . . . . . . . . . . . . . . . . . . . . . 216technical data . . . . . . . . . . . . . . . . . . . . 216

minimum computer requirementsfor CPC Explorer . . . . . . . . . . . . . . . . . . 138for CT Analyzer PC Toolset . . . . . . . . . 109

misc. settings . . . . . . . . . . . . . . . . . . . . . . . . 48multicore CTs

application example . . . . . . . . . . . . . . . 157

Nnavigating in file system . . . . . . . . . . . . . . . . 46NetSim export . . . . . . . . . . . . . . . . . . . . . . 137New CT test (main menu) . . . . . . . . . . . . . . 40noise reduction for measurement . . . . . . . . 158nominal burden . . . . . . . . . . . . . . . . . . . . . . 60non-saturated inductance (Lm) . . . . . 80, 82, 84

calculation . . . . . . . . . . . . . . . . . . . . . . . 192

OObject field . . . . . . . . . . . . . . . . . . . . . . . . . . 57OMICRON News service . . . . . . . . . . . . . . 114on/off switch . . . . . . . . . . . . . . . . . . . . . . . . . 20operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 35Optional field . . . . . . . . . . . . . . . . . . . . . . . . 58output

overview . . . . . . . . . . . . . . . . . . . . . . . . . 21technical data . . . . . . . . . . . . . . . . . . . . 215

overload indication . . . . . . . . . . . . . . . . . 72, 77overview, hardware overview . . . . . . . . . . . . 19

CT Analyzer

236

PP/M parameter . . . . . . . . . . . . . . . . . . . . . . . 59parameter

ALF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 62Burden . . . . . . . . . . . . . . . . . . . . . . . . 61, 73Class . . . . . . . . . . . . . . . . . . . . . . 60, 97–99Class mult. factor . . . . . . . . . . . . . . . . . . . 62Cos ϕ . . . . . . . . . . . . . . . . . . . . . . . . . 61, 73Delta compensation . . . . . . . . . . . . . . . . . 62Δϕ . . . . . . . . . . . . . . . . . . . . . . . . . . . 97–99Duty . . . . . . . . . . . . . . . . . . . . . . . . . . 66, 68ε . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97–99E1 . . . . . . . . . . . . . . . . . . . . . 64–65, 81–82εc . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97Ek . . . . . . . . . . . . . . . . . . . . . . 63, 81–82, 97ext. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64Frequency . . . . . . . . . . . . . . . . . . . . . . . . 61FS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64I-al . . . . . . . . . . . . . . . . . . . . . . . . . . . 65, 98I-DC . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Ie . . . . . . . . . . . . . . . . . . . . . . 63, 81–82, 97Ie1 . . . . . . . . . . . . . . . 64, 66, 81–82, 97–98I-kn . . . . . . . . . . . . . . . . . . . . . . . . 79, 81, 83I-meas . . . . . . . . . . . . . . . . . . . . . . . . . . . 73I-p . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91I-pn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59I-sn . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59I-test . . . . . . . . . . . . . . . . . . . . . . . . . . 72, 75K*Kssc . . . . . . . . . . . . . . . . . . . . . . . . . . . 98Kssc . . . . . . . . . . . . . . . . . 65–66, 68, 70, 82Ktd . . . . . . . . . . . . . . . . . . . . . 66, 68, 70, 82Ktd*Kssc . . . . . . . . . . . . . . . . . . . . . . . . . 98Kx . . . . . . . . . . . . . . . . . . . . . . . . . 63, 80, 97P/M . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 59Phase . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91Polarity . . . . . . . . . . . . . . . . . . . . . . . . . . . 91Ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . . 91Rct . . . . . . . . . . . . . . . . . . . . . . . . . . . 97–99RF . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71R-meas . . . . . . . . . . . . . . . . . . . . . . . . . . 76R-ref . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Standard. . . . . . . . . . . . . . . . . . . . . . . . . . 59t1, t2 . . . . . . . . . . . . . . . . . . . . . . . . . . 67–68

