GE C70 Instruction Manual page 399

CHAPTER 5: SETTINGS
Recloser curves
The C70 uses the FlexCurve feature to facilitate programming of 41 recloser curves. See the FlexCurves settings section
earlier in this chapter for details.
5.7.3.3 Phase time overcurrent (ANSI 51P, IEC PTOC)
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  PHASE CURRENT  PHASE TOC1(6)
 PHASE TOC 1

The phase time overcurrent element can provide a specified time-delay operating characteristic versus the applied current
or be used as a simple definite time element. The phase current input quantities can 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 earlier for details on curve setup, trip times, and reset operation). When the element is blocked, the time
accumulator resets according to the reset characteristic. For example, if the element reset characteristic is set to
"Instantaneous" and the element is blocked, the time accumulator clears immediately.
The setting can be reduced dynamically by a voltage restraint feature (when enabled). This is
PHASE TOC1 PICKUP
accomplished via the multipliers (Mvr) corresponding to the phase-phase voltages of the voltage restraint characteristic
curve (see the figure); the pickup level is calculated as Mvr times the
feature is disabled, the pickup level always remains at the setting value.
The Phase TOC element can be used as a basic thermal overload protection element, using I
2
characteristic with I t is based on the current squared, integrated over time during fault. The
asserted indicating that protected apparatus is cooled down and can be safely put back into service.
C70 CAPACITOR BANK PROTECTION AND CONTROL SYSTEM – INSTRUCTION MANUAL
PHASE TOC1

FUNCTION: Disabled
PHASE TOC1 SIGNAL

SOURCE: SRC 1
PHASE TOC1

INPUT: Phasor
PHASE TOC1

PICKUP: 1.000 pu
PHASE TOC1

CURVE: IEEE Mod Inv
PHASE TOC1

TD MULTIPLIER: 1.00
PHASE TOC1

RESET: Instantaneous
PHASE TOC1 VOLTAGE

RESTRAINT: Disabled
PHASE TOC1 BLOCK A:

Off
PHASE TOC1 BLOCK B:

Off
PHASE TOC1 BLOCK C:

Off
PHASE TOC1

TARGET: Self-reset
PHASE TOC1

EVENTS: Disabled
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4, SRC 5, SRC 6
Range: Phasor, RMS
Range: 0.020 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: Disabled, Enabled
Range: FlexLogic operand
Range: FlexLogic operand
Range: FlexLogic operand
Range: Self-reset, Latched, Disabled
Range: Disabled, Enabled
setting. If the voltage restraint
PHASE TOC1 PICKUP
2
t curves. The thermal time
PHASE TOC 1 I2t RST
GROUPED ELEMENTS
5
operand is
5-195