Why synchronizing scheme has been adopted? What are interlocks provided?

Why synchronizing scheme has been adopted? What are interlocks provided?  
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1 Answer

Answer :

To check running and incoming buses, which are going to be interconnected are in synchronism with each other.

Interlocks

1. Synch selector.

2. Only one breaker can operate at a time.

3. Master synch relay contact should available (bypass will bypass this synch contact).

Bypass facility is provided to close the breaker on dead bus only. 
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