GE Feeder Management Relay 750 User Manual

GE Multilin 750/760 Feeder Management Relay 8-37
8 COMMISSIONING TESTS 8.5 MONITORING
8
5. Now reduce V
an
until the VT Failure condition returns. Verify the ratio of the negative sequence voltage (V
2
) to the pos-
itive sequence voltage (V
1
) is 0.25 at this point. Return V
an
to nominal and the VT Failure condition should reset.
Repeat this step for V
bn
and V
cn
.
6. With V
an
= V
bn
= V
cn
returned to nominal voltage at 0°, 120°, and 240° respectively, reduce V
an
until the VT Failure
condition returns. Now reduce Ia until the VT Failure condition resets. Verify the ratio of the negative sequence current
(I
2
) to the positive sequence current (I
1
) > 0.20 at this point. Return I
a
to nominal and the VT Failure condition should
reset. Repeat this step for I
b
and I
c
.
8.5.8 TRIP COIL MONITOR
The Indications and Operations for the Trip Coil Monitor are as outlined for Phase TOC 1 on page 8–16, except that this
element has no Trip function.
1. Ensure the wiring to the circuit breaker trip and close circuits is complete.
2. Energize the breaker trip and close circuits and close the breaker.
3. Carefully disconnect a wire to open the trip circuit. After 5 seconds the element should generate an output.
4. Restore the open circuit and the element should reset.
5. If the Open Breaker permissive is "Enabled", and the trip circuit wiring has been arranged to permit this operation,
open the breaker.
6. Repeat Steps 3 and 4.
8.5.9 CLOSE COIL MONITOR
The Indications and Operations for the Close Coil Monitor are as outlined for Phase TOC 1 on page 8–16, except that this
element has no Trip function.
1. Ensure the wiring to the circuit breaker trip and close circuits is complete.
2. Energize the breaker trip and close circuits and open the breaker.
3. Carefully disconnect a wire to open the close circuit. After 5 seconds the element should generate an output.
4. Restore the open circuit and the element should reset.
5. If the Closed Breaker permissive is "Enabled", and the close circuit wiring has been arranged to permit this operation,
close the breaker.
6. Repeat Steps 3 and 4.
8.5.10 BREAKER OPERATION FAILURE
The Indications and Operations for the Breaker Operation Failure are as outlined for Phase TOC 1 on page 8–16, except
that this element has no Trip function.
1. Ensure the wiring to the circuit breaker trip and close circuits is complete.
2. Energize the breaker trip and close circuits and open the breaker.
3. Carefully disconnect a wire to open the close circuit. Apply a momentary Close command to the relay. After a delay the
element should generate an output (the delay time can be checked in the Event Recorder).
4. Restore the open circuit and reset the relay.
5. Close the breaker.
6. Carefully disconnect a wire to open the trip circuit. Apply a momentary Trip command to the relay. After a delay the ele-
ment should generate an output (the delay time can be checked in the Event Recorder)
7. Restore the open circuit and reset the relay.
8. Open and close the breaker a number of times to confirm the delay time provides sufficient margin to allow for normal
operation of the breaker.
Courtesy of NationalSwitchgear.com

GE Feeder Management Relay 750 Specifications

General

Brand	GE
Model	Feeder Management Relay 750
Category	Protection Device
Language	English