What items are you to check when working on a circuit breaker?

What items are you to check when working on a circuit  breaker?
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1 Answer

Answer :

Check the operating mechanism for smooth operation, check  the contacts for pitting, check the terminals for tightness and  corrosion, check the mounting hardware for tightness and wear,  check all components for wear, and check the entire circuit breaker  for cleanliness.
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Which of the following problems will occur if the circuit breaker of the incoming alternator is closed and it is 180° out of phase with the loaded alternator when paralleling? A. The rotor of the loaded alternator will hunt. B. Severe cross currents will occur which could cause damage. C. The rotor of the incoming alternator will stop. D. Both alternators will parallel 180° out of phase.

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Last Answer : Answer: C

An alternator is being paralleled with one on the line. At the INSTANT the circuit breaker is closed, the frequency of the incoming alternator will normally _____________. A. increase B. not change C. decrease D. be exactly 60 hertz

Description : An alternator is being paralleled with one on the line. At the INSTANT the circuit breaker is closed, the frequency of the incoming alternator will normally _____________. A. increase B. not change C. decrease D. be exactly 60 hertz

Last Answer : Answer: C