210.25 (B) Confusion

[aknorth]

Thank you for taking the time looking at this. So here is the challenge.

There is a small office building with two tenant spaces, we'll call them Tenant A and Tenant B. There are two meters on the building, one meter feeds Panel B for Tenant B, the other meter breaker feeds Panel A for tenant A and via a tap the House panel H. Panel H is not subfed by Panel A. The local jurisdiction say that because NEC 210.25 (B) says that house loads cannot "be supplied from equipment that supplies an individual dwelling unit or tenant space." The house panel cannot be fed from the same meter as Panel A and if you wanted to subfeed panel H from the same meter you would also have to subfeed panel B as well so that the the meter fed more than one tenant space. This doesn't seem to to jive with what the NEC is saying. Service Equipment is defined separately from Equipment, so it would be my understanding though you couldn't feed house loads off a Tenant Panel the service disconnect is Service Equipment and isn't disallowed. Has anyone else run into this or know of articles that address this?

Thanks

 

[iwire]

You can't feed the house loads off of the tenant meter.

Even if not an NEC issue certainly other rules in your area would apply.

 

[charlie b]

You are trying to interpret with the wording of the NEC in a way that suits your desires, and I don?t think it will work in your favor.

. . . if you wanted to subfeed panel H from the same meter you would also have to subfeed panel B as well so that the meter fed more than one tenant space.

I think you are misinterpreting the way the code says, ?house loads cannot be supplied from equipment that supplies an individual dwelling unit or tenant space." You are trying to replace the single word ?an? (as emphasized above) with the phrase ?only one.? A meter that serves two tenant spaces does, in fact, serve ?a tenant space,? in the context of that NEC requirement.

Service Equipment is defined separately from Equipment, so it would be my understanding though you couldn't feed house loads off a Tenant Panel the service disconnect is Service Equipment and isn't disallowed.

The two definitions are not mutually exclusive. The term ?equipment? is defined in broad terms; the phrase ?service equipment? is defined in more specific terms. Therefore, an item that meets the definition of ?service equipment? also meets the definition of ?equipment.? Without regard to the fact that the meter or the disconnect is ?service equipment,? it is ?equipment,? and it cannot supply both house loads and tenant loads.

 

[GoldDigger]

Charlie, I think you are stretching the wording a little too far. Interpreted literally, it would require that house loads and tenant loads be supplied by different services, without even a meter or service disconnect in common. I do not think that is the intent, given that almost every apartment building has house loads such as outside lighting even when there is no separate panel for those loads.
I take it to mean (whether it correctly says so or not) that when the tenant spaces have individual panels and perhaps meters, then the house loads must be supplied separately from all of them.
This affects both billing, if separately metered, and accrdd to the branch breakers and main disconnect for each space.