220VAC line burial depth ?

[kmdigital]

Bob,
I like 18 inches for conduit and 24 inches for direct burial but this will vary according to your location.
David B

I believe this is the correct depth according to the NEC. You can always go deeper if you want, but it means moving a lot more dirt, both on the way out and going back in. And it takes a lot longer for the dirt to settle in the trench the deeper you go, so it is your choice. Personally, I go around 2 to 2-1/2 feet with conduit, because it is easy to back fill and settles quickly. 3' isn't too bad, but 4' is moving an great deal of dirt, especially if you are in a sandy area where it tends to cave in easily.

 

[dqdave1]

Our area requires 4 foot deep for run from pole to house. It also requires RED tape to be placed one foot above conduit in trench for warning .

 

[Ford850]

42 - 48 " for main line from the road to the house or meter. 18" from there or from the house to an outbuilding.

 

[GreatWhitehunter]

I think you need to rethink your conductor size. A 100Amp service requires #3 copper and #2 aluminum. And after 100FT run you need to factor in voltage drop. As for burial depth I'd go with the NEC since it is the minimum. I'd go with #1 copper for the VD and if your going THHN you'll be good for 130A.The voltage means little to the burial depth. In case your wondering you'd need 2" schedule 40 pvc and you could run 5 #1's you won't be able to use 1-1/2 since you can only get three in there and you should not downsize the neutral. And you need a ground also (bonding conductor).

Matt T.

 

[GaryBDavis]

bcarwell,

If you can't get your middle buster to go down as far as you like, the nearest rental place for a Ditchwitch is Cat Trax on Hwy 29. You can get a 3700 (diesel, ride-on) set up for a 4" wide trench that can go down 24". I think a day's rental is around $160 with tax. It comes with a front blade so you can fill the trench back in. If you land is fairly rocky, they also have rock saws but thoese are more like $300 a day. They are nice folks to deal with.

As far as depth goes, I've never put in anything deeper than 24".