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Sometimes you need to run a circuit through both protected & unprotected space. For example, you might put a recep in workshop (unfinished walls = unprotected) over a crawlspace (protected).

To protect the wires in the unprotected space, you use a short length of EMT from the crawlspace, through the floor, to the junction box.

While people usually run separate THHN conductors through EMT, in this case it makes sense to use NM through the crawlspace and in to the EMT.

At the jbox, I'd normally use a NM clamp to hold the NM cable, or a set-screw connector to hold the EMT. What connector is appropriate for that end?

At the other end of the EMT, there is no box - just open space. What is the right fitting at that end?

EDIT: I think there are three goals here - clamp the NM cable in place, protect the cable from the sharp edge of the EMT, and secure the EMT to the jbox on one end.

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  • I think you can also buy ENT (Electrical Non-Metalic Tubing) in 10 foot lengths. That's what electricians in this area use for futures. Might not be sturdy enough but it is a choice.
    – lqlarry
    Feb 7, 2012 at 1:34

2 Answers 2

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How about an EMT slip on bushing?

EMT Bushing

This about explains it all.

Drawing

Catalog Page

EDIT: I think there are three goals here - clamp the NM cable in place, protect the cable from the sharp edge of the EMT, and secure the EMT to the jbox on one end.

I showed you how to protect the romex coming out of the EMT.

To secure the NM cable in place, where you want to clamp the NM in place depends on the box. If its a plastic box the most of them have their own clamping system. If it's a metal box then use standard 2 screw connectors, like these:

NM Connector

Staple romex as specified by code:

Staple Code

As for connecting the EMT to box, you probably need a metal box for the knock out. Use set screw connectors, you sound as if it is inside.

SS EMT Connector

The EMT should be secured to the walls. You clamps will look like these. If it needs to stand off the wall use the first, which you might need if you don't have an offset,

Pipe Clamp

Pipe Calmp

1 Hole strap

1 Hole Strap

J-Nail

J-Nail

Many other ways to do all these things also.

The only other thing I can think of is, an EMT connector, a rigid threaded coupling and two screw romex connector. Romex stapling by code.

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I use a set screw box connector with a bushing screwed on the end. Keep in mind there are restrictions for using EMT with Romex. Check the NEC book.

This bushing with this connector or if you need a clamp

bushing connector

Clamp

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  • Is this the combination you're thinking of? (i.imgur.com/zKVni.jpg). I'm having trouble getting the plastic bushing/clamp to screw on; it's slightly too small. Maybe I need to be stronger?
    – Jay Bazuzi
    Feb 7, 2012 at 7:17
  • Please See my edit.
    – SteveR
    Feb 7, 2012 at 12:05
  • That last one looks a lot like an EMT-to-Flex connector (which is easier to find), but I think they're not interchangeable. Thanks for the tips.
    – Jay Bazuzi
    Feb 7, 2012 at 16:23
  • Click on the link, says it's EMT to Romex. I've used them before.
    – SteveR
    Feb 7, 2012 at 18:24

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