Microprocessor Based Overload Relay 3RB12

Automation and Drives

Low VoltageControls & Distribution

Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Microprocessor based Relays

Type 3RB12

Introduction



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Range - 3RB12

3 Control voltages:110-120 V AC220-230 V AC24 V DC

6 Ranges from 1.25A to 820A

3RB12 46 1P… 1.25A to 6.3A

3RB12 46 1P… 6.3A to 25A

3RB12 46 1P… 25A to 100A

3RB12 53 0F… 50A to 205A

3RB12 57 0K… 125A to 500A

3RB12 62 0L… 200A to 820A

Range



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Block diagram of internal construction

Micro-Processor

• Overload• Phase failure• Current unbalance• Thermistor monitoring• Ground fault monitoring• Self monitoring

Status memory

e.g. Overload/Thermistor trip:Output relay 1NO/1NC

e.g. Ground fault trip:Output relay 1NO/1NC

Summation CT

Thermistor connection

Hand/Remote/Auto-RESET

Test function

Set class

Set Ie

Integrated CT's

Motor current

Rectification

A/D-converter

Power supply

Control supply voltage

Self monitoring:Continuous

green LED "Ready"

Overload warning:Flashing

red LED "Overload"

Overload Thermistortrip: Continuous

red LED "Overload"

Ground fault:Continuous

red LED "Ground Fault"

Functions

Functions



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

A B

Device test,Hand-Reset

Selection of the trippingclasses: class 5 to 30

Ie setting, only three versions for the ranges from 1.25 A to 100 A

Connection for a thermistorsensor circuit for fullmotor protection

Control supplyvoltage connections

3 LED indicators

1NO+1NC for overloadtripping by currentand/or thermistor

1 NO+1 NC for groundfault tripping

Either Handreset (withTest-/Reset-button), remote or automatic reset

Connection for an external summation CTfor ground fault monitoring

Layout

Layout



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Push-through main conductors ondevices with setting current rangeup to 100 A

The setting current range below 1.25 A is covered by looping the main conductors through the transducer (e.g. 3 loops for the range 0.42 A to 0.62 A)

No extra connection effort

No power loss in contact resistance

No failure / nuisance trip due to loose termination

Features

Features

Push-through technique



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Monitoring of the current for overload, asymmetry and loss of phase by Lock rotor having CT in each of the three phases.

3RB12e110.ppt/10.97

120100

50

20

10

5

21

50

20

10

5

2

10.7 1 2 5 8

100

50

20

10

5

21

50

20

10

5

2

10.7 1 2 5 8

CLASS 30CLASS 25CLASS 20CLASS 15CLASS 10CLASS 5

CLASS 30CLASS 25CLASS 20CLASS 15CLASS 10CLASS 5

t t

x Ie x Ie

120

Tripping curves for 2 poleasymmetrical loading

Tripping curves for 3 polesymmetrical loading

Features

Features

Tripping characteristics



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

LED's direct on the unit:

Ready

Overload-trip/Thermistor-trip

Overload warning

Ground fault -trip

Externally with the NO / NC contacts:

Overload-trip / Thermistor-trip

Overload warning

Ground fault-trip

Diagnostics

Features

Display and Signals



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Pressing the Test button:

• By pressing the test/reset button on the unit the current monitoring, thermistor and ground fault protection functions and LEDs can be checked. This test can be carried out during operation. (The contactor does not trip)

• If the Test/Reset button is pressed for more than 5 seconds then the trip functions of the signaling contacts are tested.

• A function test of the unit can be carried out at any time and is simple to effect.

Pressing the Test button:

• By pressing the test/reset button on the unit the current monitoring, thermistor and ground fault protection functions and LEDs can be checked. This test can be carried out during operation. (The contactor does not trip)

• If the Test/Reset button is pressed for more than 5 seconds then the trip functions of the signaling contacts are tested.

• A function test of the unit can be carried out at any time and is simple to effect.

Diagnostics

Diagnostics



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

L1L2L3

M3~

Connection of a PTC thermistor sensor circuit:

- The actual temperature in the motor winding is monitored

Needed with:- Motors whose stator is the critical

component- Motors with impeded cooling- Plated motor surface- Motors with long starting and braking

PTB-approval

Open circuit-proof

No additional evaluation unit required

Connection of a PTC thermistor sensor circuit:

- The actual temperature in the motor winding is monitored

Needed with:- Motors whose stator is the critical

component- Motors with impeded cooling- Plated motor surface- Motors with long starting and braking

PTB-approval

Open circuit-proof

No additional evaluation unit required

Protection

Protection Functions

Full motor protection(overload + thermistor protection)



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

L1L2L3N

M3~

Internally for motors with 3- wire connection

- ground fault monitoring with fault currents > 30% of the set current Ie

Externally for motors with 3 and 4 wire connections byconnection of a 3UL22 summation CT

- reliable earth fault monitoring with fault currents of 0.3A, 0.5A and 1A

1NO/1NC as separate outputs

- the fault can either be signaled on used to switch off the motor, independent of the overload protection.

Internally for motors with 3- wire connection

- ground fault monitoring with fault currents > 30% of the set current Ie

Externally for motors with 3 and 4 wire connections byconnection of a 3UL22 summation CT

- reliable earth fault monitoring with fault currents of 0.3A, 0.5A and 1A

1NO/1NC as separate outputs

- the fault can either be signaled on used to switch off the motor, independent of the overload protection.

Protection

Protection Functions

Ground fault monitoring



Introduction

Functions

Layout

Features

Diagnostics

Range

Protection

Applications

May‘2003A&D CD-BD

Applications

Chemical industries.

Paper/Plastics industries.

Steel Plant.

Water supplies.

Gas converting.

Paint plants......

Applications

High demand applications such as

Microprocessor Based Overload Relay 3RB12

Documents

Transcript of Microprocessor Based Overload Relay 3RB12