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#7451 - 02/05/02 08:20 PM thermal trip settings on breakers
menegt Offline

Registered: 01/09/02
Posts: 35
Loc: sacramento, ca
What is the rule of thumb in setting the trip settings and time delay trip on a breaker? Any help would be appreciated.

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#7452 - 02/06/02 05:39 AM Re: thermal trip settings on breakers
JBD Offline

Registered: 07/12/01
Posts: 599
Loc: WI, USA
What type of breaker? Molded case with adjustable thermal-magnetics? Molded case with complete solid-state trip elements covering long, short and instantaneous trips? Air-frame power style with withstand ratings?

On large projects the trip settings are usually determined by some type of time-current coordination study.

On small projects the manufacturer usually has typical settings for solid-state trip elements that will mimic thermal-magnetic curves.


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