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WEG Molded Case Circuit Breakers - User’s Manual
10
WARNING
The voltages in energized equipment can cause severe personal injury or
death. Before inspecting thecircuit breaker in an electrical system, make
sure the circuit breaker is switched to the off position and that there is no
voltage present where work is to be performed. Special attention should be
to reverse feed applications to ensure no voltage is present.
Caution
Some commercial cleaning agents will damage the nameplates or molded
parts. Make sure that cleaning agents or solvents used to clean the circuit
breaker are suitable for 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 operate freely and do not bind. If mechanical linkages do
not operate freely, 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, operating handle, and handle barrier for cracks, chipping,
and discoloration. Circuit breakers should be replaced if cracks or severe
discoloration is found.
5. Check wire connecting terminals and other type busbar 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 over heating or
looseness, do not 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
originally installed condition.
6. Check circuit breaker mounting hardware, and tighten if necessary.
7. Exposure to certain types of chemical scan cause deterioration of electrical
connections. Check area where circuit breaker is installed for any safety
hazards, including personal safety and fire hazards and take required
precautionary actions.
