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Instruction Leaflet
IL0131154EN
Effective August 2021
Neutral current sensors
Magnum PXR ACB trip units
EATON
www.eaton.com
Section 2: Performance testing for ground
fault circuit breakers
Please consult Instruction Leaflet number IL012125EN for general
instructions to aid you in ground fault testing of circuit breakers with
PXR electronic trip units.
General test instructions
The interconnect system shall be evaluated in accordance with the
equipment assembler’s detailed instruction by qualified personnel.
The polarity of the neutral sensor connection (if used) must agree
with equipment assembler’s detailed instructions to avoid improper
operations following apparently correct simulated test operations.
Where a question exists, consult the specifying engineer and/or
equipment assembler.
The grounding points of the system shall be verified to determine
that ground paths do not exist that would bypass the sensors. High-
voltage testers and resistance bridges may be used.
m
IMPORTANT
THE POLARITY OF THE SENSOR CONNECTIONS IS CRITICAL. ALWAYS
OBSERVE THE POLARITY MARKINGS ON THE INSTALLATION DRAWINGS.
THE POLARITY MARKINGS ARE IDENTIFIED AS WHITE DOTS ON THE
TRANSFORMERS. TO INSURE CORRECT GROUND FAULT EQUIPMENT
PERFORMANCE, CONDUCT FIELD TESTS TO COMPLY WITH NATIONAL
ELECTRIC CODE REQUIREMENTS UNDER ARTICLE 230-95-C. SEE
PERFORMANCE TESTING INSTRUCTIONS ON IL012125EN.
ote:
N
Since the ground fault circuit breakers derive their operating power
from the phase current and not from the neutral current, passing current
through the neutral sensor only will not properly test the ground fault feature.
