FIELD TESTING LC OPTICAL FIBER SYSTEMS

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TABLE of CONTENTS

INTRODUCTION ......................................................................................................................................3 TESTING WITH DUAL SOURCES AND DETECTORS ...........................................................................4

Step 1: ................................................................................................................................... 4 Step 2: ................................................................................................................................... 5 Step 3: ................................................................................................................................... 6 Step 4: ................................................................................................................................... 6 Step 5: ................................................................................................................................... 7 Step 6: ................................................................................................................................... 7

CONCLUSION .........................................................................................................................................7 LC TEST KITS PART NUMBERS ARE BASED ON FIBER TYPE AND TEST METER PORTS ..........8

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INTRODUCTION This paper describes field testing procedures for LC optical fiber systems. TIA/EIA-568, Commercial Building Telecommunications Cabling Standard, currently recommends the one jumper reference method. This procedure is described in TIA/EIA-526-14A, Method B, Optical Power Loss Measurements of Installed Multimode Fiber Cable Plant, and TIA/EIA-526-7, Method A1, Measurement of Optical Power Loss of Installed Single-mode Fiber Cable Plant.

To ensure accurate and repeatable test results, the test jumpers used during the test must be of good quality and be clean (no end face debris). More often than not, high losses experienced during testing are a result of poor quality test jumpers. If there is doubt about the cable assembly, or if test results are erratic or unusually high, replace the cable assembly before conducting any testing. Note: Replacing assemblies once a reference value has been obtained requires a new reference measurement before further testing is completed.

Tyco Electronics offers AMP NETCONNECT test kits comprised of quality jumpers in the proper configurations and fiber types for use with SC, ST, or LC transmit and with LC receive interface test equipment. These test kits are available to test either standard LC or Tyco Electronics AMP NETCONNECT LC SECURE systems. Additionally, individual jumpers are available for replacement if they become damaged or worn after repeated use.

Another important factor in obtaining accurate and repeatable results is the launch condition of the source. TIA/EIA-568, ISO 11801 and Tyco Electronics all recognize the importance of a conditioned launch, and thus recommend the use of mandrel wraps during the reference measurement and the actual test when testing multimode fiber cabling. As stated in TIA/EIA-568, multimode optical fiber may appear to have higher than expected attenuation due to the power loss in the high-order modes. To remove the effects of these high-order mode transient losses, the transmit side of the reference jumper should be wrapped in five non-overlapping turns around a smooth mandrel during the reference calibration and for all loss measurements. The mandrel diameter depends on the fiber core size and also the referenced standard. Illustrations of proper mandrel wrap usage are shown below. Maintain this mandrel wrap during the reference and the test using a cable tie through the center hole of the mandrel and around the wrapped cable. Ensure that the cable tie is not tightened to the point of compressing the jumper cable jacket.

Note: Mandrels are not required for single-mode testing.

50/125 Fiber Tested to the IEC Standard 50/125 Fiber Tested to the TIA Standard

62.5/125 Fiber Tested to IEC or TIA Standard

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TESTING WITH DUAL SOURCES AND DETECTORS The procedure below assumes the test equipment has a transmit (Tx) SC, ST or LC port (depending on the fixed fiber adapter on the transmit port of the meter) and a receive (Rx) LC port on each unit. The illustrations assume there is a transmit SC port. Each test set manufacturer may have different features and procedures for storing references, so consult the test equipment manual for details.

Note: AMP NETCONNECT XG 50-micron (850nm laser-optimized 50/125m multimode fiber) test kits and test leads are for standard 50-micron and 850nm laser-optimized 50/125m multimode fiber (XG)

testing.

For all steps, record power values in dBm and make sure the jumper fiber type (50-micron, 62.5-micron, or single-mode) matches that of the system under test. Once a system reference measurement has been taken, do not disconnect the connectors from the transmit ports. Note: Disconnecting the transmit (Tx) ports will requires a new reference measurement (repeat step 1).

Step 1: The first step of this procedure acquires a system reference. Verify the two assemblies are clean and in good condition. For multimode testing, position the correct mandrel near the transmit connector (Tx) and apply five non-overlapping cable wraps.

Connect the (SC) connectors to the Transmit (Tx) side and the LC connectors to the Receive (Rx) side of the test meters. Record two power values as R1 and R2 - one for each fiber in the correct direction. These values are the reference values for subsequent testing.

LC SC LC SC

Tx Rx

Tx Rx

Reference Measurement

Mandrel on Transmit side for Multimode Fiber

SC Port on Tx

Mandrel on Transmit side for Multimode Fiber

SC Port on Tx LC Port on Rx LC Port on Rx

Connector Type is Determined by Fixed

Tx Port on Meter

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Step 2:

Disconnect the LC connectors from the test equipment receive ports (Rx).

