Sensitive Ground Current - GE F650 Instruction Manual

5 SETTINGS
Table 5–57: QUANTITIES
POLARIZING MODE
VOLTAGE (Vo)
CURRENT (Ip)
Vo + Ip
Vo * Ip
The F650 Sensitive ground Current menu incorporates the following overcurrent elements:
• Sensitive ground time overcurrent (51SG)
• Sensitive ground instantaneous overcurrent (50SG)
• Isolated ground overcurrent (50IG)
• Sensitive ground directional overcurrent (67SG)
5.4.6.1 SENSITIVE GROUND TIME DELAYED OVERCURRENT ELEMENT (51SG)
Sensitive Ground TOC is a sensitive ground time delayed overcurrent protection element with a setting range 0.005A to
16A. The sensitive ground current input quantity is measured from the sensitive ground input, terminals B11-B12, 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. And it incorporates a reset time selectable between instantaneous or linear.
Table 5–58: 51SG ELEMENT SETTINGS
SETPOINT > PROTECTION ELEMENTS > SENSITIVE GROUND CURRENT > SENSITIVE GROUND TOC
SENSITIVE GROUND TOC 1> SENSITIVE GROUND TOC 2 > SENSITIVE GROUND TOC 3
SETTING DESCRIPTION
Function permission
Input type
Pickup level
Curve shape
Time Dial
Reset type
Snapshot Event generation
The snapshot event setting enables or disables the snapshot event generation for this element.
GEK-106310AB
DIRECTION
FORWARD
REVERSE
FORWARD
REVERSE
FORWARD
REVERSE
FORWARD
REVERSE
NAME DEFAULT VALUE
Function DISABLED
Input PHASOR(DFT)
Pickup Level 0.050
Curve IEEE Ext Inv
TD Multiplier 1.00
Reset INSTANTANEOUS
Snapshot Events ENABLED
F650 Digital Bay Controller
5.4 PROTECTION ELEMENTS
COMPARED PHASORS
-Vo Io x 1 MTA
-Vo -Io x 1 MTA
Isg Io
Isg -Io
- Vo Io
or
Isg Io
- Vo -Io
or
Isg -Io
- Vo Io
and
Isg Io
- Vo -Io
and
Isg -Io

5.4.6 SENSITIVE GROUND CURRENT

STEP RANGE
N/A [DISABLED – ENABLED]
N/A [PHASOR – RMS]
0.001 A [0.005 : 16.000]
N/A [See list of curves]
0.01 s [0.00 : 900.00]
N/A [INSTANTANEOUS – LINEAR]
N/A [DISABLED – ENABLED]
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