43
User Manual
MN013016EN
Effective July 2022
Magnum PXR and Power Defense SB low
voltage power circuit breakers user manual
EATON
www.eaton.com
Section 6: Fixed circuit breaker
General
Section 3 discussed topics and features common to all Magnum
PXR and PD-SB circuit breakers, no matter what the mounting
configuration or type . In this section, features unique to the fixed
configuration not covered elsewhere are covered . The installation
of a fixed circuit breaker was discussed in Section 2 . If necessary,
review that information, because it will not be repeated here .
Fixed circuit breaker dimensions
The standard fixed circuit breaker is supplied with horizontally
mounted primary connections (
) . Optional vertical primary
adapters are available for different bus configurations . Drawings and
dimensions associated with all circuit breakers, drawout cassettes,
and any appropriate primary bus connections can be found in the
technical product guide (PA013006EN), available on the website at
www .eaton .com/magnumpxr .
Figure 71. Fixed narrow frame circuit breaker with available
vertical adapter shown
Section 7: Importance of maintenance
General
Magnum PXR and PD-SB circuit breakers are manufactured under a
high degree of quality control, with the best available materials, and
with a high degree of tooling for accuracy and part interchangeability .
Design tests and actual experience show them to have durability
well beyond minimum standards requirements . However, because of
the variability of application conditions and the great dependence
placed upon these circuit breakers for protection and the assurance
of service continuity, Eaton recommends that inspection and
maintenance activities take place on a regularly scheduled basis .
This section explains what Magnum PXR and PD-SB components
need to be maintained, when they should be inspected, and step-
by-step procedures for completing required inspections and tests .
The following maintenance recommendations apply to all families of
Magnum PXR and PD-SB breakers .
Eaton’s history of producing high-quality electrical components has
made Eaton a leader in the industry and a contributing member
of many governing standards agencies . The basis for the information
provided in this guide comes from the National Electrical
Manufacturers Association (NEMA) standard, NEMA AB4, and the
National Fire Protection Association (NFPA) standard, NFPA 70B . If
further assistance or information is required, please contact Eaton
Electrical Services and Systems at 1-877-386-2273 (1-877-ETN-
CARE) .
It is recommended that maintenance record sheets be completed
each time maintenance is performed on the circuit breaker . Careful
and accurate documentation of all maintenance activities provides a
valuable historical reference on equipment over time . Examples are
provided on
and
.
This document cannot, and is not intended to, ensure proper
electrical performance of a Magnum PXR and PD-SB breaker that
has been modified in any way that is not authorized by Eaton .
Safety precautions
m
WARNING
FAILURE TO INSPECT, CLEAN, AND MAINTAIN CIRCUIT BREAKERS CAN
REDUCE EQUIPMENT LIFE OR CAUSE THE EQUIPMENT NOT TO OPERATE
PROPERLY UNDER FAULT CONDITIONS. THIS COULD RESULT IN
EQUIPMENT DAMAGE, BODILY HARM, OR EVEN DEATH.
Only workers with electrical training and familiarity with power
circuit breakers and their associated hazards should perform work
on Magnum PXR and PD-SB circuit breakers . Workers should also
become familiar with the specifics associated with Magnum PXR
and PD-SB circuit breakers as presented in this maintenance section .
Be sure to follow all safety guidelines and wear proper personal
protective equipment when performing maintenance on a circuit
breaker .
Unless otherwise specified in this guide, inspection, preventative
maintenance, and testing must always be performed on equipment
that is in an electrically-safe working condition (as defined in Article
120 of NFPA 70E-2015) and at a distance beyond the arc flash
boundary of energized electrical conductors . Verify that there is
no voltage present on incoming terminals (or on control power
terminals, if present) and between these terminals and ground to
positively ascertain that the equipment is totally in an electrically
safe working condition . The disconnecting or isolating means on the
line side of the isolation devices being checked or tested should
be in the open state to assure that the equipment will remain in
an electrically safe working condition during these procedures by
exercising approved Lock-Out-Tag-Out procedures . Refer to the
Hazardous Energy Control procedures as described in OSHA and
NFPA 70C-2015, Article 120 .2 (D) for clarification .
Low voltage AC power circuit breakers should be installed, operated,
and maintained by qualified personnel as defined by OSHA
Horizontal
connection
Optional
vertical
adapter
