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#28266 - 08/15/03 08:49 AM Opening switch under load?
Redsy Offline

Registered: 03/28/01
Posts: 2138
Loc: Bucks County PA
Several times, people have expressed concern about occasionally (especially in an emergency)opening a feeder circuit breaker or an equipment disconnect switch under load.
As long as it is properly rated, and it is not an isolation switch, I don't see why there should be any problem.
Your thoughts, please?

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#28267 - 08/15/03 10:51 AM Re: Opening switch under load?
wolfdog Offline

Registered: 10/24/01
Posts: 135
Loc: Dallas,TX
I had a similar discussion on an air conditioning web site.
Disconnects for a/c and motor equipment are horsepower rated and sized accordingly to allow for disconnect operation under load.

[This message has been edited by wolfdog (edited 08-15-2003).]

#28268 - 08/15/03 01:55 PM Re: Opening switch under load?
pauluk Offline

Registered: 08/11/01
Posts: 7693
Loc: Norfolk, England
And wouldn't an HP-rated disconnect also be designed to break the load of a stalled motor?


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