sub-panels
- Thread starter gbsparky
- Start date
- Status
jeff43222
Senior Member
- Location
- Minneapolis, Minnesota
Re: sub-panels
As long as the feeders are protected, I think it's OK to have as many subpanels as you want.
As long as the feeders are protected, I think it's OK to have as many subpanels as you want.
- Location
- Massachusetts
Re: sub-panels
The only thing that matters is that the total calculated load is less than the rating of the main breaker.
No there is no limit to the number of 'sub panels' that can be fed from one main.
The only thing that matters is that the total calculated load is less than the rating of the main breaker.
goldstar
Senior Member
- Location
- New Jersey
- Occupation
- Electrical Contractor
Re: sub-panels
I recently wired a new residence that ended up to be approx 6000 sq. ft. My calculated load was around 257 amps and I wanted to install a 300 amp service. The builder only wanted a 200 amp service (his reasoning was that he didn't want the larger 300 amp meter pan sitting in the stone facia outside his dining room window) and the POCO and AHJ said it was OK also. I ended up with a 40 circuit main panel (using 37 of the 40), a 24 circuit 100 amp sub panel for the 2nd floor (using all 24 circuits), and a 16 circuit, 60 amp sub panel in the unfinished area of the basement (using 12 of 16). Now, granted, the homeowners will probably never come close to using 200 amps, but I would imagine that somewhere down the line they will probably install a pool and a hot tub. Imagine throwing a pool party with about 50 guests ? Some hell of an electric bill wouldn't you think ?
Regards,
Phil
Bob, is this a code issue or logically and professionally the right thing to do ?
I recently wired a new residence that ended up to be approx 6000 sq. ft. My calculated load was around 257 amps and I wanted to install a 300 amp service. The builder only wanted a 200 amp service (his reasoning was that he didn't want the larger 300 amp meter pan sitting in the stone facia outside his dining room window) and the POCO and AHJ said it was OK also. I ended up with a 40 circuit main panel (using 37 of the 40), a 24 circuit 100 amp sub panel for the 2nd floor (using all 24 circuits), and a 16 circuit, 60 amp sub panel in the unfinished area of the basement (using 12 of 16). Now, granted, the homeowners will probably never come close to using 200 amps, but I would imagine that somewhere down the line they will probably install a pool and a hot tub. Imagine throwing a pool party with about 50 guests ? Some hell of an electric bill wouldn't you think ?
Regards,
Phil
charlie
Senior Member
- Location
- Indianapolis
Re: sub-panels
I have always been a fan of following the Code.
I have always been a fan of following the Code.
- Location
- Massachusetts
Re: sub-panels
Phil IMO what you installed was a direct violation of 230.42, even with the inspectors blessing.
Not to sure if that was a good idea, even if the customer did not want the 320/400 socket.
Bob
Phil IMO what you installed was a direct violation of 230.42, even with the inspectors blessing.
Not to sure if that was a good idea, even if the customer did not want the 320/400 socket.
Bob
buck33k
Senior Member
- Location
- Washington state and North Carolina
Re: sub-panels
Just a thought(although late),but there would have been a couple of ways around the builder's objection to the 320 meter on the building.
Put it on a 6x6 post some distance away and conceal with shrubs.
CT meter at transformer and two 200 amp panels grouped indoors.(garage)
Just a thought(although late),but there would have been a couple of ways around the builder's objection to the 320 meter on the building.
Put it on a 6x6 post some distance away and conceal with shrubs.
CT meter at transformer and two 200 amp panels grouped indoors.(garage)
goldstar
Senior Member
- Location
- New Jersey
- Occupation
- Electrical Contractor
Re: sub-panels
While both of these may be legit I don't think the POCO, AHJ or builder would have allowed me to use either of these methods. All the houses in this area are $2 mil and up. I did take one precaution though - I ran 4/0 in 3" PVC underground to the transformer. At least that way the feeders can handle 250 amps. If somewhere down the line the new residents have a need to bump up the service to 300 amps, at least they won't have to dig up the lawn and driveway.
charlie tuna
Senior Member
- Location
- Florida
Re: sub-panels
a none residential viewpoint of adding panels has always been a pet peive of mine! office building electric rooms--and it isn't against code--but a bad practice. new tenant build out and they add a 42 circuit panel and sub feed it off an existing with a three pole fifty amp breaker. i have seen electrical rooms with so many panels you can't see the walls!!! they don't do the proper engineering of plans to re-use existing circuits. cap those off by the demolition contractor, and just run new!!! i guess it's actually cheaper!!! years ago we used to re-use the existing circuits,keep an "as built" drawing and submit it to the engineer after the job was complete!
[ February 07, 2005, 07:51 AM: Message edited by: charlie tuna ]
a none residential viewpoint of adding panels has always been a pet peive of mine! office building electric rooms--and it isn't against code--but a bad practice. new tenant build out and they add a 42 circuit panel and sub feed it off an existing with a three pole fifty amp breaker. i have seen electrical rooms with so many panels you can't see the walls!!! they don't do the proper engineering of plans to re-use existing circuits. cap those off by the demolition contractor, and just run new!!! i guess it's actually cheaper!!! years ago we used to re-use the existing circuits,keep an "as built" drawing and submit it to the engineer after the job was complete!
[ February 07, 2005, 07:51 AM: Message edited by: charlie tuna ]
- Location
- Windsor, CO NEC: 2017
- Occupation
- Hospital Master Electrician
Re: sub-panels
I've read this a couple times. You just mean you used a heapum biggum pipe and the conductors can be replaced by larger ones to handle 250 or 300 amps, right?
goldstar
Senior Member
- Location
- New Jersey
- Occupation
- Electrical Contractor
Re: sub-panels
That's right George. It was a CYA type deal. I figured if the homeowners burn up the 200 amp panel and they subsequently require a 300 amp service, the POCO will probably not replace the underground feeders but changing out the meter pan and breaker panel(s) will be the easier part of the job. I'll have to chop out the stone facia to get a 300 amp meter pan in the same spot.
[ February 08, 2005, 05:13 AM: Message edited by: goldstar ]
That's right George. It was a CYA type deal. I figured if the homeowners burn up the 200 amp panel and they subsequently require a 300 amp service, the POCO will probably not replace the underground feeders but changing out the meter pan and breaker panel(s) will be the easier part of the job. I'll have to chop out the stone facia to get a 300 amp meter pan in the same spot.
[ February 08, 2005, 05:13 AM: Message edited by: goldstar ]
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