CHAPTER 6: SETPOINTS
S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–79
Figure 6-34: Neutral Overvoltage logic diagram
Calculated Neutral
V
oltage V0
SETPOINTS
SETPOINT
NTRL
OV FUNCTION:
Disabled = 0
Latched
Alarm
NTRL
OV PICKUP:
AND
Operate Output Relay 1 (TRIP)
Event Recorder
LED:
TRIP
Alarm
OR
OR
AND
SETPOINTS:
Do Not Operate, Operate
OUTPUT
RELA
Y X
Trip
AND
Trip (T
o Breaker Failure)
SETPOINTS
BLOCK 1:
Of
f = 0
BLOCK 2:
Of
f = 0
BLOCK 3:
Of
f = 0
OR
RUN
Vn = 3V0
LED: PICKUP
Neutrl OV
Trip (Alarm) - PKP
, OP
Message
3V0 > PICKUP
NTRL
OV DELA
Y:
SETPOINT
t
PKP
LED:
ALARM
RESET
Command
AND
S
R
LA
TCH
898015A2.cdr