# 2-meter 100 amp service



## rlc3854

Unfortunately not you. As you stated yourself that a 100 amp service is required per house (dwelling). I don't know the NEC article off hand but, each structure can only have one service unless special permission has been approved. So one service point to the structure/multiple meters (one for each dwelling/residence with a minimum 100 amp service to each.


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## MDShunk

rlc3854 said:


> Unfortunately not you. As you stated yourself that a 100 amp service is required per house (dwelling). I don't know the NEC article off hand but, each structure can only have one service unless special permission has been approved. So one service point to the structure/multiple meters (one for each dwelling/residence with a minimum 100 amp service to each.


Not true. I do apartment buildings all the time, often with a 6 or 8 hundred amp service, but only 30 amp tenant breakers.


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## Buck Parrish

Sparky, Are you saying that you have 2 two pole breakers on each side, with no main.
Because this sounds okay as long as the service is sized correctly. And you have six or less grouped.


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## Mike Guile

*$$*

Uh oh. You might have to do a redo.


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## Dennis Alwon

Technically I would say you are correct if the disconnect is rated 100 amps. Article 230.79(C) states this clear but I would imagine most inspectors will not see it that way.



> 230.79 Rating of Service Disconnecting Means.
> The service disconnecting means shall have a rating not less than the calculated load to be carried, determined in accordance with Part III, IV, or V of Article 220, as applicable. In no case shall the rating be lower than specified in 230.79(A), (B), (C), or (D).
> (C) One-Family Dwellings. *For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire*.



This does not say the se conductors must be rated 100 amps.


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## Mike Guile

*yep*

there both right, but, I think since it's two address's that's causing the need for 2x100's. The one address and apt's are just based of calculated load from what little I know. I thought I saw somewhere that a single family residence needs a min of 60 amps?? Is it 60 or 100 ?? Code Ref?


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## Dennis Alwon

Mike Guile said:


> there both right, but, I think since it's two address's that's causing the need for 2x100's. The one address and apt's are just based of calculated load from what little I know. I thought I saw somewhere that a single family residence needs a min of 60 amps?? Is it 60 or 100 ?? Code Ref?


Read my post above yours. 230.79


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## 480sparky

mike guile said:


> there both right, but, i think since it's two address's that's causing the need for 2x100's. The one address and apt's are just based of calculated load from what little i know. I thought i saw somewhere that a single family residence needs a min of 60 amps?? Is it 60 or 100 ?? Code ref?


 
100. 230.79(c).


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## MDShunk

Whether the building has one address or two, a duplex is a two family dwelling. The building code makes that clear. The 100 amp minimum for a single family dwelling does not apply.

IF, these are two seperate structures, fed off a remote meter setup someplace on the lot, then you have a problem. If it's not a duplex, but two seperate and freestanding dwellings, you need 100 amp to each.


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## 480sparky

MDShunk said:


> ........The 100 amp minimum for a single family dwelling does not apply.


 
?????

*230.79(C) One-Family Dwellings.* For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire.


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## rlc3854

MDShunk said:


> Not true. I do apartment buildings all the time, often with a 6 or 8 hundred amp service, but only 30 amp tenant breakers.


 
So are you saying that a new modern apartment can be supplied with only a 30 amp service? This is a unit that HVAC, cooking and washing appliances and water heater? How small are the units?


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## MDShunk

480sparky said:


> ?????
> 
> *230.79(C) One-Family Dwellings.* For a one-family dwelling, the service disconnecting means shall have a rating of not less than 100 amperes, 3-wire.


He described it as a duplex, with one service. A duplex is a Two-Family Dwelling.


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## MDShunk

rlc3854 said:


> So are you saying that a new modern apartment can be supplied with only a 30 amp service?


Can't recall having ever said such a thing.


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## user4818

I agree with Marc. 100 amp per unit not required in this scenario.


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## SparkYZ

Here's a picture http://yfrog.com/0velectricservicej
It's a two meter panel, rated for 100 amps. It's one service and one service drop for the two homes, and this in itself is allowed by Los Angeles and the POCO. Load calcs for square footage, appliances, etc come out to 41 amps and 50 amps for the two houses. They are separate houses. Each meter feeds a 50 and 60 amp two pole breaker, respectively. And you are allowed to rate for 125% for the service. There is no 100A main, as this would kill both meters(and houses)

Article 230.80 states " Where the service disconnecting means consist of more than one switch or circuit breaker, as permitted by 230.71, the combined ratings of all the switches used shall not be less than the rating required in 230.79" That's what we are arguing with. 

It's only one service, and yes the service is 100 amp.


