GE 889 - Page 283

CHAPTER 4: SETPOINTS PROTECTION
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL 4–153
Figure 4-54: Offline Overcurrent Logic Diagram
SETPOINTS
Phase A current (Ia)
RUN
SETPOINTS
FUNCTION: Disabled = 0 Trip
PICKUP:
AND
Phase B current (Ib) Phase C current (Ic)
RUN RUN
Operate Output Relay 1 (TRIP)
LED: PICKUP
Alarm
OR
OR
AND
Latched Alarm
AND
BLOCK Off = 0
Ib > PICKUP Ia > PICKUP Ic > PICKUP
SETPOINTS
t
PKP
t
PKP
t
PKP
OR
OR
LED: ALARM
RESET
Command
AND
S R
LATCH
Configurable
Offline OC OP
Offline OC OP A Offline OC OP B Offline OC OP C
FlexLogic Operands
Offline OC PKP
Offline OC PKP A Offline OC PKP B Offline OC PKP C
FlexLogic Operands
SETPOINTS
OUTPUT RELAYS 2 to X Do Not Operate, Operate
0 0 0
PICKUP DELAY:
LED: TRIP
Set
Dominant
SETPOINTS
Signal Input
SETPOINTS
AND AND
OFFLINE
FlexLogic Operand
CT BANK 1-J1 CT BANK 1-K1
TRIPPED
FlexLogic Operand
OR
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