HWCostruction

Will the NEC allow 2-200 amp service panels to be wired from the same meter base in a residence? Thanks in advance for your responses.

JohnJ0906

Yes. A very common instalation around here.

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John from Baltimore
"One Day at a Time"
All replies based on the 2008 NEC

vocivictim

Yes, as long as the calculated load doesn't exceed the allowable ampacity of the service entrance conductors. You can actually have as many as six panels.

Kgmz

Yes, have this setup at one of my homes.

Celtic

I think a bit more information is needed...but in general, yes.

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TrblShooter

Wouldn't that require a 400 amp rated meter can, double barrel lugs and 400 amp rated service entrance conductors as well?
Maybe I am just assuming he means off of a 200amp riser and in a 200 amp can...*shrug
Or is that the missing info you speak of?

Celtic

Why?
The size of the service is dictated by the loads served...not by the cumulative total of the breaker ratings.

In my own home, I have a 200A panel being fed from a 50A CB.
I'm pulling no where near the 50A that is feeding the 200A panel - but I needed more than 8/12 spaces.



I agree...w/o some more input from the OP it's anyone guess what he has/wants to do/is talking about.

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Jason W

Thats what I did at my place. I took 200 to the house and will take the other 200 to a future shop. Glad I did it 5 years ago when we got the place.

My hope is that it will avoid brown outs in the house when I run equipment in the shop but I don't know if thats actually the way it works. On the plus side, I can pay residential rates for the service

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Vermont Historic Preservation Group

Speedy Petey

Yes, sort of.
This is typically a 320/400 meter pan. 320A continuous, which is what the service entrance conductors are sized for.

VERY typical installation.

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TrblShooter

Umm the size of the over current protection (circuit breaker) most certainly dictates the min size of the conductors allowed...you have a 200 amp "rated" panel being fed by a 50amp breaker, which makes it nothing more then a big 50 amp panel.
He asked if can he feed 2-200 amp panels from the same meter can. I'm just saying if it did, he would need a 400 (320) rated meter and service entrance cables.
If he asked if he could run two 200amp "rated" panels with 50amp main breakers in them (like yours), then of course he could provided he used approved lugs to do so. (In the meter) Good luck getting 200amp rated wire under any 50 amp breaker BTW lol
The reason I asked, is because no he cannot run 2-200 amp panels off of 1 - 200amp service entrance feed (if both panels have a 200amp main breaker) that could possibly overload the service entrance wiring which would only be rated at 200 amps.
Electricians are required to do load calcs to figure out what size service they require. If they decide to install a larger service, thats fine, but they are then required to meet all the proper installation methods of that size service.
You can't just decide halfway through that you are only going to use this much of it..so it doesnt matter. UNLESS you decided to install 400(320) amp service wiring and meter and then only install 200amp panel, but you cant do it the other way.

Yup Speedy I know what you are saying, but I just read it as, can he put two 200 panels on 1 200 amp service. Which the answer would be, no.
The way you mentioned is exactly how it should be done
HWC didn't say what size meter base so I just assumed he meant a 200amp one.
If it is a 200amp meter base then no you cannot put 2-200amp panels (with 200 amp main breakers on it)
If it is a 400amp meter base, then yes you can.

Celtic

To some degree.
There is more to it than what you are saying.


That is correct.
...and the OP is simply asking:
To which, the answer is yes....maybe what he needs is just 84 poles @ 200A

That is incorrect....you even detailed it above.


If the calculated load is below the max. wire size for [say] a 50A CB, why would you run #4/0?

Sorry, but you answer does not pass the test.
I can most certainly run 2 200A panels off a 50A, 100A or even a 200A MCB....as long as my calc. load is under 200A.

Have you ever performed a load. calc?


????
"As you read it"?
More likely as you infer it.
The OP asked SIMPLY:
Will the NEC allow 2-200 amp service panels to be wired from the same meter base in a residence?

The answer is YES.
I don't see how it can be read any other way.

You can infer that he wants 400A of available ampacity - but that is not what was asked.
We have NO IDEA of what the OP is planning this for...and as I said previously:
Considering we are clueless to the OP's intention, the only answer is YES.



That is ASSUMING the OP requires that amount of ampacity.
However, that is NOT what the OP asked.


You are wrong TS.
Sorry to have to tell you this.

On a 200A meter pan, I can put as many 200A panels as I want - as long as my calculated load does not exceed 200A.
Period.
On a 400A meter pan, I can put as many 200A panels as I want - as long as my calculated load does not exceed 400A.
Period.


Now we can debate the issue of landing 2 sets of 4/0's in a single 200A meter base and see where that leads if you want.

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mdshunk

I have put way more than 2, 200 amp panels on a 200 amp service when automation was involved. Lots and lots of dedicated circuits that don't draw but a trickle.

Celtic

Say it ain't so!

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TrblShooter

Boy was I way off..reading about it now and speaking to a friend.
Crazy how you can be taught one thing and later when ya start to start out on your own, come to find it wasn't even close lol
I am coming to the conclusion I was taught they way someone wanted it done, not the way it could be....
My deepest apologies and thanks for the lesson

Celtic

Stick around TS...no need for apologies....I've been doing it wrong for about 15 years...within the past 5 yrs or so I started to get a clue ....seriously.

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TrblShooter

lol Oh I Plan to stick around Celtic...heck this one topic could have cost me tons lol
I'm definitely looking to get a clue, now more then ever!
Thanks again

Celtic

You're learning already!

Give it a few hundred posts and you'll be all crabby like the rest of us

BTW, I am a licensed EC in NJ....the pie is my side work

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dr electro

Need a 400 amp meter base and must run ground wires (400amp, #2 cu) from each panel to water main or 1 400 amp ground wire from meter base to water main, also a ground from meter base to ground rod, think that can still be a #6, don't have my book handy, someone else knows, I'm sure.
My region now requires 2 ground rods, 6 feet apart. Good thing I have a good driver.

Speedy Petey

This would require a #4cu from each 200A panel to the water main.


Most areas no longer require/want a grounding electrode connection inside a meter base. This location is not considered "accessible" since it is locked and illegal to break the seal.



Most areas do.

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thom

We needed a true 600A residential service a few years back. The PoCo didn't have triplex large enough for 600A and would not split apart a quad plex. We ended up with 2 @ 300A meter bases and panels. Because of the prohibition of two services to one building rule, we were required to install them side by side with large engraved labels explaining the installation. The service drawings required an engineers stamp as did all the load calcs. That was a quick $250 for the engineer. I did the calcs and drawings, took them to his office with a check and he spent 15 minutes verifying my calcs.