GE 350-A9 - Page 211

CHAPTER 6: SETPOINTS S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 6–81
Figure 6-35: Negative Sequence Overvoltage logic diagram
Calculated Negative
Sequence Voltage
SETPOINTS
SETPOINT
NEG SEQ OV FUNCTN: Disabled = 0
Latched Alarm
NEG SEQ OV PICKUP:
AND
Operate Output Relay 1 (TRIP)
Event Recorder
LED: TRIP
Alarm
OR
OR
AND
SETPOINTS:
Do Not Operate, Operate
OUTPUT RELAY X
Trip
AND
Trip (To Breaker Failure)
SETPOINTS
BLOCK 1: Off = 0 BLOCK 2: Off = 0 BLOCK 3: Off = 0
OR
RUN
V_2
Phase VT connection
DeltaWye
LED: PICKUP
NegSeq Overvoltage
Message
V_2 or  3*V_2 > PICKUP
NEG SEQ OV DELAY:
SETPOINT
t
PKP
 3 * V_2
LED: ALARM
RESET
Command
AND
S R
LATCH
898016A2.cdr