SC SC

LC

LC

Tx Rx

Tx Rx

Do Not Remove (SC) Connectors from Transmit (Tx) Ports

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Step 3:

Connect one end of an LC to LC assembly (3rd assembly) to the receive (Rx) port of one test meter and one end of another LC to LC assembly (4th assembly) to the receive (Rx) port of the other test meter.

Clip the two unconnected LC connectors from each test meter with a duplex LC clip, making sure to position them so that the test meter Receive (Rx) port is placed in Position A of the clip. This will ensure the test meter Transmit (Tx) port is placed in Position B of the clip.

Step 4:

Connect the clipped LC connectors to the fiber link under test. Record two power values, P1 and P2 - one for each fiber in the correct direction.

Clip Position A

Clip Position B

Clip Position B

Clip Position A

SC LC SC LC

Installed System

under Test

Tx Rx

Tx Rx

Rx

Tx Tx Rx

LC Connectors with Duplex Clip

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Step 5: Calculate system loss (Psystem) for each direction (each fiber) by subtracting the system power values (P1 and P2) from the system reference values (R1 and R2) from step 1. Record one Psystem power value for each fiber to get two Psystem values for each duplex link.

P1system = R1 - P1 (one direction) P2system = R2 - P2 (other direction)

Step 6: Calculate the maximum allowable system loss by summing the maximum cable attenuation, maximum connector attenuation and maximum splice loss for the link under test.

P system max = Loss cable max + Loss connector max + Loss splice max

Where:

Loss cable max = Cable Attenuation Coefficient [dB/km] Cable Length [km]

Maximum Attenuation Coefficient for Cable 3.5 dB/km @ 850 nm for multimode (50/125 and 62.5/125) 1.5 dB/km @ 1300 nm for multimode (50/125 and 62.5/125) for TIA 568 1.0 dB/km @ 1300 nm for multimode (50/125 and 62.5/125) for ISO 11801 0.5 dB/km @ 1310 nm for single-mode outside plant cable 0.5 dB/km @ 1550 nm for single-mode outside plant cable 1.0 dB/km @ 1310 nm for single-mode inside plant cable 1.0 dB/km @ 1550 nm for single-mode inside plant cable

Loss connector max = Number of Connector Pairs 0.75 dB

Loss splice max = Number of Splices 0.3 dB

Note: To be eligible for the 25-year warranty, the system loss calculated in Step 5 must be less than or equal to the maximum allowable system loss published in the current Tyco Electronics AMP NETCONNECT Performance Warranty.

CONCLUSION The procedure described tests LC system link attenuation and verifies polarity using common test equipment interface connections.

The key to testing LC SECURE product is the use of universal LC test assemblies. These assemblies will connect to any color LC SECURE adapter as well as standard (non-SECURE) LC adapters. A list of test kits follows.

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LC TEST KITS PART NUMBERS ARE BASED ON FIBER TYPE AND TEST METER PORTS Note: 50-micron test kits use XG fiber these kits are appropriate for testing standard 50-micron or XG (850nm laser-optimized 50-micron) fiber links

50um and 50um XG Multimode

(See Note Above)

62.5um Multimode Single-mode Comments

1828867-1 1828868-1 1828869-1 For Use with Dual Fiber

Testers with SC Transmit Ports and LC Receive

Ports

1828867-2 1828868-2 1828869-2 For Use with Dual Fiber

Testers with ST Transmit Ports and LC Receive

Ports

LC Standard System Test Kits

1828867-3 1828868-3 1828869-3 For Use with Dual Fiber

Testers with LC Transmit Ports and LC Receive

Ports

LC SECURE System Test Kits

Contact AMP NETCONNECT Customer Service or your local Sales Engineer for the Correct Part Numbers Specific to Your Installation

LC Standard Test Kit Replacement Parts

*50um and 50um XG Multimode 62.5um Multimode Single-mode

Comments

Mandrels 1435119-1 14351181 N/A Transmit Side Only LC Duplex Clips

1754371-2 6 clips

SC to LC Simplex Assembly 1907490-3 1907491-3 1907489-3

ST to LC Simplex Assembly 1907493-3 1907494-3 1907492-3

LC to LC Simplex Assembly 1907496-3 1907497-3 1907495-3

3 meters

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In the U.S.1-800-553-0938 Canada 905-475-6222 Mexico 525-729-0400 South and Central Americas 54-11-4733-2200 www.amp.com/networking E-mail: networking.help@tycoelectronics.com

Copyright 2007 Tyco Electronics Corporation. All rights reserved. AMP, AMP NETCONNECT, NETCONNECT and Tyco are trademarks.