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#2039 - 06/16/01 09:46 AM How breaker works?
Mike Shn Offline

Registered: 06/13/01
Posts: 26
Loc: New York
Can someone explain to me or give me a link to about breaker?

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#2040 - 06/16/01 12:25 PM Re: How breaker works?
Tom Offline

Registered: 01/01/01
Posts: 1069
Loc: Shinnston, WV USA
I don't know of any links, so I'll give this a shot.

most breakers that you're likely to encounter are thermal-magnetic.

The thermal part has a bi-metallic strip. Since the 2 metals expand & contract at different rates, the strip will bend as it heats up. If it bends enough, it will engage a trip mechanism and turn off the current. This is for overloads.

The magnetic part consists of a small coil in series with the load. When enough current flows, the magnetic field is strong enough to acuate the trip mechanism. This part is for short circuits, ground faults or any other large current flow.

Few things are harder to put up with than the annoyance of a good example.

#2041 - 06/16/01 12:45 PM Re: How breaker works?
RICK 44 Offline
Junior Member

Registered: 06/08/01
Posts: 5
Look around in this site, think youll find more info than you want.

#2042 - 06/17/01 09:05 AM Re: How breaker works?
Phil H Offline

Registered: 04/14/01
Posts: 24
Loc: Tujunga, CA
Square D has this about breakers: Overcurrent Protection
The 23 page adobe acrobat file is about 1.4mb.

[This message has been edited by Phil H (edited 06-17-2001).]


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