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Fixed MV Circuit Breaker

Fixed MV Circuit Breaker

Fixed MV Circuit Breaker

Dear Forum Members,
I understand that the only means to safely isolate a medium voltage circuit breaker is to take it out and padlocked it in the test position. What about fixed circuit breakers? Could the spring charged mechanism be used to safely isolate a fixed circuit breaker? A circuit breaker which is not charged to a ready to close position would basically not close. Any insight?

RE: Fixed MV Circuit Breaker

In this case, should be installed isolation switches (disconnector) series with a breaker.

RE: Fixed MV Circuit Breaker

A vacuum breaker can't be used as safety isolation no matter how you lock out the mechanism. An upstream breaker needs to be racked out or there needs to be a switch in series.

RE: Fixed MV Circuit Breaker

What about SF6?

RE: Fixed MV Circuit Breaker

same rules apply, physical open space is required.

RE: Fixed MV Circuit Breaker

In GIS must be installed a guaranteed indicator of position of isolated switch.

RE: Fixed MV Circuit Breaker

At least in the US, a "visible break" is required. And probably shorts and grounds in many cases. "If it isn't grounded, it isn't dead."

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