Wiring Question for a compressor using a Welding Outlet (I think)

[hazexban]

Sorry for this question but I am hoping someone can help.

I bought a house and in the garage the previous homeowner had a welder and a 60 gallon compressor. He had wired up the outlet in this picture, I believe it is a 50 amp 250 volt plug. He used this plug for both his welder and compressor (not at the same time).

Now I bought a used 220v air compressor and want to connect it to this outlet.

This plug seems to be what I need: http://www.lowes.com/pd_423570-4346...&currentURL=?Ntt=plug&page=1&facetInfo=3-wire

Is there anything special I should know about in wiring this plug to the compressor? The electrical motor does have its own reset button on it for overload protection so I am not really worried about that, plus I got this compressor dirt cheap but I digress.

I have been reading all sorts of things about welders having the outlet wired differently for how they work but it's kind of over my head.

Or after all of this am I crazy for doing this? I am only wanting to utilize this outlet because I know the previous owner used it for his compressor too.

Thanks in advance!

Pete

 

[wyliesdiesels]

If it is 50a, then its a NEMA 10-50R. There should be a marking somewher eon the receptacle.

What is the HP rating of the compressor, the actual rating from the motor nameplate?

 

[hazexban]

The motor only says 2.3 hp, 230v, 60hZ, 3450 rpm, 18.4 amps, thermally protected..
Thanks!

 

[toyotadriver]

What gauge wire to the outlet?

99.999% chance it'll work fine. Find out what gauge wire you have and you'll know for certain.

In theory 12ga wire would work. However, I'd wire a typical 240 volt air compressor with 10ga wire or larger.

 

[JoeFin]

Looks to be a standard 240/3 wire 50 amp receptacle found behind most Electric Ranges

 

[wyliesdiesels]

The motor only says 2.3 hp, 230v, 60hZ, 3450 rpm, 18.4 amps, thermally protected..
Thanks!

If its 18.4a then technically, its gonna be just over 3hp. Standard receptacles arent rated for more than 3hp so technically, your just squeezing by.

The NEMA 10-50R is a non-grounding outlet, so u need to move the neutral wire in the panel from the neutral bar to the ground bar, IF U HAVE A 4-wire fed subpanel. And technically code wise, the wire should be green not white, so this wont be to code.

What gauge wire to the outlet?

99.999% chance it'll work fine. Find out what gauge wire you have and you'll know for certain.

In theory 12ga wire would work. However, I'd wire a typical 240 volt air compressor with 10ga wire or larger.

12ga THHN that is. Typical? Whats typical. Wire gauge is based on FLC which is based on motor HP and every compressor has a different HP rating....

Looks to be a standard 240/3 wire 50 amp receptacle found behind most Electric Ranges

which is not grounded....

 

[sberry]

If this box is connected with a cable it should be grounded also. The yoke on that type of recept is not bonded. I am guilty of using these on occasion, I put a jumper in for the bond but a good solution would be to replace it with a 6-50-R and then it would serve a welding machine also.

 

[hazexban]

Thanks everyone, with your advice I was able to get the compressor up and running!

 

[460Rustang]

Pictures,.....