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Wiring for Compressor

Marty57

PATRON
Nipomo, Ca
I bought a new compressor, Ingersoll Rand 60g 5hp single stage.

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Working on hooking it up and wiring it. I would like to plug it into the same circuit I used for previous compressor. I only have one 230V outlet in my shop (4 prong from dryer, moved dryer outlet from house to shop). For existing compressor, Arch Welder and Tig welder; I have a three prong to four prong extension cord with a box on the end and it works fine, I taped off the white wire from the four prong cord inside the box.

I would like to use a 35-6 dryer cord to wire the compressor; will that work? The control box on the compressor has black, white, and green terminals. Can I hook up the white to white, black to black, and green to green and tape off the red terminal from the 35-6 cord inside the control box for the compressor? Or, should I wire the compressor with the same three prong as the Tig and Arch welders and use the adapter cord I have? Web, you helped me when I made the extension cord and it has worked great, thanks. Now, how to wire the compressor?

Here's the adapter cord I have been using:

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Here's the cord I would like to connect to the compressor to match the wall outlet:

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And last, here is the control box on the compressor:

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Can I use the new cord with this compressor by just taping off the red wire?

Thanks,
Marty

added one more picture, from the motor:

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How big is the circuit and what is the compressor rated at, 30A? As long as the compressor doesn't overtax the circuit, no sweat. You don't need the 4th leg. It's just a neutral, which allows you to safely/correctly get 120v out of a 240. All you need for 240 single is the two hots and the ground. It really doesn't matter which route you choose, you're effectively doing the same thing. From a simplicity standpoint, if the comp. already fits the adapter cord I'd just go ahead and use it.
 
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No wiring on new compressor yet, 4 prong cord is easy to get already made up. Circuit is connected to two 30A breakers ganged together. Compressor is rated at 24.4A so I think the circuit should handle it ok. Thanks for the advice.
Marty
 
Depends how the ext cord is wired. Standard is red and black for the two hot phases. Green Ground. White neutral which you won't need.

The motor is wired black and white for the two hots and green ground. No neutral.

So you would go motor black to cord black. Motor white to cord red. Green to green.
 
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Not sure a dryer cable is big enough. Do you know what gauge it is?

Your two hot legs are going to be the flat blades on the plug. Ring those out to see what colors they are. Then either one can hook to the black wire on the compressor box and the other to the white wire. You'll have to figure out which of the round blades has continuity all the way back to the wall box. That blade will connect to the green at the compressor box.

Not complicated but the color codes may be mixed here, so check everything with a volt/ohmmeter.

Web
 
The extension cord I made up has the white taped off. So, I’ll use red on dryer cord to white on motor and black to black, green ground; white on dryer cord not used, sound righ? Size of dryer cord I am looking at is same size as motor to control box on compressor. Size is 8/2 on dryer cord, rated for 50A. Sound right so far?
Thanks,
Marty
 
Verify before using a color!

If the dryer cord is the same gauge as the wire on the compressor you should be good.

Web
 
Manufacturer should be SHOT for not at least putting Black or better yet Red tape on that white wire if it's indeed wired for 220/240 volts!

Use the cord, Black to Black.. Red to the compressor White, Green to Green, Tape the cords White off, or better yet cap with a marret.
 
No, it will not work as you describe. The flat blades on your cord are the hot blades and are connected to the red and black wires. The white and green wires are connected to the round spades and are your neutral and ground respectively. Check your PM’s and find yourself a qualified electrician
 
No need for a plug at all, and I'm surprised no one else mentioned that, any qualified Sparky can just hardwire it in, unless you're planning on moving it around? I did my own, same size/HP, right from the shop's main panel, so didn't need to figure out what cord color went in which blade, etc. It was obvious the two hots went to the 240 breaker, and the bare copper went to the ground. Just three wires to disconnect when you wear it out and buy another, your plugs just complicate things it sounds like!
 
Just use an ohm meter to trace the legs of the cord before you make any connections, that takes the guesswork out of it. The "L" shaped pin SHOULD be the white, and that's the neutral you won't be using. The two flat pins are hot (120v each relative to ground/neut. -- 240v between them) and the round is ground.
 
No need for a plug at all, and I'm surprised no one else mentioned that, any qualified Sparky can just hardwire it in, unless you're planning on moving it around? I did my own, same size/HP, right from the shop's main panel, so didn't need to figure out what cord color went in which blade, etc. It was obvious the two hots went to the 240 breaker, and the bare copper went to the ground. Just three wires to disconnect when you wear it out and buy another, your plugs just complicate things it sounds like!

Problem with wiring it direct is first, I don't have a panel in the garage/shop; the service panel is on the other end of the house and outside. Second, although I'm not moving it around, I do need to use that outlet when I need to use the Tig or Arch welder. I need to unplug compressor so I can run the Tig on the circuit. With the service to the garage/shop, if I were to put in a sub panel and hardwire the compressor and have an outlet for the Tig or Arch, I would get dinged by code. I don't think I have enough amps or sized cable to run both the compressor and Tig at same time. Even though i don't plan on running both simultaneously, if the set up would allow that to happen the wire needs to be larger. I had that in another shop and had to change it when I moved because it was out of code. I hope I'm being clear.

I'm trying to avoid spending more than the cost of the compressor to run a dedicated circuit to the shop. Is it against code to have this type of compressor on a cord? Would it be better to change the outlet in the wall to three prong NEMA 60 (matching the Tig and Arch welder)? Can that be done? Maybe eliminating the extra wire at the outlet and back in the service panel? I'm not against bringing in an electrician but I want to have a good idea what's legal rather than someone trying to sell me a $1K rewire that I really don't need.

So, would I be better off changing the wall outlet to the Nema three prong that is currently on the end of my adapter/extension cord, and have all three devices with the same plug and eliminate the need for the cord/adapter completly? Or, just use a 4 prong plug on the compressor eliminating the extra natural?

Thanks,
Marty

Thanks for the education so far; getting closer to a solution I think.
 
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