ABB RELION 650 Series Applications Manual page 285

1MRK 504 158-UEN A
UV
WEI
VT
3I
O
3U
O
Application manual
sometimes known by the military name, "Zulu time." "Zulu" in the
phonetic alphabet stands for "Z", which stands for longitude zero.
Undervoltage
Weak end infeed logic
Voltage transformer
Three times zero-sequence current.Often referred to as the residual or
the earth-fault current
Three times the zero sequence voltage. Often referred to as the
residual voltage or the neutral point voltage
Section 19
Glossary
279