# using 200 amp mb subpanel with 100 amp service



## Hippie (May 12, 2011)

Last week I installed a 100 amp service on a very tiny 2 room pre built "eco cottage." Meter and main breaker on outside wall, panel about 10 ft away inside. 

Plan called for 100 amp service, when the building was delivered it had a 200a MB panel installed. This morning I get an email from the builder saying the inspector said you "can't put 100 amp wire on a 200 amp service." Seriously? Is he wrong here or am I missing something? I have never heard of this being a problem, the wire to the panel is protected at the disconnect outside, not by the 200a breaker in the panel


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## McClary’s Electrical (Feb 21, 2009)

If there is a 100 amp disconnect outside then he is wrong


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## Pete m. (Nov 19, 2011)

As long as the lugs on the 200 amp breaker are listed for use with the wire size you have I agree with McClary.

Pete


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## nolabama (Oct 3, 2007)

Inspector is wrziisong


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## chicken steve (Mar 22, 2011)

if the OCPD is 100amps, it doesn't matter if it's a 1000amp panel

to add, i've sold more 200amp services because prefabs come with them than dones has pills

this by no means is dishonest, i inform all my customers a demand load calc is available, even on-line, go plug in the #'s yourself

~CS~


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## Hippie (May 12, 2011)

mcclary's electrical said:


> If there is a 100 amp disconnect outside then he is wrong


There is. This is my first time dealing with this guy, so I don't really know anything about him other than that his name is one of the clans that's big in the rinky Dink small town local govt bullsh!t around here. 

There is no 200 amp service, the permit was for a 100 and that's what I installed.


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## Hippie (May 12, 2011)

chicken steve said:


> if the OCPD is 100amps, it doesn't matter if it's a 1000amp panel
> 
> to add, i've sold more 200amp services because prefabs come with them than dones has pills
> 
> ...


This one is so tiny there would really be no reason for it. The only real loads are a small mini split and water heater, its not even 300sq ft


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## chicken steve (Mar 22, 2011)

yeah, but the owners might call the manufacturers tech support Hippee

Apex out of Penn(iirc) is one such co. btw, they may as well have a goat asnwer the phone im(not so)ho....

then what?

110.3(B) bias does exist....

~CS~


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## Hippie (May 12, 2011)

chicken steve said:


> yeah, but the owners might call the manufacturers tech support Hippee
> 
> Apex out of Penn(iirc) is one such co. btw, they may as well have a goat asnwer the phone im(not so)ho....
> 
> ...


Then ill show them this


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## sbrn33 (Mar 15, 2007)

What if the pre-fab is listed for a 200 ampere service. If I was an inspector (god help some of the people around here) and this building came with a 200. I might ask why????
I know OCP wise he is fine but what about load calc's.


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## McClary’s Electrical (Feb 21, 2009)

sbrn33 said:


> What if the pre-fab is listed for a 200 ampere service. If I was an inspector (god help some of the people around here) and this building came with a 200. I might ask why????
> I know OCP wise he is fine but what about load calc's.


If he was ok with a 100 then a 200 ia certainly fine.


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## sbrn33 (Mar 15, 2007)

That's what I am saying. He might not be OK with a 100. The pre-fab might require a 200.


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## Hippie (May 12, 2011)

sbrn33 said:


> That's what I am saying. He might not be OK with a 100. The pre-fab might require a 200.


Drawing says 100 amp, I posted a pic of it on the first page


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## sbrn33 (Mar 15, 2007)

The drawing and what actually shows up are two different things. Have you done a load calculation ? It might take 5 minutes. If it's under 100, by all means go for it.


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## Hippie (May 12, 2011)

I just got off the phone with him, he hemmed and hawwed and couldn't answer any of my questions. I even asked him if the problem was that the lugs on the breaker were not rated for #2 wire and he said no. His issue was that "he had never seen it before" and that feeders were "always sized for the rating of the panel." He's supposed to be calling me back with the code reference :-\


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## Hippie (May 12, 2011)

sbrn33 said:


> The drawing and what actually shows up are two different things. Have you done a load calculation ? It might take 5 minutes. If it's under 100, by all means go for it.


Load calc came out to 51 amps


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## sbrn33 (Mar 15, 2007)

Just let him know that 200 is the max rating of the panel. You can feed it at any amperage as long as the wire is protected which it sounds like it is.


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## papa (Sep 15, 2011)

Remove the 200 amp main and back feed a 100 amp breaker,if insp. wont budge.


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## Hippie (May 12, 2011)

papa said:


> Remove the 200 amp main and back feed a 100 amp breaker,if insp. wont budge.


There's already a 100 a breaker outside. He wants me to remove the breaker and put lugs, which is unnecessary time and cost and I would also have to find a blank for the main


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## Dennis Alwon (May 9, 2009)

Hippie said:


> There's already a 100 a breaker outside. He wants me to remove the breaker and put lugs, which is unnecessary time and cost and I would also have to find a blank for the main


Did you tell him what you told us? The 200 amp breaker is your lugs and that is all it is there for in this purpose. Also send him a link to this thread.


