Max number service disconnects

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Ragin Cajun

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Upstate S.C.
The attached figure from Mike Holt's book shows a building (apartment complex?) with two services, one on each side. This gives a total of 2 x 6 = 12 meters.

What does your local AHJ have to say about this?

I have been told that for an apartment complex, to do this there must be a 2 hour fire wall effectively separating the building into two "buildings."

Am I wrong here? Have I been "led astray?"

THANKS!
 
Ragin Cajun said:
What does your local AHJ have to say about this?
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Around here, it's a common installation. Anything from a 24-plex to a duplex may have services on opposite sides of the building.

I have been told that for an apartment complex, to do this there must be a 2 hour fire wall effectively separating the building into two "buildings."
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That essentially splits the building into two structures sharing a common wall, yes. I think that standard is according to the building code, but I'm not for certain.

After splitting with a fire wall, there are two structures with a service apiece, essentially.
 
230.71(A) ?General. . The service disconnecting means for each service ?.. shall consist of not more than six ?..?

230.2 ?Number of Services. . A building or other structure served shall be supplied by only one service unless permitted in 230.2(A) through (D).?

230.2(B)(1) ?Multiple-occupancy buildings where there is no available space for service equipment accessible to all occupanants?

One service is limited to six disconnects, but multiple occupancy is not limited to one service. . So counting meters on a multiple occupancy building, to see if you have more than 6, is comparing apples to oranges.

A single ?strip store? building could have 20 or more stores, side by side in one building and have just as many service drops, meters, and mains.

As far as where the fire walls are required, the existence of a fire wall is a function of the building code, not the electrical code. . The NEC doesn?t require fire walls to define multiple occupancy. . You have to look to the building code [local or state] to determine how to build a particular multiple occupancy building. . Whatever firewall requirements you find or don?t find there, it?s still a multiple occupancy building and 230.2(B)(1) is still valid.

David
 
Remember that according to the NEC, a meter is not a service. The general rule is that a "building" may only have one electrical service, but there are many exceptions that allow additional services. Also remember that the disconnect does not have to be installed until the serice entance cable enters the building and that each "disconnect" may consist of up to six devices. This can get very confusing in a large multfamily dwelling or other multiple occupancy building. There is one apartment building in this area that has SEC cable running all over the back of the building because the service disconnects are located in each occupancy. The building looks like it is being attacked by a giant octopus! But it meets code!
 
dnem,

230.2(B) Special Occupancies. By special permission,additional services------

------. Multi-occupancy buildings under this code need Special Permission.

Please include all of the information as to not mislead people.

Thank you,
 
Jim W in Tampa said:
If it can be classified as 2 buildings then your back to the 6 disconnect rule.I dont like it but that how it reads.
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Even if benaround won't give you the special permission you need for multiple service drops, he still might give permission for individual mains. . The engineer or architect doesn?t have to provide a main disconnect for the entire structure. . The single service drop can terminate in a trough that can house taps to individual mains for each tenant. . And each tenant can have as many as 6 main disconnects. . So the number 6 as a maximum then applies to each tenant individually.

David

P.S. benaround, don't get upset, my choice of wording is just joking around.
 
dnem said:
Even if benaround won't give you the special permission you need for multiple service drops, he still might give permission for individual mains. . The engineer or architect doesn?t have to provide a main disconnect for the entire structure. . The single service drop can terminate in a trough that can house taps to individual mains for each tenant. . And each tenant can have as many as 6 main disconnects. . So the number 6 as a maximum then applies to each tenant individually.

David
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David (or anyone). You can tap as long as all your service wires remain outside. Once inside you must terminate in on a disconnect correct?
 
Each apartment or condo can have 1 to 6 disconnects.
230.71(A) General The service disconnecting means for each service permitted by 230.2, or for each set of service-entrance conductors permitted by 230.40, Exception Nos. 1, 3, 4, or 5, shall consist of not more than six switches or sets of circuit breakers, ...
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Don
 
I believe Dave has posted an answer that is well written for the question posted. As much as some of us may disagree with the principal of safety with this type of arrangement, it is permitted.

Also, I would definitely check for local amendments and with the Utility company for specific local requirements, as Jim has mentioned.
 
The NEC has a provision that a building shall be supplied by only one service.
and the definition of the "building" in the NEC, to wit:

"A structure that stands alone or that is cut off from adjoining structures by fire walls with all openinings therein protected by approved fire doors."

Assuming that there is a building with two-occupancy and separated by an approved fire wall. This two occupancy are considered as an individual building with reference to the definition of the "building" in the NEC. With these, each occupancy can be served by an individual service, lets say service drop for overhead service. There is no need for a special permission because each occupancy is considered as an individual building by the presence of ire wall. You can now have maximum of six service disconnects for each service...

mikeholt drawings was just a representation that if two service drop are allowed/permitted to served a building, then each service drop can have a maximum of six service disconnects..
 
enteng14 said:
The NEC has a provision that a building shall be supplied by only one service.
and the definition of the "building" in the NEC, ...
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The NEC also allows multiple services to one building under certain circumstances.

230.2(A)

230.2(B)

230.2(C)

230.2(D)

All give allowances for more than one service to one building.

Now a a group of building separated by firewalls is another story all together.

More than one building can obviously receive more than one service.

I know this so I had to take action. :)
 
iwire said:
The NEC also allows multiple services to one building under certain circumstances.

230.2(A)

230.2(B)

230.2(C)

230.2(D)

All give allowances for more than one service to one building.

Now a a group of building separated by firewalls is another story all together.

More than one building can obviously receive more than one service.

I know this so I had to take action. :)
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These are special conditions/occupancies of the code sir and in order to have a multiple service it must be approved by the AHJ prior to energization. please correct me if i'm wrong. I believe that i could learn a lot on this forum because of the expertise, experience and knowledge of individual.. Thank you
 
enteng14 said:
These are special conditions/occupancies of the code sir and in order to have a multiple service it must be approved by the AHJ prior to energization.
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No, not for most of those sections I quoted.

Only the provisions in 230.2(B) require special permission

230.2(A), 230.2(C), 230.2(D) do not require special permission although special permission may be given.
 
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