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slow_eddie

Underground electrical and pvc boxes...

slow_eddie
15 years ago

Hello all. I'm an adventerous homeowner working on a project to supply my back yard with power. This is my biggest project yet, the most complicated thing I've done to date was install ceiling fans, but at work I deal with electricity all the time.

My plan is to run 3 separate GFCI breakers protecting 20 amp circuits with 12 gauge THHN wire through 3/4 inch pvc conduit.

Circuit 1 is for electrical outlets, one at the side of the house at the beginning of the run and two in the rear on separate sides of my back yard, total run about 140 feet.

Circuit 2 is for my soon to be built outdoor BBQ. It will power the little outdoor fridge as well as a few lights over the BBQ. Total run about 100 feet.

Circuit 3 will provide my patio with 3 electrical outlets as well as power two wet rated ceiling fans and light fixtures above my patio. Total run about 100 feet.

So now my questions.... I haven't talked to the electrical inspector yet and I don't want to seem completely clueless when I do (I want to disguise it as best I can).

I want to run all 3 circuits through one run of 3/4 inch pvc conduit and branch off where convenient for the other circuits. Is it against code for circuits to pass through receptacle boxes used by other circuits, even if there are no splices besides the receptacle circuit?

For example, circuit 1 will have a receptacle about 3 feet under my breaker panel at the start of the run, yet I also want to run the other 2 circuits through that box rather than run separate conduit for each circuit. There will be no splices made in the box for circuits 2 and 3, they will just pass through. Is this ok?

Also, due to the length of the cable run I wanted to use L bodies and T's as pull boxes. I know that you can't bury splices and they need to be accessible, but what if there are no splices and are just used to pull the wire and then continue on unspliced? Are they ok to bury? I noticed they have foam gaskets for weatherproofing. If I can't use L bodies I'm not sure what to use. I didn't see any regular T's at the electrical supply store.

Also, where my receptacles pop up out of the ground I wanted to use FS single gang boxes with a single hole in the bottom of the box. Is it ok to run the 3 conductors in and out of the box through the single hole? Or does their need to be one entry and one exit point? I would hate to have to use the boxes with two holes at the bottom. That would really take away from the sharpness of the install.

Thats it for now, I appreciate all replies.

Eddie

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