clamping cables from conduit inside of junction box

Status
Not open for further replies.

jw1848h

New User
Location
Baldwin, NY
Occupation
Retired Electrical Engineer
This is about clamping cables entering a junction box via conduit.

I plan to use an exterior PVC junction box, for example an E989NNJ-CAR found here: https://carlonsales.com/techinfo/brochures/conduit/Junction_Boxes_Brochure.pdf, with PVC conduit. I plan to drill holes, one in the back and another in the bottom, and use conduit adapters, for example https://www.acehardware.com/departm...fittings-and-conduit/conduit-connectors/33220

Two cables will enter the junction box, one will be interior NM 10-3 in ½ inch conduit, and the other a buried-rated NM 10-3 (it’s flat, not round) in 1 inch conduit. The interior NM will enter at the back of the box through a very short piece of conduct, maybe 1 inch long, to pass through vinyl siding, it then will pass exposed (not in conduit), through a wall and then perpendicular through several floor joists over a crawl space, completely inaccessible (there is an existing cable there, I plan to pull it out and then pull-through the new cable. The buried NM cable will enter the box at the bottom, through maybe 1 foot section of conduit extending out of a concrete driveway.

My first question is, with this arrangement, how do I satisfy the requirement to clamp cables inside the box? I can’t clamp them anywhere within 12 inches outside the box. Or maybe they don’t need to be clamped inside the box in this situation?

My second question is, do I even need that short piece of conduit protecting the interior NM cable as it passes through the siding? Maybe if I caulk all around the back of the box, it isn't needed.
 
I am closing this thread, in accordance with the Forum rules. This Forum is intended to assist professional electricians, inspectors, engineers, and other members of the electrical industry in the performance of their job-related tasks. However, if you are not an electrician or an electrical contractor, then we are not permitted to help you perform your own electrical installation work.

If I have misjudged the situation, if for example this project is related to your work, then send me a Private Message. If you can show me that I am wrong, and that you are a licensed electrician (or at least a licensed apprentice), then I will reopen your post, and offer an apology for the delay and inconvenience.

A reminder to all members, if you see a questionable post, feel free to report it by clicking the button at the bottom left corner of the post.
 
Status
Not open for further replies.
Top