Multiple Feeders To A Single Building

Status
Not open for further replies.
V

vw55

Member
Location
California
If there is a requirement to add HVAC to an existing classroom wing on an elementary school campus, and the existing panel currently serving that building does not have sufficient power, is there a violation of 225-30 if we were to set a dedicated panel for the HVAC and mount it on the exterior wall of the building? Or do we have to upgrade the existing feeder and panel to accommodate the new HVAC load to not allow more than one disconnect at the building?
 
Re: Multiple Feeders To A Single Building

In general, there is suppose to be one service/feeder for a building. There are other considerations, maybe you will qualify for one of them. You need to consult with your inspector, or maybe give a little more detail, and we can try to guide you.
 
Re: Multiple Feeders To A Single Building

It does not sound like you meet any of the criteria of 225.30(A) through (E). So I think there is nothing I can say to help, until you give more details, as Pierre has suggested. Here are some of the questions I would ask:

What do you mean by "the existing panel . . . does not have sufficient power"? Have you done a load calculation or a load measurement to determine the existing load, and concluded that adding more load would put you over the rating of the panel or the rating of its feeder? Is it just that the panel is out of breakers?

How does power presently come into that wing? Is the "existing panel" located in the wing? Is the wing permanently, structurally connected to the other building(s) on campus or does it stand alone?
 
Re: Multiple Feeders To A Single Building

please note 225-34 also in regard to locating it outside.
 
Re: Multiple Feeders To A Single Building

'05 Code Bob, did I err?
 
Re: Multiple Feeders To A Single Building

When I see "-" in place of "." I think of the 1999 NEC.

That aside I do not get the reference between 'outside' and 225.34.

Am I missing something?
 
Re: Multiple Feeders To A Single Building

ever wish you just hadn't posted :)
sorry, I was just concerned about the grouping of disconnects if he did add a feeder...not knowing where the 1st supply disconnect was located, I was simply trying to bring this to his attention.
 
Re: Multiple Feeders To A Single Building

Countless times and usually it is right after I read Don's or Charlie's posts.
Click to expand...
AMEN! Feeling foolish has gotten to be a regular, daily emotion since I met them.

[ November 21, 2005, 05:40 PM: Message edited by: augie47 ]
 
Re: Multiple Feeders To A Single Building

Eating crow is not that bad, a little BBQ sauce, some hot peppers and you won't even taste the crow. :D
 
Re: Multiple Feeders To A Single Building

Actually eating crow is not bad at all - especially when you eat as much as I do - a hint to the less informed at eating crow - pluck it first, the feathers are the worst ;)
 
Re: Multiple Feeders To A Single Building

I'm sorry for not laying it out completely for everyone.

Yes, the existing panel is located in an equipment closet at the classroom wing and does not have sufficient capacity (buss ampacity not breaker space) to add load to. It has a main circuit breaker installed to it.

The existing classroom wing is physically attached to a covered exterior open walkway that passes between this building and the adjacent buildings. The adjacent buildings are also physically attached to this walkway, but not to the classroom wing in question. So technically they are all attached, however, they "stand alone".

The main switchboard that feeds this existing panel (as well as the other building's panels) is located remotely from this classroom wing in an outdoor equipment yard.

In response to Charlie B's comments, are you saying that if the HVAC is fed 480 volt and the existing panel is fed 208 volt, I would fall under 225.30 (D) exception?

I am in California and we are currently using 2002 NEC (2004 California Electrical Code).

Thanks for all your input.
 
Re: Multiple Feeders To A Single Building

Originally posted by vw55:. . . are you saying that if the HVAC is fed 480 volt and the existing panel is fed 208 volt, I would fall under 225.30 (D) exception?
Click to expand...
I would say yes. But I only have a copy of the 2002 NEC. The California Electrical Code consists of the 2002 NEC with specific additions, deletions, and other changes. I do not have a copy of that document, and do not know if it has modified 225.30(D). Good luck.
 
Status
Not open for further replies.
Top