Advice for changing welder/compressor outlets and wiring

[vwtrey]

I'll be the first to admit, I'm not smart when it comes to electrical. I can figure out car wiring, swap out light fixtures in the house, even move a 110 outlet, but all of that expertise is my limit! Sarcasm, I'm an electrical idiot.

My new garage has two 220ish outlets that need moved and I need to change the plugs. I should say, I need to have someone do it but I don't want to go in blind. One outlet is a Nema 14-50 and the other is a Nema 10-50. One has a 30 amp breaker and the other is a 40 amp. I can assume which one is which, but I won't do that. Anywhos, my welders and compressor use Nema 6-50, so I need to change these two along with moving them.

So here's what I think is the best solution, and I'm hoping you guys can tell me where I'm wrong. I have plenty of leftover romex 6/2 from when I had the outlets added in my current garage. Would it be easiest to buy two Nema 6-50 receptacles, pull out the old wiring, and rewire with the new leftover romex? That would avoid an unneeded junction in a box somewhere, I already have the wiring, and I'm just buying two receptacles? Is there anything I'm not thinking about? I'd like the compressor run to the back of the shop, so I'll estimate 40', and the welders on the wall halfway down, so let's say 40' for that too.

What are your thoughts?

 

[Firebrick43]

I'll be the first to admit, I'm not smart when it comes to electrical. I can figure out car wiring, swap out light fixtures in the house, even move a 110 outlet, but all of that expertise is my limit! Sarcasm, I'm an electrical idiot.

My new garage has two 220ish outlets that need moved and I need to change the plugs. I should say, I need to have someone do it but I don't want to go in blind. One outlet is a Nema 14-50 and the other is a Nema 10-50. One has a 30 amp breaker and the other is a 40 amp. I can assume which one is which, but I won't do that. Anywhos, my welders and compressor use Nema 6-50, so I need to change these two along with moving them.

So here's what I think is the best solution, and I'm hoping you guys can tell me where I'm wrong. I have plenty of leftover romex 6/2 from when I had the outlets added in my current garage. Would it be easiest to buy two Nema 6-50 receptacles, pull out the old wiring, and rewire with the new leftover romex? That would avoid an unneeded junction in a box somewhere, I already have the wiring, and I'm just buying two receptacles? Is there anything I'm not thinking about? I'd like the compressor run to the back of the shop, so I'll estimate 40', and the welders on the wall halfway down, so let's say 40' for that too.

What are your thoughts?

what size of air compressor are you thinking about, very important piece of information.

 

[vwtrey]

what size of air compressor are you thinking about, very important piece of information.

I have an 80 gal Kobalt, rated at 22 amps

 

[Firebrick43]

Neither of those receptacles are rated for that HP. You won't find normal nema receptacles rated for that power.

You need to either hard wire with a disconnect or use a pin/sleeve type receptacle system, which are very expensive but typically do not allow disconnection/connection while the receptacle is live(has a disconnect built in)

 

[AntonLargiader]

How has that compressor been connected in the past?

EDIT: Never mind, I see you mentioned that they were connected with 6-50. Is there a HP listed on the compressor motor? What size breakers were they on before? Here's a related thread that puts some perspective on the HP rating thing:

what kind of 220 compressor can i plug into 6-50 outlet?

I have no clue what I'm doing and came across this site from google searching. I'm renting a family shop and want an air compressor for auto stuff. They showed me 220 outlets so at first I assumed just to go shopping for any unit but now I see thats not the case because of the amps, breakers...

www.garagejournal.com

 

[vwtrey]

How has that compressor been connected in the past?

It's on a nema 6-50. Has been for about 6 years. I had a licensed electrician do the work on it. I didn't realize nema had horsepower ratings.

This compressor is rated at 3.7hp

 

[vwtrey]

How has that compressor been connected in the past?

EDIT: Never mind, I see you mentioned that they were connected with 6-50. Is there a HP listed on the compressor motor? What size breakers were they on before? Here's a related thread that puts some perspective on the HP rating thing:

what kind of 220 compressor can i plug into 6-50 outlet?

I have no clue what I'm doing and came across this site from google searching. I'm renting a family shop and want an air compressor for auto stuff. They showed me 220 outlets so at first I assumed just to go shopping for any unit but now I see thats not the case because of the amps, breakers...

www.garagejournal.com

The motor is 3.7hp. It's on a 40 amp breaker now, but apparently that isn't the only consideration here. I didn't know that.

It's not a huge deal for the new shop. I can hardwire it to the 30amp breaker with a disconnect in between. But I need to consider startup amps.

If I wire the welders through a plug to the 40 amp, what do I need to consider. One welder has a max amp draw of 20amp, the other is 28amp.

This has been eye opening.

 

[Firebrick43]

A volt meter and shutting off one set of breakers can tell you which is which.

I personally would make your outlets 14-50 as its the standard that many jurisdictions are heading to, as it has a ground and a neutral. You can also get 120v out of the outlet as well. It should be the 40 amp circuit but if its not and your putting wire in anyways, make it so. Most of your level 2 EV chargers are standardized on a 14-50 with 40 amp breaker so it will some what future proof you.

Amp draw of the welders (as long as you don't exceed the breaker) is insignificant. The breaker is there to mainly protect the wiring/receptacle not the appliance.

 

[PCustoms]

The motor is 3.7hp. It's on a 40 amp breaker now, but apparently that isn't the only consideration here. I didn't know that.

What is on the actual motor tag, NOT the plastic shroud?

Bet it's 2hp max, the 3.7 sounds like marketing HP.

 

[Firebrick43]

What is on the actual motor tag, NOT the plastic shroud?

Bet it's 2hp max, the 3.7 sounds like marketing HP.

22 amps would be somewhere around 3.7 hp. Its a compressor duty motor more than likely. 17 FLA is 3 hp

 

[vwtrey]

What is on the actual motor tag, NOT the plastic shroud?

Bet it's 2hp max, the 3.7 sounds like marketing HP.

It’s on the motor tag.