t-al . . . . . . . . . . . . . . . . . . . . . . . . . . . 67, 69tfr . . . . . . . . . . . . . . . . . . . . . . . . . . . . 67, 69T-meas . . . . . . . . . . . . . . . . . . . . . . . . . . 75Tp . . . . . . . . . . . . . . . . . . . . . 65–66, 68, 70T-ref . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76Ts . . . . . . . . . . . . . . . . . . . . . . . . 63, 68, 70VA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60V-al . . . . . . . . . . . . . . . . . . . . . . . . . . 65, 98Vb . . . . . . . . . . . . . . . . . . . . . . . . . . . 70, 84V-DC . . . . . . . . . . . . . . . . . . . . . . . . . . . . 76V-kn . . . . . . . . . . . . . . . . . . . . . . . 79, 81, 83V-meas . . . . . . . . . . . . . . . . . . . . . . . . . . 73Z . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 73

parameter definition syntax . . . . . . . . . . . . 207pasting a file . . . . . . . . . . . . . . . . . . . . . . . . . 47PC Toolset . . . . . . . . . . . . . . . . . . . . . . . . . 109PDF manual . . . . . . . . . . . . . . . . . . . . . . . . . 10peak instantaneous error (ε-peak) . . . . . 83, 98

calculation . . . . . . . . . . . . . . . . . . . . . . . 187permissible time to accuracy (tal) . . . . . . 67, 69phase accuracy . . . . . . . . . . . . . . . . . . . . . 217phase deviation ε . . . . . . . . . . . . . . . . . . 97–99phase error . . . . . . . . . . . . . . . . . . . . . . . . . . 91Phase field . . . . . . . . . . . . . . . . . . . . . . . . . . 57Phase parameter . . . . . . . . . . . . . . . . . . . . . 91phase table . . . . . . . . . . . . . . . . . . . . . . . . . . 92

accuracy of values . . . . . . . . . . . . . . . . 217polarity

ok / not ok . . . . . . . . . . . . . . . . . . . . . . . . 91power supply . . . . . . . . . . . . . . . . . . . . 12, 215primary time constant (Tp) . . . . . 65–66, 68, 70

Qqualification of operating personnel . . . . . . . 11QuickTest software . . . . . . . . . . . . . . . . . . 116

Index

237

Rrated equivalent excitation limiting secondary voltage (Val) . . . . . . . . . . . . . . 65, 98rated knee point emf (Ek) . . . . . . . . . . . . . . . 97rated primary current (Ipn) . . . . . . . . . . . . . . . 59rated secondary current (Isn) . . . . . . . . . . . . . 59rated secondary terminal voltage . . . . . . 70, 84rated secondary terminal voltage acc. to IEEE C57.13 (VB) . . . . . . . . . . . . . . . . . . . . . 99

calculation . . . . . . . . . . . . . . . . . . . . . . . 189rated symmetrical short-circuit current factor (Kssc) . . . . . . . . . . . . . . 65–66, 68, 70, 82

calculation . . . . . . . . . . . . . . . . . . . . . . . 187ratio accuracy . . . . . . . . . . . . . . . . . . . . . . . 217Ratio card . . . . . . . . . . . . . . . . . . . . . 33, 35, 90

accuracy of phase table values . . . . . . . 217accuracy of ratio table values . . . . . . . . 217available soft keys . . . . . . . . . . . . . . . . . . 90phase table . . . . . . . . . . . . . . . . . . . . . . . 92ratio table . . . . . . . . . . . . . . . . . . . . . . . . . 92settings . . . . . . . . . . . . . . . . . . . . . . . . . . 91test results . . . . . . . . . . . . . . . . . . . . . . . . 91

ratio correction factorcalculation . . . . . . . . . . . . . . . . . . . . . . . 178

ratio error . . . . . . . . . . . . . . . . . . . . . . . . . . . 91calculation . . . . . . . . . . . . . . . . . . . . . . . 175

ratio measurement . . . . . . . . . . . . . . . . . . . . 33Ratio parameter . . . . . . . . . . . . . . . . . . . . . . 91ratio table . . . . . . . . . . . . . . . . . . . . . . . . . . . 92

accuracy of values . . . . . . . . . . . . . . . . . 217RCF

calculation . . . . . . . . . . . . . . . . . . . . . . . 178Rct . . . . . . . . . . . . . . . . . . . . . . . . . . . 61, 97–99reference graph . . . . . . . . . . . . . . . . . . . . . . . 86remanence factor (Kr) . . . . . . 81–82, 84, 97–99

calculation . . . . . . . . . . . . . . . . . . . . . . . 190remanent flux (Ψr) . . . . . . . . . . . . . . . . . . . . 191Remote Control software . . . . . . . . . . . . . . 136Remote Excel File Loader . . . . . . . . . . . . . . 123renaming a file . . . . . . . . . . . . . . . . . . . . . . . 44reset to factory calibration . . . . . . . . . . . . . . . 53

