GE F60 Instruction Manual page 396

GROUPED ELEMENTS
The ground instantaneous overcurrent element can be used as an instantaneous element with no intentional delay or as a
definite time element. The ground current input is the quantity measured by the ground input CT and is the fundamental
phasor magnitude.
These elements measure the current that is connected to the ground channel of a CT/VT module. The conversion
range of a standard channel is from 0.02 to 46 times the CT rating.
This channel can be equipped with a standard or sensitive input. The conversion range of a sensitive channel is
from 0.002 to 4.6 times the CT rating.
5
5.7.7.4 Restricted ground fault (ANSI 87RGF, IEC PNDF)
SETTINGS  GROUPED ELEMENTS  SETTING GROUP 1(6)  GROUND CURRENT  RESTRICTED GROUND FAULT
1(4)
 RESTRICTED GROUND
 FAULT 1
Restricted ground fault (RGF) protection provides sensitive ground fault detection for low-magnitude fault currents,
primarily faults close to the neutral point of a wye-connected winding. An internal ground fault on an impedance grounded
wye winding produces a fault current dependent on the ground impedance value and the fault position on the winding
with respect to the neutral point. The resultant primary current is negligible for faults on the lower 30% of the winding
5-222
GROUND IOC1

EVENTS: Disabled
Figure 5-113: Ground IOC1 logic
RESTD GND FT1

FUNCTION: Disabled
RESTD GND FT1

SOURCE: SRC 1
RESTD GND FT1

PICKUP: 0.080 pu
RESTD GND FT1

SLOPE: 40%
RESTD GND FT1 PICKUP

DELAY: 0.10 s
RESTD GND FT1 RESET

DELAY: 0.00 s
RESTD GND FT1 BLOCK:

Off
RESTD GND FT1

TARGET: Self-reset
Range: Disabled, Enabled
Range: Disabled, Enabled
Range: SRC 1, SRC 2, SRC 3, SRC 4
Range: 0.005 to 30.000 pu in steps of 0.001
Range: 0 to 100% in steps of 1
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
Range: Self-reset, Latched, Disabled
F60 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
CHAPTER 5: SETTINGS