CHAPTER 6: SETPOINTS
S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
6–63
Figure 6-26: Negative Sequence Timed Overcurrent logic diagram
Calculated Negative
Sequence Current
SETPOINT
NEG SEQ
TOC FUNCTN:
Disabled
=
0
Latched
Alarm
AND
LED:
TRIP
Alarm
OR
OR
AND
SETPOINTS
Do Not Operate, Operate
OUTPUT
RELA
Y X
Trip
AND
To
Breaker Failure
Trip
SETPOINTS
BLOCK
1:
Of
f=
0
BLOCK
2:
Of
f=
0
BLOCK
3:
Of
f=
0
OR
LED:
PICKUP
Event Recorder
Event Recorder
I_
2
LED:
ALARM
RESET
Command
AND
S
R
LA
TCH
SETPOINTS
RUN
NEG SEQ
TOC PICKUP
NEG SEQ
TOC CUR
VE
NEG SEQ
TO
C
TDM
I_
2
>
PICKUP
Adjust PKP
NEG SEQ
TOC RESET
I_2
x t
=
Transient Recorder
897807A1.cdr
Operate Output Relay 1
Transient Recorder