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## Hippie (May 12, 2011)

Dennis Alwon said:


> Did you tell him what you told us? The 200 amp breaker is your lugs and that is all it is there for in this purpose. Also send him a link to this thread.


I did, he just kept saying he would look it up and call me back like he wanted to get off the phone. Also I just realized that taking out the main would make my wires too short


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## donselec (May 7, 2011)

its upside down...... why??:blink:


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## donselec (May 7, 2011)

really, i would have thrown that panel in the truck and installed a 20ckt...100a
as long as customer didnt pay for a 200. then he would have got the 200...


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## Hippie (May 12, 2011)

donselec said:


> really, i would have thrown that panel in the truck and installed a 20ckt...100a
> as long as customer didnt pay for a 200. then he would have got the 200...


The panel came that way already installed upside down and all, all I did was the service and feeder to the panel


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## B4T (Feb 10, 2009)

donselec said:


> its upside down...... why??:blink:


The feed is from the bottom and there isn't any up or down with panels.. 

It would not make any sense to flip the panel and run an extra 36" of cable..


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## nolabama (Oct 3, 2007)

I am glad I don't deal with inspectors.


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## Pete m. (Nov 19, 2011)

nolabama said:


> I am glad I don't deal with inspectors.


What the heck did I ever do to you?

Pete


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## kbsparky (Sep 20, 2007)

donselec said:


> its upside down...... why??:blink:


Bite your tongue, and get educated! It is NOT upside down, it IS set for bottom feed!!!

I hate it when modular units come with pre-wired panels that have the mains at the TOP, with the main conduit for feeding it at the BOTTOM! 

It is correct orientation in this instance.


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## Bbsound (Dec 16, 2011)

donselec said:


> its upside down...... why??:blink:


no, it is not!!!


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## kbsparky (Sep 20, 2007)

nolabama said:


> I am glad I don't deal with inspectors.


I don't mind dealing with inspectors. It's the ignorant ones that I don't like dealing with .... as well as the nit-picky ones!


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## Bbsound (Dec 16, 2011)

mcclary's electrical said:


> If there is a 100 amp FUSED disconnect outside then he is wrong


Let me fix that for ya':thumbsup:


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## manchestersparky (Mar 25, 2007)

Hippie said:


> Last week I installed a 100 amp service on a very tiny 2 room pre built "eco cottage." Meter and main breaker on outside wall, panel about 10 ft away inside.
> 
> Plan called for 100 amp service, when the building was delivered it had a 200a MB panel installed. This morning I get an email from the builder saying the inspector said you "can't put 100 amp wire on a 200 amp service." Seriously? Is he wrong here or am I missing something? I have never heard of this being a problem, the wire to the panel is protected at the disconnect outside, not by the 200a breaker in the panel



My rely would have been: I* did not* use 100 amp wire on a 200 amp service. I *did use 100 amp wire on a 100 amp feeder.*
Then explain that the service is the service rated disconnect on the exterior of the structure.


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## McClary’s Electrical (Feb 21, 2009)

I would also like to add that if this is a factory assembled cottage, the inspector has no business even walking through the front door. His inspection stops at the service. (you might have to explaain to him the definition of a service)


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## 347sparky (May 14, 2012)

Tell him not a 200A breaker but a 200A disconnect.


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## kbsparky (Sep 20, 2007)

mcclary's electrical said:


> I would also like to add that if this is a factory assembled cottage, the inspector has no business even walking through the front door. His inspection stops at the service. (you might have to explaain to him the definition of a service)


This only applies to HUD certified units.


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## McClary’s Electrical (Feb 21, 2009)

kbsparky said:


> This only applies to HUD certified units.


 
No, mobile homes too.


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## McClary’s Electrical (Feb 21, 2009)

I think it's a typo on the drawing anyway. 2" pvc and #4 GEC tells me it's a 200


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## kbsparky (Sep 20, 2007)

mcclary's electrical said:


> No, mobile homes too.


You are arguing and agreeing with me at the same time. 

Mobile homes have to be HUD certified to be exempt from local-yocal codes and inspectors...:whistling2:


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## Hippie (May 12, 2011)

manchestersparky said:


> My rely would have been: I did not use 100 amp wire on a 200 amp service. I did use 100 amp wire on a 100 amp feeder.
> Then explain that the service is the service rated disconnect on the exterior of the structure.


That is exactly what I told him


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## Hippie (May 12, 2011)

mcclary's electrical said:


> I think it's a typo on the drawing anyway. 2" pvc and #4 GEC tells me it's a 200


Yeah it turns out it was, but this thing is the size of a shed, 100 is quite sufficient for what's there. The factory said it was a mistake and that they would pay to replace it if need be, but that is really irrelevant to the original issue, which is that there is nothing wrong with a 200 amp panel on a 100 amp feeder.


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## Hippie (May 12, 2011)

Never heard back from the inspector but had a green sticker yesterday morning lol


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