Resistance card . . . . . . . . . . . . . . . . 32, 35, 75accuracy of winding resistance values . 216test results . . . . . . . . . . . . . . . . . . . . . . . . 76test settings . . . . . . . . . . . . . . . . . . . . . . . 75

resistance measurement . . . . . . . . . . . . . . . 32R-meas parameter . . . . . . . . . . . . . . . . . . . . 76R-ref parameter . . . . . . . . . . . . . . . . . . . . . . 76running the burden test . . . . . . . . . . . . . . . . 73

Ssafety

changing fuses . . . . . . . . . . . . . . . . . . . . 13power supply . . . . . . . . . . . . . . . . . . . . . . 12qualification of operating personnel . . . . 11safe operation . . . . . . . . . . . . . . . . . . . . . 11safety instructions . . . . . . . . . . . . . . . . . . 10safety rules . . . . . . . . . . . . . . . . . . . . . . . 13

safety standards . . . . . . . . . . . . . . . . . . . . . 222sample software for CTA Remote Control . 136saturated inductance (Ls) . . . . . . . . . 80, 82, 84

calculation . . . . . . . . . . . . . . . . . . . . . . . 191saturation flux (Ψs) . . . . . . . . . . . . . . . . . . . 190saving a file . . . . . . . . . . . . . . . . . . . . . . . . . 47scope of delivery . . . . . . . . . . . . . . . . . . . . 223second. loop time constant (Ts) . . . . . . . . . . . . . . 63, 68, 70, 81–82, 84, 97–99

calculation . . . . . . . . . . . . . . . . . . . . . . . 188Serial No field . . . . . . . . . . . . . . . . . . . . . . . . 58Settings (main menu) . . . . . . . . . . . . . . . . . . 48

available functions . . . . . . . . . . . . . . . . . . 48soft keys . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

using the soft keys . . . . . . . . . . . . . . . . . 36software

version of CPC Explorer software . . . 2, 138version of CT Analyzer PC Toolset . . 2, 112version of CT Analyzer software . . . . . 2, 38

standard (default setting) . . . . . . . . . . . . . . . 48Standard (parameter) . . . . . . . . . . . . . . . . . . 59start page

CT Analyzer PC Toolset . . . . . . . . . . . . 111starting a test . . . . . . . . . . . . . . . . . . . . . . . . 32

CT Analyzer

238

SStation field . . . . . . . . . . . . . . . . . . . . . . . . . . 57status LEDs . . . . . . . . . . . . . . . . . . . . . . . . . . 21stylesheet

in CPC Explorer . . . . . . . . . . . . . . . 140–141symbols used in manual . . . . . . . . . . . . . . . . . 9system information . . . . . . . . . . . . . . . . . . . . 38system requirements

for CPC Explorer . . . . . . . . . . . . . . . . . . 138for CT Analyzer PC Toolset . . . . . . . . . . 109

Tt1, t2, refer to duration of current flowtal, refer to permissible time to accuracyTap field . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58tapped CTs

application example . . . . . . . . . . . . . . . . 154technical data

Compact Flash card . . . . . . . . . . . . . . . . 220electromagnetic compatibility . . . . . . . . . 221environmental conditions . . . . . . . . . . . . 221inputs . . . . . . . . . . . . . . . . . . . . . . . . . . . 216insulation coordination . . . . . . . . . . . . . . 219mains power supply . . . . . . . . . . . . . . . . 215output . . . . . . . . . . . . . . . . . . . . . . . . . . . 215phase accuracy . . . . . . . . . . . . . . . . . . . 217ratio accuracy . . . . . . . . . . . . . . . . . . . . 217safety standards . . . . . . . . . . . . . . . . . . 222weight and dimensions . . . . . . . . . . . . . 222winding resistance accuracy . . . . . . . . . 216

