Sequence of operation of isolator and circuit breaker while opening and closing

Sequence of operation of isolator and circuit breaker while opening and closing
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Answer :

Sequence of operation of Isolator and C.B while opening & closing is as below:

 While Opening: 

 1. Open circuit breaker

 2. Open Isolator

 3. Close earthing switch

 While Closing: 

 1. Ensure circuit breaker is open

 2. Open earthing switch

 3. Close isolator

 4. Close circuit breaker


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