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Breaker Rating, Iu vs In #169143
09/27/07 07:07 AM
09/27/07 07:07 AM
S
SteveFehr  Offline OP
Member
Joined: Mar 2005
Posts: 1,213
Chesapeake, VA
I'm used to seeing either Iu or In, or the two identical, but I recently came across a molded case breaker (GE D125) that had an Iu=125A and In=100A, (adjustible from 75-100A). It's not a plug, it's built into the breaker and can't be changed beyond the pot. What, exactly, does this mean? As I understand it, Iu=125A means the contacts are rated for 125A... but with a 100A trip setting, why does that matter in the least? Why would they even bother labeling it? Am I missing something here?

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Re: Breaker Rating, Iu vs In [Re: SteveFehr] #169227
09/29/07 06:36 AM
09/29/07 06:36 AM
Scott35  Offline

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Joined: Oct 2000
Posts: 2,708
Anaheim, CA. USA
Could this be a 125 Amp frame, with a 100 Amp trip?

Kind of looks that way from the Spec # (GE D 125), but who knows.

Let me check the GE catalog, then reply later.

Scott


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
Re: Breaker Rating, Iu vs In [Re: Scott35] #169251
09/29/07 10:46 PM
09/29/07 10:46 PM
S
SteveFehr  Offline OP
Member
Joined: Mar 2005
Posts: 1,213
Chesapeake, VA
That's my working assumption, too, Scott. I hate guessing about things like this, though.


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