GE 350-A9 - Page 182

6–52 350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
S3 PROTECTION CHAPTER 6: SETPOINTS
Figure 6-22: Ground/Sensitive Ground instantaneous overcurrent protection logic
diagram
SETPOINT
Ground/Sens. Ground current (Ig)
RUN
SETPOINT
BLOCK 1: Off = 0
GND IOC PICKUP:
Ig > 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
From Ground CT or,
From Sens. Ground CT
Block Inputs
AND
SETPOINT:
Do Not Operate, Operate
OUTPUT RELAY X
AND
Trip (To Breaker Failure)
SETPOINT
GND IOC FUNCTION: Disabled = 0
Latched Alarm Alarm
Trip
GND IOC PKP DELAY:
SETPOINT
t
PKP
0
Event Recorder
Transient Recorder
Autoreclose
(per shot settings)
LED: ALARM
RESET
Command
AND
S R
LATCH
LED: PICKUP
Ground IOC PKP
Message:
Ground IOC OP
898005A2.cdr
GND
IOC DIRECTION
:
Forward
Disabled
Reverse
AND AND
GND DIR Reverse
From GROUND DIRECTIONAL
GND DIR Forward
OR
BLK GND DIR OC UND
AND
SETPOINT