200 amp main breaker panel used as 100 amp sub panel

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Patoneil

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Builder
I used a 200 amp homeline main breaker panel as a 100 amp sub panel. The sub panel is protected by 100 amp breaker in the main panel.

I thought that this was ok since the 200 amp breaker in the sub panel was just acting as a disconnect. My inspector thinks this is a code violation.

Is it really a code violation? If so, how difficult is it to convert to main lug?
 
Your inspector is wrong. If the 200 amp panel didn't have a breaker would that not be compliant? The panel and the wire are protected by the 100 amp breaker and the fact that the panel has a 200 amp breaker is not significant.
 
I think it is compliant. The basic rule is that everything (i.e., your subpanel) must be protected against overcurrent by a device rated no higher than its (i.e., your subpanel's) own rating. You met that requirement.
 
(NOTE TO SELF: Always type up your own response - in Word - before approving a new thread. That way, somebody else cannot sneak in and post a reply before you are ready. ;) )
 
Patoneil said:
I used a 200 amp homeline main breaker panel as a 100 amp sub panel. The sub panel is protected by 100 amp breaker in the main panel.

I thought that this was ok since the 200 amp breaker in the sub panel was just acting as a disconnect. My inspector thinks this is a code violation.

Is it really a code violation? If so, how difficult is it to convert to main lug?
Click to expand...

Inspector missed on this one.
 
It is a compliant installation. The 200A main in the sub-panel doesn't act like an over-current protection device since the SER cable (I'm assuming that is what you used) is protected by a 100A breaker in the main breaker panel. The sub-panel main breaker acts like a molded case switch in this case. You have to make sure your neutrals float and your grounds are on a separate ground bar and bonded to the sub-panel enclosure.
 
Thanks for your answers. Is there any section of the code that specifically covers this situation?

Maybe a disconnect for a sub panel? Using a breaker as a disconnect? It's seems so obvious to me but it's hard to prove a negative.
 
goldstar said:
It is a compliant installation. The 200A main in the sub-panel doesn't act like an over-current protection device since the SER cable (I'm assuming that is what you used) is protected by a 100A breaker in the main breaker panel. The sub-panel main breaker acts like a molded case switch in this case. You have to make sure your neutrals float and your grounds are on a separate ground bar and bonded to the sub-panel enclosure.
Click to expand...
I have used SER cable and it's protected by 100 amp breaker. Neutral are floating and grounds are separate bonded to panel.
 
Looking at it from the average home owner. It seems a bit deceiving to me. Probably the inspector , too. Ask him if you print up a label indicating that it's fed by a 100 amp breaker. Would that suffice?
Kind of like labeling a three prong outlet (No equipment ground Gfci Protected)
 
Patoneil said:
Thanks for your answers. Is there any section of the code that specifically covers this situation?

Maybe a disconnect for a sub panel? Using a breaker as a disconnect? It's seems so obvious to me but it's hard to prove a negative.
Click to expand...
Yes it is hard to prove such things. He is the one that has to tell you what the code violation is. Maybe show him 408.36 and tell him the panelboard is protected at or below its rating.
 
Patoneil said:
Thanks for your answers. Is there any section of the code that specifically covers this situation?

Maybe a disconnect for a sub panel? Using a breaker as a disconnect? It's seems so obvious to me but it's hard to prove a negative.
Click to expand...

There is no code section. There is nothing for you to prove, the inspector is wrong and that's why he cannot provide a code section that you have violated. Converting the panel to a MLO is not the answer when your original installation is code compliant. I would go over his head if he doesn't correct his error.
 
infinity said:
How so?
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110.3 (A) 1 Conformity - That can mean normal. The 200 amp breaker is not normally used for this installation - therefore it does not conform to normal practices which can lead to 110.12

BTW - I have done what the OP has described when material was short due to the hurricane. But I have also took the main breaker out used lugs and I have put a 100 amp breakers in them with a main clip to safely hold in in place.
 
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