Trip Coil Monitor; Close Coil Monitor; Breaker Operation Failure - GE 750 Instruction Manual

Monitoring

Trip Coil Monitor

Close Coil Monitor

Breaker Operation
Failure
GE Multilin
1. Set V = V = V = nominal voltage at 0°, 120°, and 240° respectively, and
an bn cn
inject into the relay. With these balanced voltages 120° apart, the positive
sequence voltage (V ) is greater than 0.05 x VT.
1
2. Set I = I = I = 1 x CT at 0°, 120°, and 240° respectively, and inject into the
a b c
relay. With these balanced currents 120° apart, the positive sequence current
(I ) is greater than 0.05 x CT.
1
3. Remove the balanced voltages so the positive sequence voltage (V
0.05 x VT. If this function is set to "Control", any output relays programmed for
this condition should operate. If the function is set to "Alarm", check that the
Alarm and Message LEDs are flashing, the VT Failure alarm message is
displayed, and any output relays programmed for this condition are operated.
4. Apply the balanced voltages and the VT Failure condition should reset.
5. Now reduce V until the VT Failure condition returns. Verify the ratio of the
an
negative sequence voltage (V
this point. Return V
an
Repeat this step for V
bn
6. With V = V = V
an bn cn
respectively, reduce V
an
until the VT Failure condition resets. Verify the ratio of the negative sequence
current (I ) to the positive sequence current (I
2
to nominal and the VT Failure condition should reset. Repeat this step for I
I .
c
The Indications and Operations for the Trip Coil Monitor are as outlined for Phase
TOC 1 on page 7–18, 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.
The Indications and Operations for the Close Coil Monitor are as outlined for Phase
TOC 1 on page 7–18, 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.
The Indications and Operations for the Breaker Operation Failure are as outlined for
Phase TOC 1 on page 7–18, 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).
http://www.GEmultilin.com
) to the positive sequence voltage (V
2
to nominal and the VT Failure condition should reset.
and V .
cn
returned to nominal voltage at 0°, 120°, and 240°
until the VT Failure condition returns. Now reduce Ia
) > 0.20 at this point. Return I
1
750/760
Feeder Management Relay
) is less than
1
) is 0.25 at
1
a
and
b
7–41