GE 889 Instruction Manual page 329

CHAPTER 4: SETPOINTS
REV Operating
Region
-ECA line
-Isg line
VCG
NOTE:
NOTE
889 GENERATOR PROTECTION SYSTEM – INSTRUCTION MANUAL
Figure 4-70: Sensitive Ground Directional Voltage-polarized Characteristics
REV LA
line
LA
LA
REV LA
line
Path:
Setpoints > Protection > Group 1(6) > Current > Sens Ground Directional OC 1(X)
FUNCTION
Range: Disabled, Enabled
Default: Disabled
POLARIZING MODE
Range: Voltage, Current, Dual
Default: Voltage
It is not recommended to use this function in the case of 50:0.025A CT input. If this is
applied consider Isg phasor metering errors in magnitude and angle in the settings.
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.
-3V_0 line
FWD LA
line
VAG
(reference)
LA
ECA
FWD LA
line
3V_0 line
PROTECTION
FWD Operating
Region
Isg line
ECA line
LA
VBG
827805Y1.CDR
4–199