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## SparkYZ

MDShunk said:


> Whether the building has one address or two, a duplex is a two family dwelling. The building code makes that clear. The 100 amp minimum for a single family dwelling does not apply.
> 
> IF, these are two seperate structures, fed off a remote meter setup someplace on the lot, then you have a problem. If it's not a duplex, but two seperate and freestanding dwellings, you need 100 amp to each.


The two meter panel is on one of the houses. The POCO and Building inspectors allowed this.


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## MDShunk

Okay, now you're contracdicting yourself. Is this a duplex or two seperate single-family dwellings?

If this is two single family dwellings, and not a duplex (2-family dwelling), then you absolutely need 100 amp to each dwelling.

I see in your added post that you put the service on one house, and that there is a seperate house also. This is two, single family dwellings. You need 100 amp to each; no way around it. This is not a duplex, as you described it earlier.


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## rlc3854

SparkYZ said:


> *The two meter panel is on one of the houses*. The POCO and Building inspectors allowed this.


So is it one structure seperated by a common wall (fire) as a duplex? Or is it two seperate structures such as a detacted garage converted to a dwelling?


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## 480sparky

MDShunk said:


> He described it as a duplex, with one service. A duplex is a Two-Family Dwelling.


And you were making reference to a SFD.


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## MDShunk

480sparky said:


> And you were making reference to a SFD.


You bet. The 100 amp minimum for a single family dwelling does not apply to a two-family dwelling.

As it turns out, we're not dealing with a 2-family dwelling in this thread, after all. It's two, single family dwellings, so it seems.


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## SparkYZ

One large lot. Two separate houses. One service drop going to an enclosure with two meters and a breaker off each meter. City has allowed us to use the two meter panel, mounted on one house, as a service drop going to the second house would not have the necessary height requirements. 
Sorry for the clarity issues guys.


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## MDShunk

SparkYZ said:


> One large lot. Two separate houses. One service drop going to an enclosure with two meters and a breaker off each meter. City has allowed this ONE SERVICE ENCLOSURE.
> 
> Sorry for the clarity issues guys.


Exactly where you mounted your metering and service equipment really has no bearing on the issue at hand. You could have mounted it 10 blocks away, and it wouldn't matter. You have two, single-family dwellings. You need 100 amp to each. The only way around this might be to mount the houses on wheels and call them park trailers.


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## SparkYZ

MDShunk said:


> Exactly where you mounted your metering and service equipment really has no bearing on the issue at hand. You could have mounted it 10 blocks away, and it wouldn't matter. You have two, single-family dwellings. You need 100 amp to each. The only way around this might be to mount the houses on wheels and call them park trailers.


So 230.80 has no bearing on this? 

I'm well aware that a residential service needs to be 100A. I just wasnt sure if this is a standard situation. 

Well if we get hosed, atleast only one subpanel is done, and its 6'' away from the service. The conduit going to the second house isnt completed, so we're not too screwed. 

Thanks for the input guys, I promise I'm not a hack! 


Cant I just run some 2/0 free air and use a carlon pvc weatherhead and skotchkote the crap out of it???? :jester:


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## LGLS

4 characters...


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## SparkYZ

LawnGuyLandSparky said:


> 100 main St. Apt 1 and Apt 2 are also 2 different addresses. Doesn't mean Apt's 1 & 2 both need 100a services...
> 
> Same lot, same building, ONE C of O, One address (irrelevant) one 100a service.


Apartments are different I believe. These are two single family dwellings


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## LGLS

SparkYZ said:


> Apartments are different I believe. These are two single family dwellings


Each has a different C of O? 

I'm shocked.... SHOCKED that any city would allow 2 separate single family homes to share one service on one house.

Shocked I tell you...


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## SparkYZ

LawnGuyLandSparky said:


> Each has a different C of O?
> 
> I'm shocked.... SHOCKED that any city would allow 2 separate single family homes to share one service on one house.
> 
> Shocked I tell you...


What is a C of O? This whole neighborhood is set up this way too


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## JayH

SparkYZ said:


> So 230.80 has no bearing on this?
> 
> I'm well aware that a residential service needs to be 100A. I just wasnt sure if this is a standard situation.
> 
> Well if we get hosed, atleast only one subpanel is done, and its 6'' away from the service. The conduit going to the second house isnt completed, so we're not too screwed.
> 
> Thanks for the input guys, I promise I'm not a hack!
> 
> 
> Cant I just run some 2/0 free air and use a carlon pvc weatherhead and skotchkote the crap out of it???? :jester:


When I worked in LA County (over 10 years ago) service risers were required to be 1 1/4" GRC.

The AHJ should have a handout for service requirements.


