GE MiCOM P40 Agile Technical Manual page 553

Symbols and Glossary
MiCOM P40 Agile P442, P444
Symbols Explanation
V Zero sequence voltage:
0
Equals one third of the measured neutral/residual voltage.
V Positive sequence voltage.
1
V Negative sequence voltage.
2
V2pol Negative sequence polarizing voltage.
VA Phase A voltage: Might be phase L1, red phase. or other, in customer terminology.
VB Phase B voltage: Might be phase L2, yellow phase. or other, in customer terminology.
VC Phase C voltage: Might be phase L3, blue phase. or other, in customer terminology.
VCO Voltage controlled overcurrent element.
Vk IEC knee point voltage of a current transformer.
Vn The rated nominal voltage of the relay:
To match the line VT input.
VN Neutral voltage displacement or residual voltage.
VN>1 First stage of residual (neutral) overvoltage protection.
VN>2 Second stage of residual (neutral) overvoltage protection.
Vres. Neutral voltage displacement or residual voltage.
VT Voltage transformer.
VTS Voltage transformer supervision (to detect VT input failure).
Vx An auxiliary supply voltage:
Typically the substation battery voltage used to power the relay.
WI Weak Infeed
YN> Neutral overadmittance protection element:
Non-directional neutral admittance protection calculated from neutral current and residual
voltage.
Z1...ZQ Zone 1, 2, 3, 4, P or Q.
Z1X Zone 1 Extended
Z Zero sequence impedance.
0
Z Positive sequence impedance.
1
Z Negative sequence impedance.
2
ZSP Zero Sequence Power (Earth Fault Protection)
P44x/EN SG/ Hb6
(SG) 13-9