Feeder sizing
- Thread starter crtemp
- Start date
- Status
- Location
- Massachusetts
It does not apply to a detached shop.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
I agree with Bob and I will also say that the dwelling cannot use T. 310.15(B)(7) either
- Location
- Massachusetts
qcroanoke
Sometimes I don't know if I'm the boxer or the bag
- Location
- Roanoke, VA.
- Occupation
- Sorta retired........
I'm looking in 2008. I don't see that table.
Is it new?
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
same as 310.15 (b)(6) in the 2008 . The 2011 changed a few numbers
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Since the garage load is part of the service then the house does not carry the entire load. This is how I see it and was also how some of the cmp members saw it when specifically asked that question. Why would a detached garage be different than an attached garage. The function of Table B(7) is diversity so it seems that the garage should be considered as part of the homes diversity detached or attached
qcroanoke
Sometimes I don't know if I'm the boxer or the bag
- Location
- Roanoke, VA.
- Occupation
- Sorta retired........
May I ask why you say it can't be used on a residence?
That sounds like one my my hair-brained ideas
Lets see... I build my house with an attached garage and I use the Table.
I build the exact same house wit the exact same garage load but the garage is detached across a 3' walkway and I can't use the Table.
makes sense to me
same logic as feeding your A/C load from your meter combo so you have to use a bigger feeder to the inside panel
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
It can be used on a residence but IMO, not in the example stated since the house will have a feeder that does not carry the entire load. If you look at art. 310.15(B)(7)-- not the table but the article -- 2008 it is (B)(6) it states all loads that are a part or associated with the dwelling.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Sorry I have been multi tasking. In order for a feeder to be allowed to use the residential T. 310.15(B)(7) or B(6) for the 2008 the feeder must carry the entire load of the dwelling or associated with the dwelling. Since the garage is associated and has a separate feeder then the dwelling cannot use this table for the feeder.
Does that make sense?
Does that make sense?
Strathead
Senior Member
- Location
- Ocala, Florida, USA
- Occupation
- Electrician/Estimator/Project Manager/Superintendent
But that is Dennis' opinion. I personally would ask the AHJ. I can't disagree with Dennis' logic, but the local AHJ may interpret differently. OTOH if it were my house you would not use that table.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Ah, man you hurt my feelings....
It is an opinion but it seems clear when they say all loads associated with the dwelling. I guess one could say that the garage isn't associated with the dwelling but it really is-- yes that's my opinion. Not sure it makes sense otherwise.
- Location
- New Jersey
- Occupation
- Journeyman Electrician
Not sure that any of the discussion of that table is relevant. #1/0 AL is already rated at 120 amps, next size up is 125 amps.
Ya I forgot you could up to the next standard breaker. That's what I ended up doing.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
True assuming the urd is rated 75C or better. I assume it is rhh/rhw
- Location
- Massachusetts
The service conductors would still be carrying 100% of the dwelling unit load.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
Do you mean dwelling or the dwelling and associated loads???? Yes the service conductors would qualify but not the feeders to the house and garage, IMO
- Location
- Massachusetts
Maybe you know something I do not but the OP never mentioned a feeder to the house.
- Location
- Chapel Hill, NC
- Occupation
- Retired Electrical Contractor
There may not be a feeder to the house. I brought it up as if there were a feeder to the house panel and stated that it could not use the resi table because of the garage. I was just adding some extra info. Certainly the service conductors are fine using the table.
- Status