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mathew stouffer
05-18-2010, 11:13 AM
The disconnect was a 200amp with a 100 amp breaker located above and below the disconnect. The 2 100amp supply two interior panels. On the rating information it indicates the max breaker on the upper aspect of the panel should not exceed 70amps. Is this installation incorrect?

Bill Kriegh
05-18-2010, 04:32 PM
I'm having trouble with what part of the label that says a 100 AMP breaker can only be installed in the bottom position you don't understand. Instructions don't get much simpler.

Jerry Peck
05-18-2010, 04:39 PM
I'm having trouble with what part of the label that says a 100 AMP breaker can only be installed in the bottom position you don't understand. Instructions don't get much simpler.


Go back and read those instructions again. That is not what it says.

That is what it implies.

Concentrate your attention onto the word "branch" and you will see what I am referring to.

mathew stouffer
05-18-2010, 06:12 PM
So it is correct.

Jerry Peck
05-18-2010, 06:40 PM
The way I read it is:

250 amp maximum rating of the mains

If you look at the photo you will see the center bus bar mounted and visible to the left of the breakers.

The mains that is referring to is the quad breaker with the service entrance conductors which go out to the right, then tuck back down and behind the bus bar.

That main is limited to a rating of 250 amp maximum.

Below that is a position which is rated for 100 amps maximum.

The rest depends on what is not shown in the schematic at right of your photo and is cut off.

I would suspect ... that the (referring back to the photo) breaker locations above that main is for branch circuit breakers. The breaker section at the top would be for branch circuit breakers.

Those breaker tabs would rated for 70 amps maximum.

What I was pointing out to Bill was that what he said the label and instructions said was incorrect and that it was not as simple as he said ... but that his outcome was correct.

It is like "quoting" someone and then paraphrase what was said - you may be right about the intent but you should quote it and not paraphrase it.

Anyway, that was my take on the way Bill said it.

Do you have a photo showing the schematic?

mathew stouffer
05-18-2010, 07:55 PM
Of course not, I am not that smart. But thanks for the info.

H.G. Watson, Sr.
05-18-2010, 11:57 PM
MS,

See the attached DWG 1993.
Not exactly the same (more recent) but close.
No, not right, as BK indicated. Just one 100 amp bottom position - nearest feed-through lugs. Others limited to 70 amps. You can call Schnieder Electric/Square D for older drawing and verification if you'd like.

HTH.

H.G.

Jerry Peck
05-19-2010, 03:06 PM
H.G.,

Thanks for the drawing, it shows what Mat's label was stating.

Mat,

I've highlighted the drawing H.G. provided with red to indicate what is being said - which is what was stated in the posts above.

Some of the red is not as easy to see as I thought it would be.