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From: Don Kuenz <g@crcomp.net>
Newsgroups: sci.electronics.design
Subject: Re: AC switch fault current philosophy
Date: Thu, 28 Dec 2017 18:45:52 -0000 (UTC)
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Piglet <erichpwagner@hotmail.com> wrote:
> When designing a semiconductor based switch for AC mains power which is
> the better philosophy to handling a load side short circuit:
>
> 1. Use devices rugged enough to pass the fault current and allow the
> upstream breaker or fuse to operate as usual if the switch had been
> mechanical;
>
> 2. Switch off fast enough to break the current before damage occurs and
> retry a second or two later?
>

You might limit the current and trip the mains breaker to cope with the
short. That way you simultaneously protect the shorted device and send
users a dramatic message that something's wrong.

Thank you,

--
Don Kuenz, KB7RPU