GE Multilin 350 Series

CHAPTER 6: SETPOINTS S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 6–83
Figure 23: Neutral Instantaneous Overcurrent Protection: Logic Diagram
SETPOINT
Neutral current (IN)
RUN
SETPOINT
BLOCK 1: Off=0
NTRL IOC PICKUP:
IN > PICKUP
BLOCK 2: Off=0 BLOCK 3: Off=0
OR
AND
Operate Output Relay 1 (TRIP)
Event Recorder
Transient Recorder
LED: TRIP
OR
OR
Cold Load PKP
Autoreclose
(per shot settings)
Computed by the relay
Block Inputs
AND
SETPOINT:
Operate
output relay
upon
selection
OUTPUT RELAY 4 OUTPUT RELAY 5 OUTPUT RELAY 6 OUTPUT RELAY 3
AND
SETPOINT
NTRL IOC DIRECTN:
Forward Disabled Reverse
SETPOINT
NTRL IOC FUNCTION:
Disabled = 0
Latched Alarm Alarm
Trip
AND AND
Current in Reverse
From NEUTRAL DIRECTIONAL
Current OK
NTRL IOC PKP DLY:
SETPOINT
t
PKP
0
Event Recorder
Transient Recorder
LED: ALARM
RESET
Command
AND
S
R
LATCH
LED: PICKUP
Neutral IOC PKP
Message:
Neutral IOC OP
898007.cdr
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