GE Multilin 350 Series - Page 203

CHAPTER 6: SETPOINTS S3 PROTECTION
350 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL 6–87
Figure 25: Neutral directional logic diagram
Zero Sequence Voltage (-V0)
SETPOINT
NTRL DIR FUNCTION Disabled = 0
Latched Alarm
SETPOINTS
BLOCK 1 Off = 0 BLOCK 2 Off = 0 BLOCK 3 Off = 0
OR
NTRL DIR REVERSE
(To Neutral TOC and Neutral IOC )
Alarm
OR
OR
REVERSE
(Message)
AND
SETPOINT:
Operate
Output Relays
Upon
Selection
OUTPUT RELAY 4 OUTPUT RELAY 5 OUTPUT RELAY 6 OUTPUT RELAY 3
Control
Neutral Current (In) Ground current (Ig)
Voltage Polarization
-3V_0
3I_0
FWD
REV
REV
RUN
SETPOINT
NTRL DIR MTA
Current Polarization
REV
RUN
SETPOINT
NTRL DIR POLARIZING: Current
Dual Voltage
OR OR
SETPOINT
MIN POL VOLTAGE |V0| > MINIMUM
AND
Ig>0.05xCT
AND
In>0.05xCT
AND
OR XOR
AND
NAND
AND
Ntrl Dir Reverse
(Event Recorder, Transient Recorder)
Direction OK
LED: ALARM
RESET
Command
898017A1.cdr
AND
LATCH
S
R
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