I'm sure some of you savvy electrical guys are going to snicker at the question, but I can live with that.

The situation: I have a four wire 220 outlet in my garage that I use for my powder coating oven. I just upgraded to a 220 Tig welder with the standard three-prong 220 plug that most welders use. Can I make an adapter that is basically a short extension cord with a female three-prong plug and a male four-prong plug? If so, how do I wire it. I am not sure what to do with that damn 'nuetral' wire on the four wire 220 circuit. Or, is the best solution to continue the circuit I already have running to the four-prong outlet up to a three-prong outlet and, if so, how do I do that?

Thanks. I hate to ask such a basic question here but I asked three guys at Home Depot and got three different answers. Not exactly a confidence-building experience.

 

If you don't get an answer pm me and I'll ask my electrician friends.

 

Don't bother with Home Depot, they know wood and paint, not much else.

We had this problem at one of our last races with our generator and welder, and my old chief rewired it, plus he hard wired all our equipment in the shop. I'll try and track him down and see what he says (don't hold out for an answer though, he just got married and I doubt he'll be answering the phone for a month).

If you don't want to wire one yourself, I know we have a 3 - 4 adapter for our plasma cutter, you could search for something like that.

Sorry I can't be of any better help.

 

Wire up your 2 120v hot legs and your neutral wire.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TurboLSVtecTeg &raquo;</TD></TR><TR><TD CLASS="quote">Wire up your 2 120v hot legs and your neutral wire.</TD></TR></TABLE>

So, you're saying to lose the ground out of the four-wire circuit?

 

yes..

 

Check out my post :

http://www.hobartwelders.com/m...26086

 

Thank you, that looks like what I need.

 

If I remember, you wire the two hots and the ground and leave the neutral alone

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by TurboLSVtecTeg &raquo;</TD></TR><TR><TD CLASS="quote">Wire up your 2 120v hot legs and your neutral wire.</TD></TR></TABLE>

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by paulzy &raquo;</TD></TR><TR><TD CLASS="quote">If I remember, you wire the two hots and the ground and leave the neutral alone</TD></TR></TABLE>

This is exactly why I am unsure of how to wire it. . . .

 

The neutral is not needed.

 

2 hots and the ground is all you need

 

Is this a dryer style plug?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by essex &raquo;</TD></TR><TR><TD CLASS="quote">Is this a dryer style plug?</TD></TR></TABLE>

I am using it for my powder coating oven. It is the round locking style, not the usual dryer plug with the triangle holes.

 

Four wire usually means 3 phase

 

No, not usually. Anything is only usually when that is what someone is used to working on or with.

There is 4 wire single phase: 2 hot legs, 1 neurtal, 1 ground
4 wire three phase: 3 hot legs, 1 ground.

 

Iv never personally seen 3 phases in a residential box but I know some people have it. Look at your fuse box and see how many power leads are coming in, either 2 or 3. One way or another you will need to wire 2 powers and 1 ground. I use all the same 4-prong 30amp (intended for 3 phase equipment) electrical connectors in the shop for 3 phase as well as 2 phase (or whatever you'd like to call it). 1 of the power wires from the fuse box is simply not used for the 2 phase machines. hth

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by KFMRC &raquo;</TD></TR><TR><TD CLASS="quote">Four wire usually means 3 phase</TD></TR></TABLE>

No - its residential. Houses often use four-wire plugs for driers, ovens, etc.

 

check the outlet with a tester for which legs are hot and which are ground and use only those 3

 

In a residence that has 220 coming in, you will usually find that the Neutral and the Ground are bonded together in the panel. You can check this with any AC meter.

You can also check for voltage between the neutral & ground, you should have a big ZERO. And since they are bonded at the panel, you could even bond them at the outlet end. The reason they are run split is allow for the load. Once you verify ZERO between the neutral & ground, you can check continuity with most DMM. You'll most likely find they are the same.

As far as the 4 wire to 3 wire, as long as you have both 120 legs and the neutral/ground in between, you are fine.

 

your four wire recepticle consists of 2 120 volt hot legs 1 neutral for lighting/timers and 1 ground... if your panel is bonded it is okay to use neutral as a ground. if your panel is not bonded DO NOT use neutral as a ground. what i mean by bonded is if you take the cover off you electrical panel you'll see a neutral bar on the left and the ground bar on the right and at either the top or the bottom of the pannel you might see a 4 or 8 ga bracket connecting the two bars together. if you see this the panel is bonded. you could also get a 4 X4 junction box and install it prior to your 4 wire setup and pull your 3 wire setup out of the side to your new setup. if you have any questions pm me.

 

Got it done. Ran the ground and neutral together with a jumper at the plug and it works great. Now I can make ugly Tig welds in the comfort of my own home.

Thanks to all that helped.