ABB REG670 Commissioning Manual page 299

1MRK 502 073-UEN A
Generator protection REG670 2.2 IEC and Injection equipment REX060, REX061, REX062
Commissioning manual
UV
WEI
VT
X.21
3I
O
3U
O
phonetic alphabet stands for "Z", which stands for
longitude zero.
Undervoltage
Weak end infeed logic
Voltage transformer
A digital signalling interface primarily used for telecom
equipment
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 17
Glossary
293