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6. Monitoring and testing
Power XPert® release triP unit for MagnuM PXr circuit breakers
MN013015EN January 2022 www.eaton.com
Figure 22. On-board test features.
For detailed information, please see the Quick Start Guide
supplied with the Power Xpert Protection Manager (PXPM)
software.
6.5 Testing for ground fault trip units – primary
injection
Many local or country building codes require that any ground
fault protection system be performance tested when first
installed. Conduct tests in accordance with the approved
instructions provided with the equipment. Make a written
record of this test and make the results available to the
authority having inspection jurisdiction.
For basic performance requirements stipulated by the NEC
and UL Standard No. 1053, the test requires that certain
minimum instructions must accompany each ground fault
protection system. These statements, plus a copy of the
record forms, are included in Section 10 - Records and
forms.
The interconnected system must be evaluated only by
qualified personnel and in accordance with the equipment
assembler’s detailed instructions.
WARNING
Electrical shock or burn injury can occur when working
on power systems. Always turn off the main power that
is supplying the circuit breaker before conducting tests.
Test out of the cell, if possible.
To avoid improper operations following apparently correct
simulated test operations, the polarity of the neutral sensor
connections (if used) must agree with the equipment assem-
bler’s detailed instructions. Where a question exists, consult
the specifying engineer and/or equipment assembler.
Verify the grounding points of the system using high voltage
testers and resistance bridges to ensure that ground paths
do not exist that could bypass the sensors.
Use a low voltage (0 to 24 volt), high-current, AC source to
apply a test current of 125% of the ground pickup setting
through one phase of the circuit breaker. This should cause
the circuit breaker to trip in less than one second and
operate the alarm indicator, if one is supplied. Reset the
circuit breaker and the alarm indicator. Repeat the test on
the other two phases.
Apply the same current as described above through one
phase of the circuit breaker, returning through the neutral
sensor if a neutral sensor is used. The breaker should not
trip and the alarm indicator, if one is supplied, should not
operate. Repeat the test on the other two phases.
6.6 Testing within the switchgear
When the Magnum PXR is integrated within the switch-
gear, the unique features of the PXR trip unit should be
considered.