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Suppose I'm running some wire in EMT into the side of an electric panel, and the electric panel is flush mounted into a dedicated stud bay extension / bump out.

Here's a sample photo with a panel that's only 2-3" out, where the rest of the big hole was filled with foam.

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I typically do this by drilling a 3/4" hole into the (metal) panel, and a much bigger hole (roughly 1-1/4" or 1-1/2") into the wood stud. The bigger hole is needed to fit an entire EMT male terminal into the wood stud. I can probably get away with a slightly smaller hole if I use a compression terminal rather than a screw terminal, but those are harder to attach tightly.

Either way, I need to drill a 1"+ hole in the wood stud.

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Is there a better way to do this, without drilling such a big hole into the wood stud?

Ideally I'd still prefer to go straight out of the side of the panel (rather than going in-wall to the top or bottom and coming out into conduit via a box extension). But if this is really uncommon, then I'd like to know how most electricians terminate conduit into such a panel.

2 Answers 2

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If the stud ("a dedicated stud bay extension") was put there just to flush mount the panel, and is not structural, cut it, or cut away most of it to expose the knockouts on the side of the panel.

EMT as a wiring method is better served by surface mount panels. That's the better way to do it you're looking for.

Most wiring from flush-between-studs panels goes from top and bottom because those are the accessible sides of the panel that don't involve trying to make access where access has been impeded by the mounting method. Those are also the sides that allow the installation to remain "hidden" which is normally the reason a box is flush-mounted at all. Flush mounting and then running exposed EMT is somewhat unusual because it's combining things that don't go well together.

One method to solve this in the illustrated example or things close to it is to punch one big hole into one of the large side knockouts and install a nipple (less than 24" long) of IMC or RMC to a section of gutter or a large junction box surface-mounted next to the "bumped-out-flush-mounted" panel, and connect your EMT runs to the gutter or junction box. Keeping the nipple less than 24" long allows 60% fill and no thermal derate for the number of circuits.

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  • I use EMT, and my panels are surface mounted, not by coincidence.
    – Ecnerwal
    Commented Dec 31, 2023 at 2:12
  • Thanks! Really helpful context and makes sense ultimately. I wish I could make every panel surface mount but it is what it is. Regarding the last suggestion -- can I use a nipple like this one connected directly to the EMT via an EMT coupling? If so, do I need to cut the threaded part of the RMC nipple or can I just insert it into the coupling?
    – peter
    Commented Dec 31, 2023 at 4:09
  • The junction box + nipple allows for connecting multiple conduit runs, with only one awkward hole through the stud. If you only have one run to connect, might as well just pop in a big-enough hole and connect similar to what you already show, but preferably with the compression fitting. Do try to find a knockout when drilling the hole in the wood, it's much less of a mess in the panel than drilling through the metal.
    – Ecnerwal
    Commented Dec 31, 2023 at 16:20
  • Is it worth doing the whole job in RMC then? I've never used it before but I'd be open to learning. The distances are short enough (~6') that the cost difference for conduit is unlikely to matter. But while I'm familiar with bending EMT and using the right connectors, I'm less familiar with RMC.
    – peter
    Commented Jan 1 at 0:53
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You might gain a little by inserting the emt connector into a rigid coupling, drill the hole size tight to the rigid coupling with just a small notch in the drywall on the backside of the hole for the set screw. Then push the coupling into the hole securing it to the panel with a chase nipple from the inside of the panel.

Or maybe not.

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  • Can I use a nipple like this one connected directly to the EMT via an EMT coupling? If so, do I need to cut the threaded part of the RMC nipple or can I just insert it into the coupling?
    – peter
    Commented Dec 31, 2023 at 4:10
  • Also, what does a chase nipple do?
    – peter
    Commented Dec 31, 2023 at 4:11

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