Commercial Multi-occupancy Building Branch circuits

[david luchini]

Based on the exact wording of 210.25, I agree with this.

I'd have to again say that the exact wording of 210.25 prohibits Charlie's example of running a branch circuit from a panel in unit A, through the attic of unit B, and connecting it to a laundry receptacle back in unit A. But the more I consider the wording of the section, the less it seems to imply what that loads in one dwelling unit can't be supplied from the panel in another dwelling unit.

The section says:

210.25 Branch Circuits in Buildings with More Than One Occupancy.
(A) Dwelling Unit Branch Circuits. Branch circuits in each dwelling unit shall supply only loads within that dwelling unit or loads associated only with that dwelling unit.
(B) Common Area Branch Circuits. Branch circuits required for the purpose of lighting, central alarm, signal, communications, or other needs for public or common areas of a two-family dwelling, a multifamily dwelling, or a multi-occupancy building shall not be supplied from equipment that supplies an individual dwelling unit or tenant space.

The branch circuit in the attic of Dwelling Unit B is undoubtedly "in" Unit B, but it is supplying loads that are within Unit A. But what was bothering me as I thought about it more was that nothing in this section would prevent a "feeder" being run from Panel A to feed a subpanel in B, as long as the branch circuits originating in subpanel B fed loads only in or associated with Dwelling Unit B.

Is there some other section that would prevent this?

 

[iwire]

I thought you might.

I hereby throw down the gauntlet of Charlie's Rule upon thee! :happyyes: That is not what 210.25 says. What it does say is that a circuit in one unit can't supply a load in another unit.

So in my high tech image below do you feel it is a pass or fail of 210.25(A).

210.25 Branch Circuits in Buildings with More Than
One Occupancy.

(A) Dwelling Unit Branch Circuits. Branch circuits in
each dwelling unit shall supply only loads within that dwelling
unit or loads associated only with that dwelling unit.

In my opinion it is a clear violation.

It looks to me like a branch circuit is in the Smith's house that supplies a load in the John's house.

IMO, in this case 'supplies' has nothing to do with the panel location, it has to do with the function of the NM cable in the Smiths house that is supplying the light in the John's home.

 

[Smart $]

...In my opinion it is a clear violation...

I'm going on record as agreeing with you. Contrary to Charlie's point regarding load, the key phrase and word is, "Branch circuits in each dwelling unit..."

However, in a multi-dwelling unit where an attic, basement, garage, etc. is not distinctly partitioned to a single unit, I say no violation.

 

[elohr46]

So in my high tech image below do you feel it is a pass or fail of 210.25(A).


In my opinion it is a clear violation.

It looks to me like a branch circuit is in the Smith's house that supplies a load in the John's house.

IMO, in this case 'supplies' has nothing to do with the panel location, it has to do with the function of the NM cable in the Smiths house that is supplying the light in the John's home.

I don't see how this situation is any different from the Smith's home being on the first floor and John's home being on the second floor with the panels in the basement feeding branch circuits upwards through Smith's home to supply outlets in John's home.

 

[iwire]

However, in a multi-dwelling unit where an attic, basement, garage, etc. is not distinctly partitioned to a single unit, I say no violation.

I agree, those would be common areas.

 

[iwire]

I don't see how this situation is any different from the Smith's home being on the first floor and John's home being on the second floor with the panels in the basement feeding branch circuits upwards through Smith's home to supply outlets in John's home.

I did not say it is different and IMO what you describe is also a 210.25(A) violation unless you keep those circuits out in the common areas like stairwells and halls etc.

 

[elohr46]

I did not say it is different and IMO what you describe is also a 210.25(A) violation unless you keep those circuits out in the common areas like stairwells and halls etc.

I have to disagree, I'm not seeing any wording that prohibits branch circuits or feeders from "passing through" one dwelling to another except in article 230 for service conductors.

 

[hurk27]

I now see where Bob is going and somewhat have to agree as per the wording that any branch circuit "in" a dwelling cannot feed a load in another dwelling, this section makes no mention as to where this branch circuit originates from or who's paying the bill for it, it only mentions just where it is located at and what load it is not allowed to feed.

Now as for the wording and or intent I would say it could have used much better words if the intent was to keep keep it out of another dwelling or on the flop allow it to pass through another dwelling, but as we see here it kind of can be read either way whether or not you wish to use the words "branch circuits IN" which seems to be the key of interpretation.

I think "Charlie's Rule" is backfiring on him in this one:happyyes:

 

[iwire]

I have to disagree, I'm not seeing any wording that prohibits branch circuits or feeders from "passing through" one dwelling to another except in article 230 for service conductors.

How can a branch circuit pass through a dwelling if it is not 'in' the dwelling?

I also ask you this, given your view when would you say that 210.25(A) does apply?

I think the real issue is you applying how you (we) have done it in the past and not what the words actually say.

 

[elohr46]

How can a branch circuit pass through a dwelling if it is not 'in' the dwelling?

I also ask you this, given your view when would you say that 210.25(A) does apply?

I think the real issue is you applying how you (we) have done it in the past and not what the words actually say.

I think this way only because it is physically impossible to rewire row homes and older large single homes when they are converted from SFD's to MFD's. If we are not permitted to have an interior mechanical chase (for plumbing, heating and electrical) to get from the basement to the upper floors for each new dwelling then there are thousands of MFD's out there with code violations being constructed every day.

 

[Smart $]

I think this way only because it is physically impossible to rewire row homes and older large single homes when they are converted from SFD's to MFD's. If we are not permitted to have an interior mechanical chase (for plumbing, heating and electrical) to get from the basement to the upper floors for each new dwelling then there are thousands of MFD's out there with code violations being constructed every day.

But it is not impossible to rewire these. Doing so is only an inconvenience.

Submit a proposal...

 

[kwired]

I think this way only because it is physically impossible to rewire row homes and older large single homes when they are converted from SFD's to MFD's. If we are not permitted to have an interior mechanical chase (for plumbing, heating and electrical) to get from the basement to the upper floors for each new dwelling then there are thousands of MFD's out there with code violations being constructed every day.

That is why I presented the question of "what is in the dwelling" and gave examples of areas that can be questionable like attics, crawl spaces, mechanical chase, and even a partition wall between two dwellings with electrical outlets in that wall.

 

[charlie b]

I recognize that the word “in” does complicate, if not downright repudiate, my point of view. I must add, however, that if 210.25(A) was not intended to refer to branch circuits “originating in” each unit, then it would not be possible for a multi-family dwelling unit (or other multiple occupancy building) to be in compliance with that article. As Kwired has twice pointed out, the wall between two units will have to have receptacle outlets, and in the context some of you are using for the word “in,” the conduits within that wall are “in” both units.

But we don’t operate on the basis of intent. I will submit two proposals to revise this article. The two will contradict each other, and I will clearly state that I am putting in two contradictory proposals so as to give the CMP an opportunity to select the one that matches their intent. One proposal will revise the wording to “Branch circuits originating in . . . ,” and the other will more clearly declare that branch circuits shall not run through other units, except at adjoining walls. Time will tell which they will select. My money says that they will reject both. :happyyes:

 

[charlie b]

I will submit two proposals to revise this article.

I managed to get it into a single proposal. Here is a draft, for your consideration and comments.
http://forums.mikeholt.com/showthread.php?t=140293&p=1341621#post1341621