GE Multilin 345 - Page 186

6–70 345 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
S3 PROTECTION CHAPTER 6: SETPOINTS
Figure 6-29: Ground/Sensitive Ground Instantaneous Overcurrent Protection logic
diagram
SETPOINT
RUN
SETPOINT
BLOCK 1 Off = 0
GND IOC PICKUP
Ig > PICKUP
BLOCK 2 Off = 0 BLOCK 3 Off = 0
OR
AND
OR
OR
AND AND
SETPOINT
GND IOC FUNCTION Disabled = 0
Latched Alarm Alarm
Trip
GND IOC PKP DELAY
SETPOINT
t
PKP
0
LED: ALARM
RESET
Command
AND
S R
LATCH
LED: TRIP
To Breaker Failure
Trip
SETPOINTS
( configurable only if “TRIP”
function selected )
Operate trip output relays upon selection
RLY 2 TRIP W2 BKR
SETPOINTS
Do Not Operate, Operate
OUTPUT RELAY X
Message and Event Recorder
GND TOC OP
Ground/Sens. Ground current (Ig)
CT(W1), CT(W2) ground current selected under GND TOC CT INPUT
GND IOC CT INPUT
LED: PICKUP
Message and Event Recorder
GND TOC PKP
RLY 1 TRIP W1 BKR
897811A1.cdr