Ground Instantaneous Overcurrent Protection - GE 845 Instruction Manual

CHAPTER 4: SETPOINTS
Ground Instantaneous
Overcurrent
Protection
845 TRANSFORMER PROTECTION SYSTEM – INSTRUCTION MANUAL
The 845 relay is equipped with the Ground Instantaneous Overcurrent protection element.
The settings of this function are applied to the measured Ground current for producing
Pickup and Trip flags. The Ground IOC Pickup flag is asserted when the Ground current is
above the PKP value. The Ground IOC Operate flag is asserted if the element stays picked-
up for the time defined by the Ground IOC PKP Delay setting. If the Pickup time delay is set
to 0.000 seconds, the Pickup and Operate flags will be asserted at the same time. The
element drops from Pickup without operation if the Ground current drops below 97 to 98%
of the Pickup value.
Path:
Setpoints > Protection > Group 1(6) > Current > Ground IOC 1
FUNCTION
Range: Disabled, Trip, Alarm, Latched Alarm, Configurable
Default: Disabled
PICKUP
Range: 0.050 to 30.000 x CT in steps of 0.001 x CT
Default: 1.00 x CT
DIRECTION
Range: Disabled, Forward, Reverse
Default: Disabled
PICKUP DELAY
Range: 0.000 to 6000.000 s in steps of 0.001 s
Default: 0.000 s
DROPOUT DELAY
Range: 0.000 to 6000.000 s in steps of 0.001 s
Default: 0.000 s
BLOCK
Range: Off, Any operand from the list of FlexLogic operands
Default: Off
RELAYS
Range: Do Not Operate, Operate
Default: Do Not Operate
EVENTS
Range: Enabled, Disabled
Default: Enabled
TARGETS
Range: Self-reset, Latched, Disabled
Default: Self-reset
PROTECTION
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