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WEG Molded Case Circuit Breakers - User’s Manual
8
WARNING
Voltages in energized equipment can cause severe personal injuryordeath.
Before inspecting the circuit breaker in an electrical system, make sure
the circuit breakeris switched to theoff position and thatthereisnovoltage
presentwhere workisbeing performed. Special attention should be paid to
reverse feed applications to ensure no voltageis present.
CAUTION
Some commercial cleaning agents will damage the nameplatesormolded
parts. Make sure that cleaning agentsor solvents usedto clean the circuit
breaker are suitable or the job.
1. Remove dust, dirt, soot, grease, or moisture from the surface of the circuit
breaker using a lint-free dry cloth, brush, or vacuum cleaner. Do not blow
debris into circuit breaker. If contamination is found, look for the source and
eliminate the problem.
2. Switch circuit breaker to ON and OFF several times to be sure that the
mechanical linkages are free and do not bind. If mechanical linkages are not
free, replace circuit breaker.
3. With the circuit breaker in the ON position, press the PUSH-TO-TRIP button
to mechanically trip the circuit breaker.Trip, reset, and switch circuit breaker
ON several times. If mechanism does not reset each time the circuit breaker is
tripped, replace the circuit breaker.
4. Check base, cover, and operating handle for cracks, chipping, and discoloration.
Circuit breakers should be replaced if cracks or severe discoloration is found.
5. Check terminals and connectors for looseness or signs of overheating.
Overheating will show as discoloration, melting, or blistering of conductor
insulation, or as pitting or melting of conductor surfaces due to arcing. If
there is no evidence of overheating or looseness,donot disturb or tighten
the connections. If there is evidence of overheating, terminations should be
cleaned or replaced. Before re-energizing the circuit breaker, all terminations
and cable should be refurbished to the condition when originally installed.
6. Check circuit breaker mounting hardware, and tighten if necessary.
7. Check area where circuit breaker is installed for any safety hazards, including
personal safety and fire hazards. Exposure to certain types of chemicals can
cause deterioration of electrical connections.
