GE Multilin 850 Instruction Manual page 277

CHAPTER 4: SETPOINTS
REV Operating
Region
-ECA line
-Ig line
VCG
850 FEEDER PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 4-54: Ground Directional Voltage-polarized Characteristics
REV LA
line
LA
LA
REV LA
line
Path:
Setpoints > Protection > Group 1(6) > Current > Ground Directional OC 1(X)
FUNCTION
Range: Disabled, Enabled
Default: Disabled
POLARIZING MODE
Range: Voltage, Current, Dual
Default: Voltage
This setting selects the polarizing mode for the directional unit.
• If Voltage polarizing mode is selected, the element uses the zero-sequence voltage
angle for polarization. The user can select either the zero-sequence voltage V_0,
calculated from the phase voltages, or the zero-sequence voltage supplied externally
as the auxiliary voltage V_X.
The calculated V_0 can be used as polarizing voltage only if the voltage transformers
are connected in Wye. The auxiliary voltage can be used as the polarizing voltage if
the auxiliary voltage is connected to a zero-sequence voltage source (such as the
open delta connected secondary of VTs).
-3V_0 line
FWD LA
line
VAG
(reference)
LA
ECA
FWD LA
line
3V_0 line
PROTECTION
FWD Operating
Region
Ig line
ECA line
LA
VBG
827805X1.CDR
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