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clock, and uses the Gregorian calendar. It is used for
aeroplane and ship navigation, where it is also sometimes
known by the military name, "Zulu time." "Zulu" in the
phonetic alphabet stands for "Z", which stands for
longitude zero.
UV
Undervoltage
WEI
Weak end infeed logic
VT
Voltage transformer
X.21
A digital signalling interface primarily used for telecom
equipment
3I
O
Three times zero-sequence current.Often referred to as the
residual or the earth-fault current
3U
O
Three times the zero sequence voltage. Often referred to
as the residual voltage or the neutral point voltage
1MRK 511 393-UEN A
Section 9
Glossary
670 series 2.2 IEC
61
Communication protocol manual