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350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
S4 CONTROLS
CHAPTER 6: SETPOINTS
CT FAIL TIME DELAY
Range: 0.00 to 60.00 s in steps of 0.01 s
Default: 0.10 s
This setting defines the time for CT failure to operate.
Figure 6-60: CT failure detection logic diagram
SETPOINTS
OR
OR
AND
SETPOINT
FUNCTION
:
Disabled
=
0
Latched
Alarm
Alarm
LED
:ALARM
RESET
Command
AND
S
R
LA
TCH
3I
0
CURRENT
PKP
Computed Neutral current
(IN
)
Event Recorder
Transient Recorder
SETPOINTS
Do Not Operate, Operate
OUTPUT
RELA
Y X
AND
CT
Fail OP
SETPOINT
BLOCK
1:
Of
f=
0
BLOCK
2:
Of
f=
0
BLOCK
3:
Of
f=
0
OR
AND
3I
0
>
PKP
RUN
3V
0
VOL
TAGE INHIBIT
3V0
>
INHIBIT
LEVEL
RUN
Neutral voltage
(V
N
)
GND CURRENT
INHIBIT
Ig
>
INHIBIT
LEVEL
RUN
Ground current
(Ig
)
SETPOINTS
OR
t
TIME DELA
Y
SETPOINT
pkp
20
ms
CT
Fail PKP
CT
Fail DPO
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