technical support . . . . . . . . . . . . . . . . . . . . . 229temperature unit (selection) . . . . . . . . . . . . . 48terminal adapters . . . . . . . . . . . . . . . . . . . . 225test cards

available cards . . . . . . . . . . . . . . . . . . . . . 35dependencies . . . . . . . . . . . . . . . . . . . . . 50displaying a specific card . . . . . . . . . . . . . 36editing a card . . . . . . . . . . . . . . . . . . . . . . 37

test cards (default setting) . . . . . . . . . . . . . . . 48test current for ext. burden (Itest) . . . . . . . . . . 72

test current for winding resistance (Itest) . . . 75test settings . . . . . . . . . . . . . . . . . . . . . 56, 126T-meas parameter . . . . . . . . . . . . . . . . . . . . 75Tools (main menu) . . . . . . . . . . . . . . . . . . . . 52

available soft functions . . . . . . . . . . . . . . 52reset to factory calibration . . . . . . . . . . . . 53update firmware . . . . . . . . . . . . . . . . . . . 52update licenses . . . . . . . . . . . . . . . . . . . . 53update text . . . . . . . . . . . . . . . . . . . . . . . 52

Tp, refer to primary time constanttransient dim. factor (Ktd) . . . . . . 66, 68, 70, 82

determination . . . . . . . . . . . . . . . . . . . . 196transport case . . . . . . . . . . . . . . . . . . . . . . 225T-ref parameter . . . . . . . . . . . . . . . . . . . . . . 76TS, refer to secondary loop time constantturns ratio . . . . . . . . . . . . . . . . . . . . . . . . . . . 91turns ratio error (εt) . . . . . . . . . . . . . . 92, 97–98

calculation . . . . . . . . . . . . . . . . . . . . . . . 177Type field . . . . . . . . . . . . . . . . . . . . . . . . . . . 58

UUal, refer to rated equivalent excitation limiting secondary voltageunwound core

application example . . . . . . . . . . . . . . . 156update firmware . . . . . . . . . . . . . . . . . . . . . . 52update licenses . . . . . . . . . . . . . . . . . . . . . . 53update text . . . . . . . . . . . . . . . . . . . . . . . . . . 52user interface

description . . . . . . . . . . . . . . . . . . . . . . . . 35language update . . . . . . . . . . . . . . . 52, 131working with the UI . . . . . . . . . . . . . . . . . 36

user-defined code in CTA Remote Excel File Loader . . . . . . . . . . . . . . . . . . . . . . . . . . . . 129user-defined emf . . . . . . . . . . . . . . . 65, 81–82

Index

239

VVA parameter . . . . . . . . . . . . . . . . . . . . . . . . 60Val, refer to rated equivalent excitation limiting secondary voltageVB, refer to rated secondary terminal voltage acc. to IEEE C57.13V-DC parameter . . . . . . . . . . . . . . . . . . . . . . 76version

CPC Explorer software . . . . . . . . . . . . . . . 2CT Analyzer software . . . . . . . . . . . . . 2, 38hardware . . . . . . . . . . . . . . . . . . . . . . . . . 38language . . . . . . . . . . . . . . . . . . . . . . . . . 38

Vkn, refer to knee point voltageV-meas parameter . . . . . . . . . . . . . . . . . . . . 73

Wwarning messages . . . . . . . . . . . . . . . . . . . 163weight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222winding resistance . . . . . . . . . . . . . . 61, 97–99winding resistance accuracy . . . . . . . . . . . . 216wiring diagrams . . . . . . . . . . . . . . . . . . . . . . . 38wiring for burden test . . . . . . . . . . . . . . . . . . 25wiring for CT test . . . . . . . . . . . . . . . . . . . . . . 26

4 wire connection technique . . . . . . . . . . 28wye winding transformer

application example . . . . . . . . . . . . . . . . 147

ZZ parameter . . . . . . . . . . . . . . . . . . . . . . . . . 73

CT Analyzer

240

CT Analyzer User Manual - User Equip: New & Used Test...

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