ABB RELION 650 Series Commissioning Manual page 123

1MRK 504 160-UEN A
UV
WEI
VT
3I
O
3U
O
Commissioning 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 14
Glossary
117