15
User Manual
MN013016EN
Effective July 2022
Magnum PXR and Power Defense SB low
voltage power circuit breakers user manual
EATON
www.eaton.com
Figure 14. Typical fixed Magnum PXR circuit breaker
Circuit breaker terminals have holes for making bolted horizontal
primary bus connections . Adapters are available for making vertical
primary bus connections . Secondary connections can be made
through standard terminal blocks or a special connector compatible
with the drawout circuit breaker’s type secondary connector . Both
secondary connection devices are mounted at the top front of the
circuit breaker .
The fixed circuit breaker frame has two mounting feet, one on each
side, to permit the fixed circuit breaker to be securely mounted .
Each mounting foot has two slotted mounting holes that are used to
bolt the circuit breaker securely in place . Use either M10 or 3/8-inch
bolts for this purpose . Refer to the dimensional drawings referred
to in Section 6 (Fixed circuit breakers) for circuit breaker and bus
stab dimensions .
Circuit breaker operation
Circuit breakers should be operated manually and/or electrically
before they are put into service . This can be done during the
installation process or some later date prior to startup . To check
circuit breaker operation, follow the operational procedures outlined
in Section 3 for both manually operated and electrically operated
circuit breakers .
Section 3: Circuit breaker description
and operation
Introduction
Magnum PXR and PD-SB circuit breakers are available in both
drawout and fixed mounting configurations (
) . A majority of features are common to all configurations, and
will be discussed in this section . The mounting features unique to
the drawout and fixed configurations will be covered individually in
Sections 5 and 6 respectively .
Controls and indicators for both drawout and fixed circuit breakers
are functionally grouped on the front of the circuit breaker . The front
escutcheon (faceplate) is common for all frame sizes up to 6000A
(up to 5000A for PD-SB) . Double frame circuit breakers use six (or
eight) sets of rear primary connections; these circuit breakers are
available from the factory with several different phase sequences,
distinguishable by the sixth character in the model number . The
phase sequence is also labeled on the rear of the circuit breaker
(
) . For these drawout breakers, phase sequence labels
are also supplied with the cassette and must be applied by the
switchgear builder . Circuit breakers with different phase sequences
are not interchangeable . Drawout breakers with differing phase
sequence are prevented from insertion into the cassette by properly
assembled rejection key plates (see
Section 2) .
Mounting foot
