220V install questions

[JCS1994]

Hey guys I just bought a welder that requires 220V input and it requires a 30A breaker and I am getting ready to get a 220V outlet installed in my garage but am planning on doing it myself but had some questions. So i have a recessed circuit breaker in the garage and an open attic that I can run the wire through to get to the opposite wall as the breaker. Do I need a specific kind of box to mount the outlet in the drywall? And to be up to code do I have to anchor the wire down to the garage’s ceiling joists or anything up in the attic? Thanks in advance, Jeremy

 

[pattenp]

Use a 4" steel box with a single gang mud ring. The cable across the ceiling joist need to be secured every 4'.

 

[teamextreme]

Do I need a specific kind of box to mount the outlet in the drywall?

I understood his description to mean the wall is already drywalled, in which case the 4 square box and mud-ring is not appropriate. You need an "old work" box, of which there are many flavors. The selection will depend mostly on what type of wiring method you are using, which you didn't mention. Romex? EMT? PVC? Some type of flex conduit? Bus duct?

 

[Wrench97]

Old work boxes and 30 amp 220 plugs may not go well if plugged and unplugged often, he may want to bite the bullet and cut a hole or surface mount a box on top of a stud.

 

[JCS1994]

I would be using 6/2 or 8/2 Romex. And I have been seeing “old work low voltage boxes” and I am under the impression those are not for use with 220V. Is that correct or could I use one of those boxes and mount it in the drywall? I figure I will have to cut a hole in the drywall for a box regardless but I would like to not have to cut excess out to access the nails to nail one to a stud.

 

[wyliesdiesels]

I would be using 6/2 or 8/2 Romex. And I have been seeing “old work low voltage boxes” and I am under the impression those are not for use with 220V. Is that correct or could I use one of those boxes and mount it in the drywall? I figure I will have to cut a hole in the drywall for a box regardless but I would like to not have to cut excess out to access the nails to nail one to a stud.

Theres old work boxes for electrical as well but they will be floppy...

 

[JCS1994]

I think even though it is extremely unsightly, I am going to just run a surface mount 650R outlet. There is a 120V outlet about 4’ off the ground right where I’d like to put my 220V. Is it still within code to have the 220 outlet directly below that around 2’ off the ground so I can just use the same hole at the top of the wall in the attic or is that a violation of some sort? I would like to drill as few of holes as possible but if I have to drill 1 extra it will not be the end of the world.

 

[pattenp]

No problem that I can think of.

 

[teamextreme]

Make sure you use a deep 4" square box (2-1/8" deep). A 50A outlet will not fit properly in a standard 1.5" deep box (even if you may be able to cram it in there).