In a circuit breaker if the insulation resistance between phase terminal and earthed frame is less than the specified limit, the probable cause could be
A. moisture
B. dirty insulation surface
C. carbon or copper particles sticking to the internal surface
D. any of the above.
Answer:D
In a circuit breaker if the insulation resistance between phase terminal and earthed frame is less than the specified limit, the probable cause could be
A. moisture B. dirty insulation surface C. carbon or copper particles sticking to the internal surface D. any of the above.