Three Service Disconnects

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Dennis Alwon

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So your description of a single riser to two meters, or two separate riser would both describe two "services" as I read the code.

That's my confusion-- I guess the problem I have is with all the exceptions in 230.40 it seems like most cases would allow more than 1 service. I can't imagine many cases where you would want more than 1 meter and not have more than one occupant.
 

al hildenbrand

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Here's another way of showing the information I wrote in my posts above.

Two disconnects outside and one inside is throwing me.


642Schematicweb.jpg
 

roger

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You're welcome Al, but I don't know what I did to fix it. :)

Roger
 

david luchini

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That's my confusion-- I guess the problem I have is with all the exceptions in 230.40 it seems like most cases would allow more than 1 service.

I think only a couple of the exceptions in 230.40 would allow more than 1 service in a building.

Exception 1 talks about the multiple services allowed by 230.2.
Exception 2 would allow multiple services from a drop, but would be one service from a lateral 1/0 or larger. But the two to six disconnects must be grouped, so its basically the same result as one service with 2-6 disconnects in a common enclosure, but it 2-6 disconnects in different enclosures.
Exception 3 allows services in separate structures from the same lateral/drop. Not multiple services in one building.
Exception 4 does allow multiple services. This would seem to be the exception that applies to Al's case.
Exception 5 is for PV, firepumps, etc. Separate services, but part of the same occupancy.


I can't imagine many cases where you would want more than 1 meter and not have more than one occupant.

Except for maybe fire pump services, or where the building is large enough for more than one service. Then I could see multiple meter for one occupant.
 

david luchini

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Two disconnects outside and one inside is throwing me.

230.70(A)(1) requires that the service disconnecting means be installed at a readily accessible location either outside of a building or inside nearest the point of entrance of the service conductors.

So your outside and inside disconnects should be fine (assuming the inside one is nearest the point of entrance....)

Of course per 230.2(E), there should be identification at both locations indicating the location of the other service disconnect.
 

al hildenbrand

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Of course per 230.2(E), there should be identification at both locations indicating the location of the other service disconnect.
This is starting to make some sense, after this morning's coffee.

But, in the case of this little two family dwelling in my two photos and one sketch, there is only one service (Article 100), right? That is, there is only one Service Point at the Service Drop, at which two sets of service-entrance conductors are connected.

Seems to me that 230.2(E) wouldn't apply as there is only one service.
 
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Ruff-N

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This is starting to make some sense, after this morning's coffee.

But, in the case of this little two family dwelling in my two photos and one sketch, there is only one service (Article 100), right? That is, there is only one Service Point at the Service Drop, at which two sets of service-entrance conductors are connected.

Seems to me that 230.2(E) wouldn't apply as there is only one service.
According to NEC 2005 Art.230.40 Exc. No. 2 it is two services connected to one service drop. And then the AHJ would add NEC 2005 Art. 230.2 (B) (1). The only thing in question is the location of the first point of disconnect needs to be under or besides the house meter and then the panel in the basement becomes a sub-panel, and a whole new code art. would apply to that. JM2cW
 

david luchini

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This is starting to make some sense, after this morning's coffee.

But, in the case of this little two family dwelling in my two photos and one sketch, there is only one service (Article 100), right? That is, there is only one Service Point at the Service Drop, at which two sets of service-entrance conductors are connected.

Seems to me that 230.2(E) wouldn't apply as there is only one service.

I'm of the opinion that one service drop supplying multiple sets of service entrance conductors would constitute multiple services.

If you read the second sentence of 230.2, it describes a situation where multiple sets of service entrance conductors (1/0 or larger) supplied from one service lateral would be "considered" to be supplying one service.

