GE G60

5-184 G60 Generator Protection System GE Multilin
5.6 GROUPED ELEMENTS 5 SETTINGS
5
c) PHASE TIME OVERCURRENT (ANSI 51P, IEC PTOC)
PATH: SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  PHASE CURRENT  PHASE TOC1
The phase 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 phase current input quantities 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 Time overcurrent
curves characteristic sub-section earlier 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 characteris-
tic is set to “Instantaneous” and the element is blocked, the time accumulator will be cleared immediately.
The
PHASE TOC1 PICKUP setting can be dynamically reduced by a voltage restraint feature (when enabled). This is accom-
plished via the multipliers (Mvr) corresponding to the phase-phase voltages of the voltage restraint characteristic curve
(see the figure below); the pickup level is calculated as ‘Mvr’ times the
PHASE TOC1 PICKUP setting. If the voltage restraint
feature is disabled, the pickup level always remains at the setting value.
 PHASE TOC1

PHASE TOC1
FUNCTION: Disabled
Range: Disabled, Enabled
MESSAGE
PHASE TOC1 SIGNAL
SOURCE: SRC 1
Range: SRC 1, SRC 2, SRC 3, SRC 4
MESSAGE
PHASE TOC1
INPUT: Phasor
Range: Phasor, RMS
MESSAGE
PHASE TOC1
PICKUP: 1.000 pu
Range: 0.000 to 30.000 pu in steps of 0.001
MESSAGE
PHASE TOC1
CURVE: IEEE Mod Inv
Range: See Overcurrent Curve Types table
MESSAGE
PHASE TOC1
TD MULTIPLIER: 1.00
Range: 0.00 to 600.00 in steps of 0.01
MESSAGE
PHASE TOC1
RESET: Instantaneous
Range: Instantaneous, Timed
MESSAGE
PHASE TOC1 VOLTAGE
RESTRAINT: Disabled
Range: Disabled, Enabled
MESSAGE
PHASE TOC1 BLOCK A:
Off
Range: FlexLogic operand
MESSAGE
PHASE TOC1 BLOCK B:
Off
Range: FlexLogic operand
MESSAGE
PHASE TOC1 BLOCK C:
Off
Range: FlexLogic operand
MESSAGE
PHASE TOC1
TARGET: Self-reset
Range: Self-reset, Latched, Disabled
MESSAGE
PHASE TOC1
EVENTS: Disabled
Range: Disabled, Enabled