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Posted By: CharlieE NFPA 2002 NEC Handbook - 11/07/04 01:25 PM
I am having trouble with Exhibits 230.8 and 230.12 in the NFPA 2002 NEC Handbook. What section permits these installations without special permission? These two exhibits in the NEC Handbook are driving me nuts. Are they permitted without special permission? If so, by what section (I have been looking at sections 230.2, 230.40 Exception No. 2, and 230.71(A))?

The conclusion I have reached (so far) is that they couldn't be used as examples of special permission if the caption or text following the picture didn't say special permission was required. Therefore, in accordance with 230.40 Exception No. 2, the service laterals are considered to be a single service lateral.

My conclusion seems squirrelly to me and I am looking for some other opinions.

This is my reasoning about 230.2(A), (C), and (D).

230.2(A) would not apply if you have apartments or a regular multi-tenant building (that is what I am assuming the drawing illustrates).

230.2(C) would not apply if all the individual service disconnecting means were the same and were fairly small (100 and 200 amperes).

230.2(D) would not apply if they were all the same rate being fed from the same transformer.

With that line of reasoning, I am back to my first conclusion. [Linked Image]

Keep in mind that service is defined as "The conductors and equipment for delivering electric energy from the serving utility to the wiring system of the premises served." In other words, 230.2 is talking about service drops or service laterals, not service equipment.

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Charlie Eldridge, Indianapolis, Utility Power Guy

[This message has been edited by CharlieE (edited 11-07-2004).]
Posted By: Creighton Re: NFPA 2002 NEC Handbook - 11/07/04 06:02 PM
Charlie: I agree with you. Both of these illustrated service conditions require special permission, in writing.
Posted By: iwire Re: NFPA 2002 NEC Handbook - 11/07/04 06:34 PM
Creighton why would I need written permission if the reason for doing this falls under one of the following?


230.2(C)(1) or (2)


Once we have more than one service we must be able to have more than six disconnects.

I am just asking as I have been following Charlie's question on another forum and for the life of me I am missing the problem. [Linked Image]

Posted By: Creighton Re: NFPA 2002 NEC Handbook - 11/08/04 07:04 PM

I suggest you review Chcarlie's comments.

230.2(A) obviously does not apply.

(C) (1) and (2) could apply if the loads are high, but if so the legend under the Exhibits should so state.

(D) could also apply if there were indeed different characteristics of supply, but if so the legends shouldl so state.

The applicable requirement is (C)(3), "by special permission" which means in writing.

Posted By: e57 Re: NFPA 2002 NEC Handbook - 11/09/04 04:42 AM
Exhibits 230.2 through 230.13 illustrate examples of permitted service configurations. The figures are intended to clarify some of the Code rules that affect services but that are often misunderstood. No attempt has been made to include every type of service arrangement. It should be understood that the term one location, as applied to services, is determined by the authority having jurisdiction.

Seems it is still often misunderstood. Sounds like it is all up to AHJ on this...

Now this isn't a throw back to the "Taps" thread is it?
Posted By: gfretwell Re: NFPA 2002 NEC Handbook - 11/09/04 05:14 AM
Isn't this just a picture of 230.40 Exception No. 2: Where two to six service disconnecting means in separate enclosures are grouped at one location and supply separate loads from one service drop or lateral, one set of service-entrance conductors shall be permitted to supply each or several such service equipment enclosures.

They do appear to come from the same transformer on the supply end.
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