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I am running conduit for thhn wires in the crawl space below the house. I have some 90° bends, and it is tight to fit an elbow, so I just wanted to leave wires exposed for ½ inch or so. No plans to pull more wire, and the spot is easily accessible. As I can read the code this is not allowed unless the wire is allowed to be used without conduit, like NM-B type, but maybe there are exceptions I am not aware of? Please give reference to code, and not "My uncle Bob did it like that" Thanks

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  • Could you post a photo or two of the bend areas you are having trouble with? I'm not understanding why leaving exposed wire would make things easier.
    – Armand
    Commented Nov 18, 2022 at 5:06
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    I think you've got some good answers on this, but the bottom line is: rats. Commented Nov 18, 2022 at 7:33
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    In some cases the conduit serves to carry ground, so a gap could leave portions of your system ungrounded. Commented Nov 18, 2022 at 15:07
  • Where did you get the idea that "½ inch or so" might be allowed, any more than exceeding the speed limit by 50% or so? How might a bend of 90° matter, as opposed to 45° or 180°? How about if you just exposed your children to raw power unshielded running for "½ inch or so"? Commented Nov 19, 2022 at 19:58

2 Answers 2

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No plans to pull more wire

Does not matter.

and the spot is easily accessible

Does not matter.

As I can read the code this is not allowed unless the wire is allowed to be used without conduit, like NM-B type

Correct.

I am running conduit for thhn wires in the crawl space below the house. I have some 90° bends, and it is tight to fit an elbow

Make sure you are availing yourself of ALL the available kinds of bends.

enter image description here

Broad sweep.

You can buy these pre-made if you like or bend them yourself with an appropriate tool. No need to master the art of getting multiple bends Just Right - just do one bend at a time and use couplers. You're in a crawlspace so presumably you have some height to play with... use it, the conduit doesn't have to be snug against something usually.

Pull Elbow. This has the lid on the 45 degree angle across the outer face.

Wrong coupler on that particular one, but it's the picture we had.

enter image description here

Corner pull elbow. Same but with lid on side face.

enter image description here

"LB" conduit body. Asymmetrical; door on the outside.

"LL" conduit body, ditto, left side.

"LR" conduit body, ditto, right side.

enter image description here

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    Hi Harper, one thing that would improve this (already amazing) answer would be to explain what conduit is for. i.e. explain to OP it’s not for convenience, it is a safety feature. Commented Nov 19, 2022 at 23:11
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You shouldn't use "elbows" on conduit. You can either use a sweep (gently curved, easy to pull through)

Conduit sweep image from coxhardware.com

or you can use an LB, LR, LL (sharp elbow but with a removable access cover for pulling.)

LR image from Zoro.com

There's also a "pulling elbow" with a cover at 45 degrees, similar function.

Pulling elbow image from Zoro.com

The conduit must be completely assembled EMPTY and then the wires are pulled into it. If you can't do that, you need to change things so you can. The access covers can be removed while pulling, of course - that's what they are for. Then they must be replaced before commissioning the circuit.

The wires must be completely inside the conduit or junction boxes the conduit is assembled to, with no wires exposed.

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