200 amp main breaker panel used as 100 amp sub panel

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Buck Parrish said:
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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sorry but I'm not buying it. :)
So I cannot protect a 200 amp disconnect switch with a 100 amp OCPD?
 
Buck Parrish said:
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
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I would argue that since 200A panels are so common and thus cheaper because of mass production, that it is completely normal to use a panel with a 200A main breaker in an application where a MLO panel would be perfectly servicable.

-Jon
 
One question is if there is anything about this particular installation that requires selective coordination? Only the OP can provide such details. However even if this is the case, the _inspector_ should have identified the specific requirement.

-Jon
 
winnie said:
I would argue that since 200A panels are so common and thus cheaper because of mass production, that it is completely normal to use a panel with a 200A main breaker in an application where a MLO panel would be perfectly servicable.

-Jon
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I used it because it was so cheap, less costly than a MLO panel.
 
Patoneil said:
Thanks for your answers. Is there any section of the code that specifically covers this situation?
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No. It's on the inspector to tell you which NEC article you are in violation of; it's not on you to reference every article in the code (which would be all of them) that doesn't say you can't do it.
 
Look, I'm not against it. I'm playing devils advocate on the inspectors behalf. However..., a clearly visible 200 on the Main breaker is deceiving to the average home owner.
Imagine 5 years even 20 years from now the home is owned by some one else. The 200 is on the breaker. That's why I said it should be clearly labeled 100 amps .
I would not do it to save $75.00. I take pride in my work.
 
A 200A main breaker on a sub panel fed by a 100A load breaker is merely a switch.
 
Buck Parrish said:
Look, I'm not against it. I'm playing devils advocate on the inspectors behalf. However..., a clearly visible 200 on the Main breaker is deceiving to the average home owner.
Imagine 5 years even 20 years from now the home is owned by some one else. The 200 is on the breaker. That's why I said it should be clearly labeled 100 amps .
I would not do it to save $75.00. I take pride in my work.
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Which still doesn't mean much. One could run actual 200 amp feeder to this, but that don't necessarily mean you will have 200 amp capacity out of it. If everything comes from a 200 amp service and there is already a calculated load of 100 amps on whatever else is present - you sort of only have 100 amp capacity here anyway.

If you have two 200 amp panels as your service equipment you might say you have a 400 amp service, yet you can not run an individual load of 250 amps from this setup either.
 
Buck Parrish said:
Look, I'm not against it. I'm playing devils advocate on the inspectors behalf. However..., a clearly visible 200 on the Main breaker is deceiving to the average home owner.
Imagine 5 years even 20 years from now the home is owned by some one else. The 200 is on the breaker. That's why I said it should be clearly labeled 100 amps .
I would not do it to save $75.00. I take pride in my work.
Click to expand...

The average homeowner has no idea how many amps their service is. I think the subset of DIY homeowners who are smart enough to understand the significance, dumb enough not to notice the upstream 100A, and scrupulous enough to care ... is too small to matter.
 
jaggedben said:
The average homeowner has no idea how many amps their service is. I think the subset of DIY homeowners who are smart enough to understand the significance, dumb enough not to notice the upstream 100A, and scrupulous enough to care ... is too small to matter.
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Nor do they know what it means, they just assume bigger means better.

200 amp supply is somewhat the standard anymore, but unless you have a really large house or electric heating, often a 100 amp supply is plenty for most homes. Code wants a minimum 100 amp supply but reality is some cases you could get by with even less, especially if you have gas supplying all the major heating appliances.
 
As long as the feeder wire from the main panel is sized for 100 amp breaker (#3 AWG or larger) and the minimum rating of the sub panel are 100 amps (which it is), you are good as long as the neutral and grounds are kept separate in the sub panel.

You don't even need a main breaker in the sub panel. MLO is fine as well. As you say, your 200 amp breaker in sub panel is acting more like a disconnect switch and possibly a back up for a short circuit in case the feeder breaker short circuit instantaneous system fails.

Ask the inspector what code you are violating? Better yet, get him on this forum!
 
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