GE C70 Instruction Manual page 297

CHAPTER 5: SETTINGS
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
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.
— This setting enables and disables the neutral time overcurrent protection element.
NEUTRAL TOC1 FUNCTION
NEUTRAL TOC1 SIGNAL SOURCE
— This setting selects how neutral current input quantities are interpreted by the C70. Inputs can be
NEUTRAL TOC1 INPUT
selected as fundamental phasor magnitudes or total waveform RMS magnitudes as required by the application.
— This setting specifies the neutral time overcurrent pickup level in per-unit values.
NEUTRAL TOC1 PICKUP
— This setting selects the inverse time overcurrent curve style.
NEUTRAL TOC1 CURVE
NEUTRAL TOC1 TD MULTIPLIER
Programming this value to zero results in an instantaneous response to all current levels above pickup.
— The "Instantaneous" reset method is intended for applications with other relays, such as most static
NEUTRAL TOC1 RESET
relays, which set the energy capacity directly to zero when the current falls below the reset threshold. The "Timed" reset
method can be used where the relay must coordinate with electromechanical relays.
— Assertion of the operand assigned to this setting blocks operation of the neutral time overcurrent
NEUTRAL TOC1 BLOCK
element.
— This setting enables and disables the logging of neutral time overcurrent events in the sequence
NEUTRAL TOC1 EVENTS
of events recorder.
SETTING
NEUTRAL TOC1
FUNCTION:
Enabled = 1
SETTING
NEUTRAL TOC1
SOURCE:
IN
SETTING
NEUTRAL TOC1
BLOCK:
Off = 0
5.7.4.3 Neutral instantaneous overcurrent (ANSI 50N, IEC PIOC)
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  NEUTRAL CURRENT  NEUTRAL IOC1(12)
 NEUTRAL IOC1

C70 CAPACITOR BANK PROTECTION AND CONTROL SYSTEM – INSTRUCTION MANUAL
— This setting selects the signal source for the neutral time overcurrent protection element.
— This setting specifies a multiple of the base curve shape specified by the
Figure 5-82: Neutral time overcurrent 1 logic
SETTINGS
NEUTRAL TOC1
INPUT:
NEUTRAL TOC1
PICKUP:
NEUTRAL TOC1
CURVE:
NEUTRAL TOC1
TD MULTIPLIER:
NEUTRAL TOC 1
RESET:
AND RUN
NEUTRAL IOC1

FUNCTION: Disabled
NEUTRAL IOC1 SIGNAL

SOURCE: SRC 1
NEUTRAL IOC1

PICKUP: 1.000 pu
NEUTRAL IOC1 PICKUP

DELAY: 0.00 s
NEUTRAL IOC1 RESET

DELAY: 0.00 s
NEUTRAL IOC1 BLOCK:

Off
FLEXLOGIC OPERANDS
NEUTRAL TOC1 PKP
NEUTRAL TOC1 DPO
IN PICKUP
NEUTRAL TOC1 OP
t
I
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4, SRC 5, SRC 6
Range: 0.000 to 30.000 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
GROUPED ELEMENTS
setting.
CURVE
827034A4.VSD
5-173
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