I would read this as meaning other situations where multiple sets of service entrance conductors supplied from one service lateral/drop would be considered separate services.
 

al hildenbrand

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I would read this as meaning other situations where multiple sets of service entrance conductors supplied from one service lateral/drop would be considered separate services.
Interesting . . . OK, the NEC is largely positive language. Here's the second sentence of 230.2:
2008 NEC 230.2
. . . .
For the purpose of 230.40, Exception No. 2 only, underground sets of conductors, 1/0 AWG and larger, running to the same location and connected together at their supply end but not connected together at their load end shall be considered to be supplying one service.
Are you saying that, because the NEC says this one case IS one service, that assemblies that don't fit the description in the second sentence ARE NOT one service?
 

david luchini

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Interesting . . . OK, the NEC is largely positive language. Here's the second sentence of 230.2: Are you saying that, because the NEC says this one case IS one service, that assemblies that don't fit the description in the second sentence ARE NOT one service?

Yes, that is what I'm saying. Why else would they go through the trouble of telling you to "consider" that one specific example "one service" if it wouldn't be considered separate services in the first place?
 

al hildenbrand

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According to NEC 2005 . . .
This dwelling is under the 2008 NEC.
The only thing in question is the location of the first point of disconnect . . .
I agree.

This morning's clarity is leading me to see the "or for each set of service-entrance conductors" in 230.71(A) as allowing me to side step whether the two sets of service-entrance conductors connected to one service point are one or two services.

What I'm seeing, seems to me, is that the House panel could have six service disconnects in it, and the exterior two meter pack could have a total of six service disconnects.
 

david luchini

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What I'm seeing, seems to me, is that the House panel could have six service disconnects in it, and the exterior two meter pack could have a total of six service disconnects.

That's exactly how I would see it. And I'd want to see the identification required in 230.2(E), even if you didn't consider it two services, just for safety sake.
 

al hildenbrand

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Yes, that is what I'm saying.
I'm not so sure. Again, the NEC is positive language. In this case, that is, the second sentence of 230.2, an assembly of a certain type IS considered one service. Period. The implied negative, that is, all assemblies NOT of this certain type, are NOT one service is not there in positve language, therefore, the NEC is silent, in this sentence of 230.2, about all assemblies not of this certain type.
 

Ruff-N

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Interesting . . . OK, the NEC is largely positive language. Here's the second sentence of 230.2: Are you saying that, because the NEC says this one case IS one service, that assemblies that don't fit the description in the second sentence ARE NOT one service?

According to the info I read Per 230.2 Underground sets of conductors are permitted to be run to the same building or structure in accordance to the provisions of 230.40. Ex 2 the conductors must be sized at least No. 1/0 and may be connected at their supply end but not their load end. Essentially, this provision permits mutiple service laterals to be considered a single service lateral.
 

al hildenbrand

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That's exactly how I would see it. And I'd want to see the identification required in 230.2(E), even if you didn't consider it two services, just for safety sake.
I understand that that is what you would want, for safety sake, and your professional status carries that responsibility for your jobs, . . . but I'm trying to look at the NEC itself, as my inspector and I will look to it.
 

al hildenbrand

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According to the info I read Per 230.2 Underground sets of conductors are permitted to be run to the same building or structure in accordance to the provisions of 230.40. Ex 2 the conductors must be sized at least No. 1/0 and may be connected at their supply end but not their load end. Essentially, this provision permits mutiple service laterals to be considered a single service lateral.
Agreed.

I'm asking questions about the two family dwelling with a house panel and meter as shown in my photos and sketch, connected at one service point to one service drop.
 

david luchini

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I'm not so sure. Again, the NEC is positive language. In this case, that is, the second sentence of 230.2, an assembly of a certain type IS considered one service. Period. The implied negative, that is, all assemblies NOT of this certain type, are NOT one service is not there in positve language, therefore, the NEC is silent, in this sentence of 230.2, about all assemblies not of this certain type.

I understand what you are saying, but it isn't logical (to me anyway.) Basically the question is whether one service drop/lateral supplying multiple service entrance sets would be considered one service or multiple services.

Or putting it another way, does each set of service entrance conductors require its own service drop/lateral in order to be considered a separate service?

A service includes the conductors and equipment for delivering electric energy. In your example, you show one service drop but two sets of service entrance conductors and two sets of service equipment. I would say that if you have two different sets of service entrance conductors and two different sets of service equipment, then by definition, you have two different services.
 
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