GE 350-A9

6–72 350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
S3 PROTECTION CHAPTER 6: SETPOINTS
Figure 6-30: Negative sequence instantaneous overcurrent protection logic diagram
Calculated Negative
Sequence Current
SETPOINTS
SETPOINT
NEG SEQ IOC FUNCTN: Disabled = 0
Latched Alarm
NEG SEQ IOC PICKUP:
AND
Operate Output Relay 1 (TRIP)
Event Recorder
Transient Recorder
LED: TRIP
Alarm
OR
OR
AND
SETPOINTS
Do Not Operate, Operate OUTPUT RELAY X
Trip
AND
To Breaker Failure
Trip
SETPOINTS
BLOCK 1: Off = 0 BLOCK 2: Off = 0 BLOCK 3: Off = 0
OR
RUN
LED: PICKUP
Event Recorder
Transient Recorder
NegSeq IOC
Message
I_2 > PICKUP
NEG SEQ IOC DELAY:
SETPOINT
t
PKP
I_2
LED: ALARM
RESET
Command
AND
S R
LATCH
0
898795A1.cdr