GE 750 - Page 467

GE Power Management 750/760 Feeder Management Relay 17-
61
17 COMMISSIONING 17.9 CONTROL SCHEMES
17
3. Inject V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
4. Reduce the injected voltages to cause an undervoltage trip, then set
V
bn
and V
cn
to 0
5. Slowly raise
V
an
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
an
.
6. Repeat steps 3 through 5 except adjust
V
bn
and V
cn
in turn.
Procedure To Check Minimum Voltage with Two Phases For Operation:
1. Assert or De-assert a logic input to simulate an open breaker.
2. Set Undervolt Restore Delay to 0.
3. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
4. Reduce the injected voltages to cause an undervoltage trip, then set V
bn
to 0 and V
cn
to nominal.
5. Slowly raise
V
an
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
an
with V
cn
.
6. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
7. Reduce the injected voltages to cause an undervoltage trip, then set
V
cn
to 0 and V
bn
to nominal.
8. Slowly raise
V
an
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
an
with V
bn
.
9. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
10. Reduce the injected voltages to cause an undervoltage trip, then set
V
cn
to 0 and V
an
to nominal.
11. Slowly raise
V
bn
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
bn
with V
an
.
12. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
13. Reduce the injected voltages to cause an undervoltage trip, then set
V
an
to 0 and V
cn
to nominal.
14. Slowly raise
V
bn
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
bn
with V
cn
.
15. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
16. Reduce the injected voltages to cause an undervoltage trip, then set
V
an
to 0 and V
bn
to nominal.
17. Slowly raise
V
cn
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
cn
with V
bn
.
18. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
19. Reduce the injected voltages to cause an undervoltage trip, then set
V
bn
to 0 and V
an
to nominal.
20. Slowly raise
V
cn
until the 2 CLOSE relay operates. This is the operating level of setpoint
UNDERVOLT
RESTORE MIN VOLTS
for V
cn
with V
an
.
Procedure To Check Minimum Voltage with Three Phases For Operation:
1. Assert or De-assert a logic input to simulate an open breaker.
2. Set Undervolt Restore Delay to 0.
3. Inject
V
an
= V
bn
= V
cn
= nominal voltage into the bus voltage input of the relay.
4. Reduce the injected voltages to cause an undervoltage trip, then set
V
an
and V
cn
to nominal.