GE Power Break, User Manual

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Power Break ® Circuit Breakers
Chapter 2. Breaker Operation
8
Figure 12. Wiring diagram for MicroVersaTrip and MicroVersaTrip
RMS-9 trip units with ground fault on a top-fed four-wire load.
Figure 13. Wiring diagram for MicroVersaTrip and MicroVersaTrip
RMS-9 trip units with ground fault on a bottom-fed four-wire load.
MicroVersaTrip RMS-9 Trip Units
The trip units on MicroVersaTrip RMS-9-equipped break-
ers are not interchangeable. The breaker rating may be
adjusted by changing the rating plug installed in the face
of the trip unit. See GEH-5369 and GEH-5371 for instruc-
tions.
MicroVersaTrip Trip Units
MicroVersaTrip-equipped breakers were ordered complete
or as a frame and trip unit only. Some trip units and
frames have rejection schemes to prevent mismatching of
functions.
The limits of interchangeability are as follows:
• High short-time or H-function trip units may not be
used in frames that are not wired for H function
(special CTs).
• Special trip units for AK breakers with the M (no
instantaneous) function may not be used with Power
Break breakers.
Refer to GEH-4657 for installation or replacement of
MicroVersaTrip trip units with remote overload indication
and for recommended wiring for zone-selective interlock.
To change or install trip units without remote indication,
use the following procedure.
W W
W WA
A
A AR
R
R RN
N
N NIIIIN
N
N NG
G
G G:::: The circuit breaker must be removed from
the electrical system before attempting any operations
that involve removing the breaker’s cover.
1 1 1 1.... Remove the four cover-mounting screws and remove
the top cover. On motor-operated breakers, remove
only the top cover to replace the trip unit.
2 2 2 2.... Remove the trip unit as follows:
a a a a.... Push in the trip unit-cover interlock, as illustrated
in Figure 14.
b b b b.... Lift the trip unit off the mounting plate and ter-
minal plug.
ccc c.... The trip unit-cover interlock will now swing out
and lock over the base to prevent reinstallation of
the breaker cover when no trip unit is installed.
Figure 14. Releasing the trip unit cover interlock to remove or install
the trip unit.