Glossary
under frequency alarm The alarm signal from the trip unit
when the system drops below a user-specified line frequency
value.
V
voltage balance See Phase Balance.
VT Voltage transformer. See PT.
W, X, Y
waveform The graphical depiction of the current or voltage over
time.
waveform capture The function of saving the measurement of
the current or voltage over one cycle.
WinPM™ Windows-based electrical distribution and communi-
cations software designed for personal computers. Through com-
munications drivers, WinPM software collects and displays real-
time data from ACCESS field devices. WinPM also monitors and
displays historical data, minimum and maximum data, and wave-
form data. In addition, WinPM can deliver its data to other com-
patible Windows applications in real-time through dynamic data
exchange (DDE).
Z
zone interlock The interconnecting of several circuit protection
devices, to protect a specified portion of a power system, and
coordinate in timing the action of those devices.
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