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## 480sparky

SparkYZ said:


> What is a C of O? This whole neighborhood is set up this way too


 
Certificate of Occupancy.

Legal permission to use the structure for the purpose intended. Usually issued after all final inspections.


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## Dennis Alwon

You want to play games? Take the 100 amp breaker that is suppose to feed the remote building and add a small 100 amp panel next to it. Put a 60 amp breaker in there and feed the house. BS? yes, but technically not a code violation since you are only required to have a 100 amp disconnect. That is provided in the main service panel.

Personally I would not mess with this and would install 100 amp wiring to the other structure, which, I believe, is the intent of the code.


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## Mike Guile

*Duplex*

Around here the AHJ would make a duplex be 2x100 amp services and 2 meters since it is 2 address's (no apt. numbers) and only one structure. They would list that resi. If it was one address with apt. numbers and a triplex then you could do load calcs, demand factors and potentially 1x100 amp service for all. If it was quad with apt. numbers then commercial and definately load calc determines service. 

I don't think they let us do load calc's with demands if they were separate address's from memory around here.


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## jgarnett

SparkYZ said:


> Here's a picture http://yfrog.com/0velectricservicej
> It's a two meter panel, rated for 100 amps. It's one service and one service drop for the two homes, and this in itself is allowed by Los Angeles and the POCO. Load calcs for square footage, appliances, etc come out to 41 amps and 50 amps for the two houses. They are separate houses. Each meter feeds a 50 and 60 amp two pole breaker, respectively. And you are allowed to rate for 125% for the service. There is no 100A main, as this would kill both meters(and houses)
> 
> Article 230.80 states " Where the service disconnecting means consist of more than one switch or circuit breaker, as permitted by 230.71, the combined ratings of all the switches used shall not be less than the rating required in 230.79" That's what we are arguing with.
> 
> It's only one service, and yes the service is 100 amp.


Code States if you feed a sub panel with more than two circuits, it must be with a min. of 60 amps, how are you geting by with a two pole 50 ?


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## Bob Badger

jgarnett said:


> Code States if you feed a sub panel with more than two circuits, it must be with a min. of 60 amps, how are you geting by with a two pole 50 ?


Can you tell me where the code says that?


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## VersaJoe

Bob Badger said:


> Can you tell me where the code says that?


I would like to know as well! :blink:


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## rlc3854

MDShunk said:


> Not true. I do apartment buildings all the time, often with a 6 or 8 hundred amp service, but only 30 amp tenant breakers.





MDShunk said:


> Can't recall having ever said such a thing.


 
Marc, can you explain how you can get the 30 amp tenant breaker by the AHJ? Is it because the buildings have central plants for processing HVAC/water etc?


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## MDShunk

rlc3854 said:


> Marc, can you explain how you can get the 30 amp tenant breaker by the AHJ?


They generally ask to see a load calculation worksheet.


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## SparkYZ

The scotchkote thing was a joke. The riser is 2" rigid


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## jgarnett

bob badger said:


> can you tell me where the code says that?


 
230.79 a,b,c, (d)


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## Dennis Alwon

jgarnett said:


> 230.79 a,b,c, (d)


Not quite. article 230 is for services. Look at 225.39(B)-- you did say sub panel


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## jgarnett

Dennis Alwon said:


> Not quite. article 230 is for services. Look at 225.39(B)-- you did say sub panel


 
Same differecce 225.39(b) Outside Branch circuits and feeders 
is correct, Ithought the disconnect was in the meter center, that would have fell into 230.79, what ever way you want to look at it, still need a two pole 60


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## Shockdoc

SparkYZ said:


> Hey guys, we're arguing with an inspector on a duplex house we're doing.
> This job is two 700SF houses on one lot, two addresses. Now, I know every residential service needs to be 100A, no less, but there is an exception ( i cant remember the art number, that states if two or more service disconnects are in one enclosure, then they can be less than 100A.
> With the load calculations, each house needs no more than 50A and 60A, respectively.
> 
> So we have one two-meter 100A service enclosure, with a 50A 2P and a 60A 2P feeding subpanels on each dwelling. Inspector is calling for 100A on each house, even though each house does not have a service.
> 
> I'm interpretting the code as a SERVICE (of which there is only one on the lot) needs 100A. It has it. But each dwelling is fed off of a 50 or 60.
> 
> Who's right?


As far as i see it, as long as you have a w/p main panel with a 100 amp m/b feeding your 60 amp c/b to your sub feed you are legit. I recently performed this as a service division and it did pass inspection.you will need a four ckt 100a w/p panel, do not forget to secure the main breaker to the panel.


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