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Section 1: Introduction
Series NRX with PXR - type RF low voltage power (air) circuit breakers instruction manual
MN013002ENH03 September 2016 www.eaton.com
Section 1: Introduction
Purpose
This instructional manual is intended to generally cover the
installation, operation, and maintenance of Series NRX
TM
low voltage power (air) circuit breakers and drawout cas-
settes. Basic dimensional information is provided for the
installation of both the circuit breaker and cassette.
Refer to other documentation for more specific details.
1.
MN013003EN: Operating Manual for Series NRX PXR
20/25
1.
AD013001EN: PXR 20/25 Time Current Curves
2. TD013001EN: Wiring Diagrams for PXR 20/25
3. Accessory field installation instruction leaflets (IL) dedi-
cated to specific items are available for download at
www.eaton.com/seriesnrx.
4. Visit www.eaton.com/seriesnrx for additional support
documentation.
Safety
All safety codes, safety standards, and/or regulations must
be strictly observed in the installation, operation, and main-
tenance of this equipment.
WARNING
The warnings and cautions included as part of the pro-
cedural steps in this manual are for personnel safety
and protection of equipment from damage. This exam-
ple of a typical Warning is intended to familiarize per-
sonnel with the style of presentation.
IMPORTANT
Please read and understand these instructions before
attempting to unpack, install, operate, or maintain this
equipment. Study the breaker and its mechanism carefully
before attempting to operate it on an energized circuit.
All possible contingencies that may arise during installation,
operation, or maintenance, and all details and variations
of this equipment do not purport to be covered by these
instructions. If further information is desired by purchaser
regarding a particular installation, operation, or maintenance
of particular equipment, contact the local Eaton representa-
tive.
WARNING
Series NRX circuit breakers are provided with safety fea-
tures. Nevertheless, the voltages, currents, and power
levels available around operational equipment are
extremely dangerous. Under no circumstances should
interlocks and other safety features be made inopera-
tive, as this may result in death, bodily injury, or prop-
erty damage.
Safe practices
To protect personnel associated with the installation, opera-
tion, and maintenance of this equipment, the following prac-
tices must be followed.
1.
Only qualified electrical personnel familiar with the
equipment, its operation, and the associated hazards
should be permitted to work on, install, or operate the
equipment.
5. Always
be
certain that the primary and secondary cir-
cuits are de-energized or the circuit breaker is open and
removed to a safe work location before attempting any
maintenance.
6. For maximum safety, only insert an open, completely
assembled breaker into an energized cell.
7. Always
ensure that drawout circuit breakers are in one
of their designed cell positions, such as CONNECT,
TEST, DISCONNECT, or WITHDRAWN. A circuit breaker
permitted to remain in an intermediate position could
result in control circuits being improperly connected,
resulting in electrical failures.
Qualified personnel
For the purpose of operating and maintaining power circuit
breakers, a person should not be considered qualified if
the individual is not thoroughly trained in the operation of
the circuit breaker and how it interfaces with the assembly
in which it is used. In addition, the individual should have
knowledge of the connected loads.
For the purpose of installing and inspecting circuit breakers
and their associated assembly, a qualified person should
also be trained with respect to the hazards inherent to
working with electricity and the proper way to perform such
work. The individual should be able to de-energize, clear,
and tag circuits in accordance with established safety prac-
tices.
General information
The series NRX range of low voltage power (air) circuit
breakers and switch-disconnectors are designed, manufac-
tured, and tested for use in both switchboard and metal-
enclosed switchgear assemblies in accordance with UL489
and IEC 60947-2 requirements. The series NRX range is
manufactured and tested in an ISO 9001 certified facility.
Series NRX circuit breakers and switch-disconnects are
available in fixed and drawout mounting configurations and
offer a variety of different connection solutions. The fixed
configuration is designed for rear bus connections. The
drawout version, in conjunction with its drawout cassette,
is a through-the-door design having three breaker posi-
tions with the compartment door closed (CONNECT, TEST,
DISCONNECT) and one position out of its compartment on
extension rails (WITHDRAWN). A drawout cassette is also
designed for rear bus connections. Continuous current rat-
ings from 800 - 4000 A and interuption capacities up to
105 kA are available depending on the applicable standard.
All series NRX circuit breakers are 100 percent rated.
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