New construction. You’re gonna bring your electric feed underground from the pole out at the front corner of the lot.
Your mechanical room in which the panel will be located is in the back side of the basement. To save money on cable, instead of running around the house and in from the back side, the long way, you take a short cut, and . . .
Run it under the house, a distance of 24 feet under the slab, and stub it up through the slab floor right under where the panel will be.
How will your inspector like that?
What’s your cost per foot of 200 amp underground service cable?
Replies
How will your inspector like that?
they would not care. As long as its in conduit. They do it all the time in commerical work.
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“Ilsa, I’m no good at being noble, but it doesn’t take much to see that the problems of three little people don’t amount to a hill of beans in this crazy world”.
It has to be in conduit and under concrete. Don' remember how much concrete.
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
The service is unprotected until it is fused or has a breaker. The utilities amperage can be enormous. But if under a slab of at least 2" of concrete, this will be legal since it is condiered outside.
For current distributor prices on THHN, Google aiwc.com and THHN price list. For 200 amp service, you will need about 1/2" cable.
Note: in the trade, it is called 250 kcm or 250,00 circular mils but it actually isn't. It is square mils.
~Peter
You will need to plan this with the power co. In my area they supply the cable.
Where's the meter? At the pole?
The power company wants them on either the house, or on a "pedestal" up the line a little ways on the property between where it goes in-ground at the pole and where it enters the house.
The pedestal is a pair of pressure treated 6x6s bolted together, sunk 4 to 5 feet into the earth, and two sections of conduit come to the meter bottom, with the meter mounted at 5 feet off grade.
In this case the meter pedestal is about 55 feet from the front of the house.
Article 230.6 defines when conductors are considered outside the building: 1) when under not less than 2 inches of concrete beneath the building, 2) within a raceway inside the building that is encased in concrete or brick not less than 2 inches thick, 3)where installed in any vault that meets the construction requirements of Article 450, Part III (this one probably won't have any effect on your situation), or 4) where installed in conduit and under not less than 18" of earth beneath the building.
You said, "In this case the meter pedestal is about 55 feet from the front of the house."
I assume that will mean the electric utility will provide the wire up to the meter, and cable and conduit from the meter to the house will be paid for out of your pocket. I further assume you'll need a service disconnect/main breaker right there at the meter pedestal as well.
If that's the case, I think the cable and conduit may be able to pass right through the front of the basement and go straight to the panel, instead of running underneath the floor or around the building - since it will be downstream of the service disconnect, I believe the cable will be considered a feeder instead of service entrance conductors so the rules will bedifferent (if that is the case you will have to run separate ground and neutral wires to the panel from the service disconnect at the meter pedestal.)
Hopefully Bill H. or one of the other guys will confirm or deny this....
It is a walkout basement, with slab on grade. The proposed routing is through the walkout (downhill side facing road) frostwall, then under the 4" floor slab, buried beneath the 8" of gravel fill with 2" rigid foam on top.
24 feet of this under-slab, then a turn-up in the mechanical room, under the panel.
If it's past the meter base you might be able to use TECK cable instead of conduit. That's what I did, inspector had no issues with it.The only difference between mine and yours is that mine was downstream of a sub panel, but I don't see how this would change things.Scott.Always remember those first immortal words that Adam said to Eve, “You’d better stand back, I don’t know how big this thing’s going to get.”
I wouldn't want to put any cable under the slab unless it was in conduit.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
Edited 5/9/2007 7:54 am by DanH
"I wouldn't want to put any cable under the slab unless it was in concrete."Did you mean concrete or did you mean conduit?I see that 300.5(C) required an cable running under a building to be in a raceway..
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A-holes. Hey every group has to have one. And I have been elected to be the one. I should make that my tagline.
Edited 5/9/2007 12:13 am by BillHartmann
Yeah, that's what I meant -- conduit. Any place where you'd have to destroy more than minor plantings to access the cable.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
By any chance are you in Buffalo?
Sorry, Whistler, BC, Canada.Scott.Always remember those first immortal words that Adam said to Eve, “You’d better stand back, I don’t know how big this thing’s going to get.”
To update my previous post, I ran out of crossword puzzles at lunch in my car and found my latest printout from AIWC.com. For 200 amps, you would need 3/0 stranded which is good for 200 amps. Or 2/0 stranded which is 175 amps. Services may be less.
3/0 is 9/16" diameter and is listed for $5,469.84 per 1000 feet.
2/0 is 1/2+" dia. and is $4356.10 per 1000' as of March 20, 2007. The good news is that there is a 2% discount when paid in full within 10 days.
~Peter
A nation wide search is now on for a perfect identical twin for Paris Hilton. Even the fingerprints must match.
The disconnect at the meter might not incorporate a breaker.
So convenient a thing it is to be a reasonable Creature, since it enables one to find or make a Reason for everything one has a mind to do. --Benjamin Franklin
I further assume you'll need a service disconnect/main breaker right there at the meter pedestal as well.
Naw he doesn't need that, at least not by NEC rules. Since it's considered all outside the house until it comes up through the slab, the main disconnect can be right in the distribution panel.
Ed
I further assume you'll need a service disconnect/main breaker right there at the meter pedestal as well.
Naw he doesn't need that, at least not by NEC rules. Since it's considered all outside the house until it comes up through the slab, the main disconnect can be right in the distribution panel.
Well, it was an assumption....requirements can vary, depending on the locality and the electrical utility company. The original poster may be able to find some information on the local utility's website, many of them have all that stuff online these days.