GE Multilin 350 Series - Page 205

CHAPTER 6: SETPOINTS S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 6–89
Figure 26: 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
Operate
output relays
upon
selection
OUTPUT RELAY
4
OUTPUT RELAY
5
OUTPUT RELAY
6
OUTPUT RELAY
3
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
898795.cdr
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