GE Industrial Solutions WavePro Low-Voltage Power Circuit Breakers - Manual (Page 29)

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 computed as true rms val-
ues. 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 6.
All values except frequency are displayed to three signifi-
cant figures. For example, phase currents might be dis-
played as
60.7 AMPS , 492 AMPS , or 1.22 KA .
The Trip Unit metering displays are appropriate to the
actual configuration ordered. All MicroVersaTrip 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 auxiliary power to
display metered values. This can come from internal bat-
tery 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 41.
Figure 41. Trip Unit metering mode function flow.