GE F650 Instruction Manual page 228

5 SETTINGS
5.4.9.3 WATTMETRIC GROUND FAULT (32N)
a) WATTMETRIC ZERO-SEQUENCE DIRECTIONAL HIGH AND LOW LEVEL (32NH, 32NL). ELEMENT DESCRIPTION
This document specifies wattmetric zero-sequence directional function, which can be used on solidly grounded, low-
resistance grounded, isolated or resonant (Petersen coil) grounded systems. The function determines presence and
direction of ground faults by measuring value and direction of zero-sequence power.
The element responds to power derived from zero-sequence voltage and current in a direction specified by the element
characteristic angle. The angle can be set within all four quadrants, the power can be selected to be either active or
reactive. Therefore, the element may be used to sense either forward or reverse ground faults in either inductive, capacitive
or resistive networks. Inverse time characteristic allows time coordination of the elements across the network.
Typical applications include ground fault protection in solidly grounded transmission networks, grounded/ungrounded/
resistor-grounded/resonant-grounded distribution networks, or for directionalizing other non-directional ground elements.
b) ELEMENT SETTINGS
SETPOINT > PROTECTION ELEMENTS > POWER >
WATT GND FLT HIGH 1> WATT GND FLT HIGH 2 > WATT GND FLT HIGH 3
WATT GND FLT LOW 1> WATT GND FLT LOW 2 > WATT GND FLT LOW 3
SETTING DESCRIPTION
Function permission
Supervision minimun voltage
Source of operating current.
Pickup Level for Overcurrent
Pickup Delay for Overcurrent
Pickup Level for operating Power
Max torque angle
Pickup Delay for Operating Power
Curve shape
Multiplier
Snapshot event generation
wattmetric ground fault settings are:
Function:
Voltage Pickup Level:
Current selection:
OC Pickup Level:
OC Pickup Delay:
Power Pickup: This setting specifies the operating point of the element.
GEK-106310AB
NAME DEFAULT VALUE
Function DISABLED
Voltage Pickup Level 2.00
Current selection IN
OC Pickup Level 0.005
OC Pickup Delay 0.20
Power Pickup 0.01
MTA 0
Power Pickup Delay 0.20
Curve DEFINITE TIME
Multiplier 1.00
Snapshot Event DISABLED
Enables or disables the directional element.
The element uses neutral, i.e. 3 times zero-sequence, voltage. This setting specifies the
minimum neutral voltage supervising the directional power measurement. This threshold
should be higher than possible unbalance during normal operation of the system.
The element responds to the neutral (3 times zero-sequence) current, either calculated
internally (IN) from the phase currents, or supplied externally (IG) via the ground CT input.
This setting allows selecting the source of the operating current.
This setting specifies the current supervision level for the measurement of the zero-sequence
power.
This setting specifies delay for the overcurrent portion of this element. The delay applies to
the 32N1(2 3) HIGH(LOW) OC PKP operand driven from the overcurrent condition.
F650 Digital Bay Controller
5.4 PROTECTION ELEMENTS
STEP RANGE
N/A [DISABLED-ENABLED]
0.01 V [2.00 : 70.00]
N/A [IN-IG]
0.001A [0.005 : 0.400]
0.01 s [0.00 : 600.00]
0.01 W [0.01 : 4.50]
1 Deg [0 : 360]
0.01 s [0.00 : 600.00]
N/A [DEFINITE TIME - INVERSE TIME -
USER CURVE A - USER CURVE B -
USER CURVE C - USER CURVE D]
0.01 s [0.02 : 2.00]
N/A [DISABLED-ENABLED]
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