Adding surface conduit to flush mount panel?

[mct75]

I have a flush mount breaker panel in my finshed garage, and I want to install some conduit on the outside of the drywall for outlets and a compressor. How should I get my wire from inside the stud bay to outside the drywall? I was planning on screwing a board to the two studs flanking the panel and attaching the box to that, but I don't see an easy way to get conduit from the knockout on the bottom of the panel to the rear of the box. A surface mount panel would make it easy (just go straight down) but I get dizzy thinking in 3 dimensions.

Is there some adapter for this? Any pictures of how this is typically done?

 

[pattenp]

Use a piece of Romex wire to run in the wall cavity from the panel into the back of a surface mounted box. Use NM clamps where the Romex exits the panel and where it enters the back of the surface mounted box. At the box change to conduit and THHN wire.

 

[dscheidt]

A bent piece of conduit. Boxes have knockouts on the back.

 

[alfredeneuman]

Try one of these

to come out of the panel and into the back of the box
You can adjust it with different lengths of conduit *******

It's called a "bushed elbow"

 

[wyliesdiesels]

Whats the HP rating on the compressor's motor as listed on the nameplate label?

 

[mct75]

Use a piece of Romex wire to run in the wall cavity from the panel into the back of a surface mounted box. Use NM clamps where the Romex exits the panel and where it enters the back of the surface mounted box. At the box change to conduit and THHN wire.

I'd prefer to avoid any wire splices if possible, I may be getting an EV and if so I'd have a connection that pulls 60 amps for hours at a time.

Try one of these to come out of the panel and into the back of the box
You can adjust it with different lengths of conduit *******

It's called a "bushed elbow"

I guess I'm looking for a box large enough to handle THHN for 5+ circuits and will need a semi-large conduit feeding the rear of the box. Does screwing a board across the stud and mounting the conduit box to that make sense? Is there a "double row" 4x4 box that would allow wire to come in from behind the wall and exit on the surface through conduit?

Whats the HP rating on the compressor's motor as listed on the nameplate label?

3.7 HP and it will be directly wired.

 

[alfredeneuman]

How about a wireway instead of a box?

They're available in all sorts of sizes (4X4, 6X6, etc.) and lengths of 1 foot-10 feet (You'll need the end caps too)

 

[mct75]

That's not a bad idea! However, the more I look at it, the more it makes sense to just get a subpanel and surface-mount that. The panels have a bazillion knockouts all over and I wouldn't have to fool with getting a dozen conductors through the drywall. I'll still have to run 4 wires for the panel through an elbow or something but that's a one-and-done.

 

[Bert_]

You could use a 4" or 4 11/16 square box and stack an extension ring on it. The rear box would be behind the drywall and the extension would be on the surface. Run conduit into the side of the back box and run conduit on surface into the extension.

I've actually done that a similar thing on a job. Rough in was all conduit and once sheet rock was up I added 4x4 extension rings above the drop ceiling and ran flex to lights and stuff. The drop ceiling was like a cloud, meaning it did not go all the way to the walls so the ceiling above was sheet rocked and finished.

 

[LXCam]

Count me in with using the telephone 90 like Alfred posted and a LB. makes for a very clean installation.

 

[Norcal]

I have run flex/greenfield to a single gang cut in box, then used one of these to transition to exposed EMT. https://www.homedepot.com/p/4-in-21...ion-Ring-Case-of-25-531511234UB-25R/206465546

Also have used a single gang Bell weatherproof extension to do the same thing, in one application had trouble finding one with 3/4" hubs.

 

[homebuilt burner]

I flush mounted my breaker panel also. I added a 6x6 pulling box that sits proud of the finished wall that is for future surface wiring needs.

You could cut a hole in the dry wall and add something like that. That would get you out of the wall and into something that you could attach conduit to.

 

[Jamie V]

This question is right up my alley. I flush mounted my 150A panel in my pole barn wall and did all surface mounted EMT. I made a box out of 18ga Sheet Metal that mounted 1/2 in the wall and 1/2 out of the wall. Behind the wall I ran a short piece of large EMT to connect the panel to the box, then all the surface mounted EMT could stab into the box outside the wall.

 

[alfredeneuman]

How would the OP finish his drywall around a box like that?

 

[mct75]

Yeah, conduit + THHN on the surface is easy and NM behind the walls/going to the attic is easy but I don't see a lot of people mixing the two.

I don't mind conduit (I think it looks cool) but I'm still scratching my head on a way to get 10+ conductors up to the surface of the wall, or plopping a subpanel on top of the wall without it looking like ****.

 

[Bert_]

How would the OP finish his drywall around a box like that?

Mud around it and paint. Or you could even just caulk it if you keep the hole close to the right size.

This question is right up my alley. I flush mounted my 150A panel in my pole barn wall and did all surface mounted EMT. I made a box out of 18ga Sheet Metal that mounted 1/2 in the wall and 1/2 out of the wall. Behind the wall I ran a short piece of large EMT to connect the panel to the box, then all the surface mounted EMT could stab into the box outside the wall.

That is a really nice job on that box but I wonder why not just surface mount the panel?

 

[mct75]

Alright, I ended up adding a sub panel half-inset into the drywall in the same stud bay as the main. This way conduit on the surface of the drywall can go right into the box. It's using a 60A feed breaker and 2AWG copper wire, run in an offset ****** and a LB conduit body. I still need to add white tape to the neutral wire and place a removable panel on the slot between the two panels but otherwise it's done.

Any thoughts on my implementation?

https://i.imgur.com/rL0KjcS.jpg

https://i.imgur.com/4SZmUGH.jpg

https://i.imgur.com/DkPTBy7.jpg

https://i.imgur.com/CwKuuhb.jpg

https://i.imgur.com/DXeinQt.jpg

 

[traumadoc2b]

It looks OK, except I don't think you can legally conceal an accessible conduit body (your LB)

 

[sparky 1971]

It looks OK, except I don't think you can legally conceal an accessible conduit body (your LB)

That's correct, but I doubt if anyone cares after 6-1/2 years. I'm having a hard time believing nobody gave him an internet beating when he installed it in July of 2018. I didn't come along until the following October.

 

[Bert_]

That's correct, but I doubt if anyone cares after 6-1/2 years. I'm having a hard time believing nobody gave him an internet beating when he installed it in July of 2018. I didn't come along until the following October.

I thought that too, plus that offset ****** screwed into an lb. Oh the horror

I'll punish myself later.

 

[mm08822]

That's correct, but I doubt if anyone cares after 6-1/2 years. I'm having a hard time believing nobody gave him an internet beating when he installed it in July of 2018. I didn't come along until the following October.

Peak vacation period.......who was covering that week?

 

[mm08822]

I thought that too, plus that offset ****** screwed into an lb. Oh the horror

I'll punish myself later.

Oh worse than that.......

• unmarked neutral
• Emt connector used as chase ******

 

[dave*99]

I thought is was bad luck to speak ill of the dead (thread). But I'll bite.
Landing the neutral as shown is odd. It covers a bunch of the terminals for the branch neutrals.