Residential 100a service panel disconnect- backfed 100A ok?

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newservice

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Just looked at a job, Eaton 100A panel 24 space, no main breaker manufactured into the panel, just the 100A 2 pole backfed. Looks maybe alright, but, could get jostled loose in theory. Is this acceptable? I'm sure this is addressed elsewhere in the forum, just wondering if someone has the answer. Obvious the panel was intended as a subpanel..? Thx
 
newservice said:
Just looked at a job, Eaton 100A panel 24 space, no main breaker manufactured into the panel, just the 100A 2 pole backfed. Looks maybe alright, but, could get jostled loose in theory. Is this acceptable? I'm sure this is addressed elsewhere in the forum, just wondering if someone has the answer. Obvious the panel was intended as a subpanel..? Thx
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Yes, as long as the equipment is "suitable for use as service equipment" and has a hold down for the backfed MB.
 
electrofelon said:
Yes, as long as the equipment is "suitable for use as service equipment" and has a hold down for the backfed MB.
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Correct, 408.36(D) is the code reference for back-fed overcurrent devices.

Also you would want to verify that the panel has been listed for a 100 amp breaker to be connected to the bus.

Chris
 
Thank you, both. There is no hold down. Not sure I can get one, will check with Eaton on that and the panel being suitable for service equip and if there is a hold down available. Also, good point, on the 1ooA breaker being used to feed the panel from any bus stabs...
 
How old is the panel? If relatively new it likely can accept back feed breakers. Hold down kits may only work in specific positions within the panel though.
 
kwired said:
How old is the panel? If relatively new it likely can accept back feed breakers. Hold down kits may only work in specific positions within the panel though.
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Yeah it looks like one of the newer ones, aluminum bus, br style...Have never had to buy a hold down kit...do they make them? Will they work any spaces in the panel?
 
newservice said:
Yeah it looks like one of the newer ones, aluminum bus, br style...Have never had to buy a hold down kit...do they make them? Will they work any spaces in the panel?
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Can't tell you for certain, but most I have ever seen (any brand/model) the hold down kits only work at the main lug end of the panel. Some for more then just the first couple spaces - they considered the ability to have two mains and an interlock kit on some of them.
 
The Eaton/Cutler Hammer BR 100 amp main breaker panels are manufactured this way with a backfed main and hold down. If the hold down is missing, my guess is someone replaced the main breaker at some point and did not reinstall it.
 
peter d said:
The Eaton/Cutler Hammer BR 100 amp main breaker panels are manufactured this way with a backfed main and hold down. If the hold down is missing, my guess is someone replaced the main breaker at some point and did not reinstall it.
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Well, Eaton does make a panel with no breaker or main lugs even. I know what you're tallking about with the main breaker installed. That's what I was expecting to see. However someone had changed out the panel and not the old cable, and it was only long enough to get in the opposite side and half way down. So whether they butchered the panel to accomodate that or not IDK.
I think this is the panel, it does look like the bus was designed for a breaker at top left.
 

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newservice said:
Well, Eaton does make a panel with no breaker or main lugs even. I know what you're tallking about with the main breaker installed. That's what I was expecting to see. However someone had changed out the panel and not the old cable, and it was only long enough to get in the opposite side and half way down. So whether they butchered the panel to accomodate that or not IDK.
I think this is the panel, it does look like the bus was designed for a breaker at top left.
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Which side is the top?:)

If they sell them that way, then you would have to purchase separately a main breaker or plug on lug kit and a hold down accessory to secure it in place.

Add: the two right bus positions as we are looking at it appear to only have breaker fingers for what is the top side (as we are looking at it). I'd guess the main is supposed to go there and they don't want a branch breaker on the opposite side for whatever reasons.
 
kwired said:
Which side is the top?:)

If they sell them that way, then you would have to purchase separately a main breaker or plug on lug kit and a hold down accessory to secure it in place.

Add: the two right bus positions as we are looking at it appear to only have breaker fingers for what is the top side (as we are looking at it). I'd guess the main is supposed to go there and they don't want a branch breaker on the opposite side for whatever reasons.
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Yeah if they made that space for the main breaker, or service disco in this case, I agree it likely has to go there. Come to think of it I always wondered why they wont accept breakers across from the main, for whatever reason, and now it occurs to me it's because they don't want you knocking the main around...too close to it proximity wise. So I'll tell my customer its wrong the way it is, I'm good with that. That being said I'm not at all sure I could get a hold down for it in the main spot anyhow. Seeing that the old cloth entrance cable shows water leakage on the bottom of the panel I would say might be time for a ...wait for it.....new service.
 
newservice said:
Yeah if they made that space for the main breaker, or service disco in this case, I agree it likely has to go there. Come to think of it I always wondered why they wont accept breakers across from the main, for whatever reason, and now it occurs to me it's because they don't want you knocking the main around...too close to it proximity wise. So I'll tell my customer its wrong the way it is, I'm good with that. That being said I'm not at all sure I could get a hold down for it in the main spot anyhow. Seeing that the old cloth entrance cable shows water leakage on the bottom of the panel I would say might be time for a ...wait for it.....new service.
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Some panelboards you can mount another breaker across from a backfed style main. Ones that come to mind are 100 amp QO loadcenters with a three pole main breaker.

If you get a NQ panel (accepts bolt on breakers) you can put a back fed bolt on main in any position you wish, a bolt on breaker doesn't need a hold down kit.
 
The panel in the pic is made for a 100a breaker to be placed on the cut buss at the top of the panel


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Except horizontal, unless you are in Canada.
If the breaker throws from the centerline of the bus to the nearest edge, only one horizontal orientation (like the picture ended up displaying) will have up being ON.
 
GoldDigger said:
Except horizontal, unless you are in Canada.
If the breaker throws from the centerline of the bus to the nearest edge, only one horizontal orientation (like the picture ended up displaying) will have up being ON.
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We can mount any panelboard horizontal we just give up use of half the positions.
 
iwire said:
We can mount any panelboard horizontal we just give up use of half the positions.
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And in the case pictured, the main will only fit in one way, so that would be the one you lose in one orientation.
We were not talking about using the panel as MLO without a backfeed breaker.
 
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