Ground Current - GE Multilin W650 Instruction Manual

5.4 PROTECTION ELEMENTS
The Ground Current menu incorporates the following overcurrent elements:
Ground time overcurrent (51G)
Ground instantaneous overcurrent (50G)
Ground directional element (67G)
5.4.5.1 GROUND TIME DELAYED OVERCURRENT ELEMENT (51G)
Ground TOC is a ground time delayed overcurrent protection element. The ground current is measured from the ground
input, terminals B9-B10, and it may be programmed as Fundamental phasor magnitude or RMS magnitude as required by
the application. The element trip can be time delayed using a selectable curve. It incorporates a reset time that is selectable
between instantaneous or linear.
Table 5–51: 51G ELEMENT SETTINGS
SETPOINT > PROTECTION ELEMENTS > GROUND CURRENT > GROUND TOC
GROUND TOC 1> GROUND TOC 2 > GROUND TOC 3
SETTING DESCRIPTION
Function permission
Input type
Pickup level
Curve shape
5
Time Dial
Reset type
Snapshot Event generation
The snapshot event setting enables or disables the snapshot event generation for this element.
5.4.5.2 GROUND INSTANTANEOUS OVERCURRENT ELEMENT (50G)
Ground IOC is a ground instantaneous overcurrent protection element, with a setting range from 0.05 A to 160 A, which can
also be time delayed. The delay is selectable between 0.00 and 900 seconds. The ground current input quantity is
measured from the ground input, and it may be programmed as Fundamental phasor magnitude or RMS magnitude as
required by the application. The element incorporates a reset time selectable between 0 and 900 seconds, and a block
input that resets the pickup and trip signals to 0. The element outputs are the general pickup and trip signals of the element.
Table 5–52: 50G ELEMENT SETTINGS
SETPOINT > PROTECTION ELEMENTS > GROUND CURRENT > GROUND IOC
GROUND IOC 1> GROUND IOC 2 > GROUND IOC 3
SETTING DESCRIPTION
Function permission
Input type
Pickup level
Trip time
Reset time
Snapshot event generation
The snapshot event setting enables or disables the snapshot event generation for this element.
5-56
NAME DEFAULT VALUE
Function DISABLED
Input PHASOR(DFT)
Pickup Level 1.00
Curve IEEE Ext Inv
TD Multiplier 1.00
Reset INSTANTANEOUS N/A
Snapshot Events ENABLED
NAME DEFAULT VALUE STEP
Function DISABLED
Input PHASOR(DFT)
Pickup Level 30.00
Trip Delay 0.00
Reset Delay 0.00
Snapshot Events ENABLED
W650 Wind Generator Protection System

5.4.5 GROUND CURRENT

STEP RANGE
N/A [DISABLED – ENABLED]
N/A [PHASOR – RMS]
0.01 A [0.05 : 160.00]
N/A [See list of curves]
0.01 s [0.00 : 900.00]
[INSTANTANEOUS – LINEAR]
N/A [DISABLED – ENABLED]
RANGE
N/A [DISABLED – ENABLED]
N/A [PHASOR – RMS]
0.01 A [0.05 : 160.00]
0.01 s [0.00 : 900.00]
0.01 s [0.00 : 900.00]
N/A [DISABLED – ENABLED]
5 SETTINGS
GEK-113032A