GE Industrial Solutions MicroVersaTrip PM - Manual (Page 35)

MicroVersaTrip Plus™ and MicroVersaTrip PM™ Trip Units
Chapter 3. Metering Mode
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3-1 Overview
The metering mode displays parameter values for
that part of the electrical system controlled by the
breaker’s MicroVersaTrip Plus or MicroVersaTrip
PM Trip Unit. Both currents and voltages are com-
puted as true rms values. There is no loss of accuracy
even in the presence of high levels of harmonics. All
metering displays are updated once each second.
Accuracies and resolutions are described in Section
1-8 and Table 7.
All values except frequency are displayed to three
significant figures. For example, phase currents
might be displayed as 60.7
AMPS
, 492
AMPS
, or 1.22
KA .
The Trip Unit metering displays are appropriate to
the actual configuration ordered. All MicroVersa-
Trip Plus and MicroVersaTrip PM Trip Units
include current metering. Two configurations of the
MicroVersaTrip PM Trip Units (with PM and M
suffixes in their catalog numbers) have the full
complement of metering displays.
The Trip Unit must be provided with control power
to display metered values. This can come from inter-
nal battery power, from a MicroVersaTrip Portable
Power pack, from an external +24 Vdc power supply,
or by energizing the breaker to at least 20% of its
sensor load.
3-2 Metering Mode Operation
Metering mode is reached by pressing FUNCTION
until METER appears in the upper-right corner of the
display. Metering mode always begins with the phase
currents. The sequence in which the metered values
appear is illustrated in Figure 47.
Figure 47. Trip Unit metering mode function flow.