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#169143 - 09/27/07 04:07 AM Breaker Rating, Iu vs In
SteveFehr Offline
Member

Registered: 03/19/05
Posts: 1192
Loc: 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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#169227 - 09/29/07 03:36 AM Re: Breaker Rating, Iu vs In [Re: SteveFehr]
Scott35 Offline

Broom Pusher and
Member

Registered: 10/19/00
Posts: 2724
Loc: 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!

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#169251 - 09/29/07 07:46 PM Re: Breaker Rating, Iu vs In [Re: Scott35]
SteveFehr Offline
Member

Registered: 03/19/05
Posts: 1192
Loc: Chesapeake, VA
That's my working assumption, too, Scott. I hate guessing about things like this, though.

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