GE L90 Instruction Manual page 235

5 SETTINGS
d) NEUTRAL OVERVOLTAGE (ANSI 59N)
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PATH: SETTINGS GROUPED ELEMENTS
# NEUTRAL OV1
#
MESSAGE
MESSAGE
MESSAGE
MESSAGE
MESSAGE
MESSAGE
MESSAGE
The Neutral Overvoltage element can be used to detect asymmetrical system voltage condition due to a ground fault or to
the loss of one or two phases of the source. The element responds to the system neutral voltage (3V_0), calculated from
the phase voltages. The nominal secondary voltage of the phase voltage channels entered under
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SETUP AC INPUTS VOLTAGE BANK
VT errors and normal voltage unbalance must be considered when setting this element. This function requires the VTs to
be Wye connected.
SETTING
NEUTRAL OV1
FUNCTION:
Disabled=0
Enabled=1
SETTING
NEUTRAL OV1 BLOCK:
Off=0
SETTING
NEUTRAL OV1 SIGNAL
SOURCE:
ZERO SEQ VOLT (V_0)
GE Multilin
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SETTING GROUP 1(6)
NEUTRAL OV1
FUNCTION: Disabled
NEUTRAL OV1 SIGNAL
SOURCE: SRC 1
NEUTRAL OV1 PICKUP:
0.300 pu
NEUTRAL OV1 PICKUP:
DELAY: 1.00 s
NEUTRAL OV1 RESET:
DELAY: 1.00 s
NEUTRAL OV1 BLOCK:
Off
NEUTRAL OV1 TARGET:
Self-reset
NEUTRAL OV1 EVENTS:
Disabled
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PHASE VT SECONDARY
SETTING
NEUTRAL OV1 PICKUP:
AND RUN
<
3V_0 Pickup
Figure 5–88: NEUTRAL OVERVOLTAGE1 SCHEME LOGIC
L90 Line Differential Relay
5.5 GROUPED ELEMENTS
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VOLTAGE ELEMENTS NEUTRAL OV1
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4
Range: 0.000 to 1.250 pu in steps of 0.001
Range: 0.00 to 600.00 s in steps of 0.01
Range: 0.00 to 600.00 s in steps of 0.01
Range: FlexLogic™ operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
is the p.u. base used when setting the pickup level.
SETTING
NEUTRAL OV1 PICKUP
DELAY :
NEUTRAL OV1 RESET
DELAY :
t
PKP
t
RST
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SETTINGS SYSTEM
FLEXLOGIC OPERANDS
NEUTRAL OV1 OP
NEUTRAL OV1 DPO
NEUTRAL OV1 PKP
827848A1.CDR
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