After a black out the emergency generator comes on; On restoring the main supply we are closing the circuit breaker of the main generator without bothering about synchronizing. How is this possible?

After a black out the emergency generator comes on; On restoring the main supply we are closing the circuit breaker of the main generator without bothering about synchronizing. How is this possible?
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1 Answer

Answer :

There is a power link connection breaker between the main generator and the emergency generator. During black out, this breaker trips. The emergency generator starts and its breaker closes and feeds only the emergency loads. During restoration, the main generator is started again and its breaker is closed. As the link breaker is still open, there is no paralleling between main and emergency generator. Ask E/O for more details.
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