Neutral Time Overcurrent (Ansi 51N, Iec Ptoc); Neutral Time Overcurrent 1 Scheme Logic - GE T60 Instruction Manual

5 SETTINGS
b) NEUTRAL TIME OVERCURRENT (ANSI 51N, IEC PTOC)
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PATH: SETTINGS GROUPED ELEMENTS
 NEUTRAL TOC1
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MESSAGE
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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" (see the Inverse TOC Curve Characteristics
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 "Instantaneous" and the
element is blocked, the time accumulator will be cleared immediately.
SETTING
NEUTRAL TOC1
FUNCTION:
Enabled = 1
SETTING
NEUTRAL TOC1
SOURCE:
IN
SETTING
NEUTRAL TOC1
BLOCK:
Off = 0
Figure 5–111: NEUTRAL TIME OVERCURRENT 1 SCHEME LOGIC
GE Multilin
 
SETTING GROUP 1(6) NEUTRAL CURRENT
NEUTRAL TOC1
FUNCTION: Disabled
NEUTRAL TOC1 SIGNAL
SOURCE: SRC 1
NEUTRAL TOC1
INPUT: Phasor
NEUTRAL TOC1
PICKUP: 1.000 pu
NEUTRAL TOC1
CURVE: IEEE Mod Inv
NEUTRAL TOC1
TD MULTIPLIER: 1.00
NEUTRAL TOC1
RESET: Instantaneous
NEUTRAL TOC1 BLOCK:
Off
NEUTRAL TOC1
TARGET: Self-reset
NEUTRAL TOC1
EVENTS: Disabled
SETTINGS
NEUTRAL TOC1
INPUT:
NEUTRAL TOC1
PICKUP:
NEUTRAL TOC1
CURVE:
NEUTRAL TOC1
TD MULTIPLIER:
NEUTRAL TOC 1
RESET:
RUN
AND
IN PICKUP
t
I
T60 Transformer Protection System
5.6 GROUPED ELEMENTS

NEUTRAL TOC1(6)
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4, SRC 5, SRC 6
Range: Phasor, RMS
Range: 0.000 to 30.000 pu in steps of 0.001
Range: See OVERCURRENT CURVE TYPES table
Range: 0.00 to 600.00 in steps of 0.01
Range: Instantaneous, Timed
Range: FlexLogic operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
FLEXLOGIC OPERANDS
NEUTRAL TOC1 PKP
NEUTRAL TOC1 DPO
NEUTRAL TOC1 OP
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