GE L90 Instruction Manual page 215

5 SETTINGS
SETTING
NEUTRAL DIR OC1
FUNCTION:
Disabled=0
Enabled=1
SETTING
AND
NEUTRAL DIR OC1 BLK:
Off=0
SETTING
NEUTRAL DIR OC1
SOURCE:
NEUTRAL DIR OC1 POL
VOLT:
NEUTRAL DIR OC1 OP
CURR:
}
Measured VX
Calculated V_0
Zero Seq Crt (I_0)
Ground Crt (IG)
SETTING
G 0.05 pu
NEUTRAL DIR OC1
POLARIZING:
Voltage
OR
Current
Dual
OR
NOTE:
1) CURRENT POLARIZING IS POSSIBLE ONLY IN RELAYS WITH
THE GROUND CURRENT INPUTS CONNECTED TO
AN ADEQUATE CURRENT POLARIZING SOURCE
2) GROUND CURRENT CAN NOT BE USED FOR POLARIZATION
AND OPERATION SIMULTANEOUSLY
3) POSITIVE SEQUENCE RESTRAINT IS NOT APPLIED WHEN
_1 IS BELOW 0.8pu
Figure 5–73: NEUTRAL DIRECTIONAL OVERCURRENT LOGIC
GE Multilin
SETTING
NEUTRAL DIR OC1 FWD
PICKUP:
NEUTRAL DIR OC1 OP
CURR:
NEUTRAL DIR OC1 POS-
SEQ RESTRAINT:
RUN
3( _0 - K _1 ) PICKUP
OR
G PICKUP
SETTINGS
AND
NEUTRAL DIR OC1 FWD
ECA:
NEUTRAL DIR OC1 FWD
LIMIT ANGLE:
NEUTRAL DIR OC1 REV
LIMIT ANGLE:
NEUTRAL DIR OC1
OFFSET:
RUN
FWD
FWD
-3V_0
}
REV
3I_0
REV
Voltage Polarization
AND RUN
FWD
Current Polarization
REV
SETTING
NEUTRAL DIR OC1 REV
PICKUP:
NEUTRAL DIR OC1 OP
CURR:
NEUTRAL DIR OC1 POS-
SEQ RESTRAINT:
RUN
3( _0 - K _1 ) PICKUP
OR
G PICKUP
L90 Line Differential Relay
5.5 GROUPED ELEMENTS
AND
OR
1.25 cy
AND
1.5 cy
OR
AND
FLEXLOGIC OPERAND
AND NEUTRAL DIR OC1 FWD
5
FLEXLOGIC OPERAND
NEUTRAL DIR OC1 REV
827077AB.CDR
5-125