Neutral Current - GE UR Series Instruction Manual

5.5 GROUPED ELEMENTS
a) NEUTRAL TOC1 / TOC2 (NEUTRAL TIME OVERCURRENT: ANSI 51N)
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PATH: SETTINGS GROUPED ELEMENTS
„
NEUTRAL TOC1
„
5
The neutral time overcurrent element can provide a desired time-delay operating characteristic versus the applied current
or be used as a simple Definite Time element. The neutral current input value is a quantity calculated as 3Io from the phase
currents and may be programmed as fundamental phasor magnitude or total waveform RMS magnitude as required by the
application.
Two methods of resetting operation are available: "Timed" and "Instantaneous" (refer to the INVERSE TOC CURVE CHAR-
ACTERISTICS section for details on curve setup, trip times and reset operation). When the element is blocked, the time
accumulator will reset according to the reset characteristic. For example, if the element reset characteristic is set to "Instan-
taneous" and the element is blocked, the time accumulator will be cleared immediately.
SETTING
NEUTRAL TOC1
FUNCTION:
Disabled = 0
Enabled = 1
SETTING
NEUTRAL TOC1
SOURCE:
IN
SETTING
NEUTRAL TOC1
BLOCK:
Off = 0
Once picked up, the NEUTRAL TOCx PKP output operand remains picked up until the thermal memory of
the element resets completely. The PKP operand will not reset immediately after the operating current
NOTE
drops below the pickup threshold unless
5-92
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SETTING GROUP 1(8)
NEUTRAL TOC1
FUNCTION: Disabled
NEUTRAL TOC1 SIGNAL
MESSAGE
SOURCE: SRC 1
NEUTRAL TOC1
MESSAGE
INPUT: Phasor
NEUTRAL TOC1
MESSAGE
PICKUP:
NEUTRAL TOC1
MESSAGE
CURVE: IEEE Mod Inv
NEUTRAL TOC1
MESSAGE
TD MULTIPLIER:
NEUTRAL TOC1
MESSAGE
RESET: Instantaneous
NEUTRAL TOC1 BLOCK:
MESSAGE
Off
NEUTRAL TOC1
MESSAGE
TARGET: Self-reset
NEUTRAL TOC1
MESSAGE
EVENTS: Disabled
AND
Figure 5–42: NEUTRAL TOC1 SCHEME LOGIC
L90 Line Differential Relay
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NEUTRAL CURRENT

Range: Disabled, Enabled
Range: SRC 1, SRC 2,..., SRC 6
Range: Phasor, RMS
Range: 0.000 to 30.000 pu in steps of 0.001
1.000 pu
Range: See OVERCURRENT CURE TYPES table
Range: 0.00 to 600.00 in steps of 0.01
1.00
Range: Instantaneous, Timed
Range: FlexLogic™ operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
SETTINGS
NEUTRAL TOC1
INPUT:
NEUTRAL TOC1
PICKUP:
NEUTRAL TOC1
CURVE:
NEUTRAL TOC1
TD MULTIPLIER:
NEUTRAL TOC 1
RESET:
RUN
IN ³ PICKUP
t
I
is set to "Instantaneous".
NEUTRL TOCx RESET
5 SETTINGS
5.5.13 NEUTRAL CURRENT
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NEUTRAL TOC1
FLEXLOGIC OPERANDS
NEUTRAL TOC1 PKP
NEUTRAL TOC1 DPO
NEUTRAL TOC1 OP
827034A3.VSD
GE Power Management