220v Wiring

algranger · Apr 27, 2011

So i bought a millermatic mig machine yesterday. The welder has a 6-50p plug on it and my house has a 10-30r receptacle so I want to make an extension cord for it that will have a 6-50r on one end and 10-30p on the other end. I need help figuring out where to connect the wires. I've been trying to read up on it for hours and its giving me a headache. Maybe someone can shed some light.

Toyotanut · Apr 27, 2011

when you take things apart cord caps the gold screw goes to black, silver screw to white and green to ground/bare.

Bill · Apr 27, 2011

Toyotanut said:
when you take things apart cord caps the gold screw goes to black, silver screw to white and green to ground/bare.

220 = black and red for hot then white or green for the ground depending on what wire you use

Toyotanut · Apr 30, 2011

Bill said:
220 = black and red for hot then white or green for the ground depending on what wire you use

True, but depending on what he's got for SO cord there won't be a red in there, unless it's 4 wire. So it will probably be black, white and green.

Color really doesn't matter as long as both ends are connected the same. Only colors that matter are white, gray, green and orange.

Murkman · May 1, 2011

Toyotanut said:
Only colors that matter are white, gray, green and orange.

Elaborate on that thought for us please.

Toyotanut · May 1, 2011

Murkman said:
Elaborate on that thought for us please.

NEC code 200.6 specifies white or gray as identifiers

NEC 110.15 specifies orange as an identifier

NEC 250.119 specifies green as an identifier.

Other than that as long as you know what you have going on at both ends you can use what ever color you want. Black, red, blue has just become common practice to use for 120v/220v identification, just like brown, orange, yellow has become for 277v/480v identification.

Murkman · May 1, 2011

Toyotanut said:
NEC code 200.6 specifies white or gray as identifiers

NEC 110.15 specifies orange as an identifier

NEC 250.119 specifies green as an identifier.

Other than that as long as you know what you have going on at both ends you can use what ever color you want. Black, red, blue has just become common practice to use for 120v/220v identification, just like brown, orange, yellow has become for 277v/480v identification.

Go back and see what happens when you use So or sjo or sow type cable. Thats what you were talking about when you started quoting colors.

84Toyota4x4 · May 1, 2011

As its been stated, the electricity doesnt care what color wire its in, just make sure both ends of the extension cord are wired up correctly. The only "issue" most people will argue is that the 10-30R has no true "ground" since it uses a neutral. My reply to that is simply that if the outlet is on its own true dedicated circuit as it should be, the neutral wire should have zero voltage potential because its bonded to ground back at the panel. So unless the appliance running off the plug is using only 120 volts and not the full 240, the neutral wire for all intents and purposes would be a ground.

That said, on the 10-30R you have on the wall, the "L" shaped pin will be neutral, the two blades are hots.

On the 6-50P on the welder, the two blades are hot, the "round" "D" shaped pin is ground.

Thus, get yourself some 3 conductor wire as mentioned and connect the 3 wires on each end to the corresponding pins. Hot to hot (doesnt matter which one, they each carry 110 volts), and just make sure the ground pin connects to the neutral pin.

Hope that helps.

~T.J.

Murkman · May 1, 2011

My thoughts as to the topic at hand is that the OP has provided no info other than he has a welder with a 6-50p on it and is looking for advise to hook it up to a 10-30r. The OP admits he does not know what to do and even after much reading he still has no clue.

Anyone see a problem with this. Is he going to do this conversion to his property or is it a rental? Does he have family that resides with him. Does he realize the danger he is about to undertake and expose his family and property to, to accomplish this foolish idea he has.

Yet he has recieved no real info from anyone who has taken the time to encourage him on.

My advise to the OP is to call a qualified electrical contractor to have the work done. Insist that the work is done to code and prove that the work was infact done to code by posting an Electrical work permit and have the work inspected.

Now start telling me about the code. Go back and read the opening paragraph to the NEC.

pokey · May 1, 2011

cool code thread :cheer:

Murk give me a call I have a job for you.

Binder · May 2, 2011

The OP isn't trying to change anything about the structure he's trying to adapt a 50 amp device and plug it into a 30 amp outlet. If it's in fact a 30 amp circuit it won't work out so well. :booo:

84Toyota4x4 · May 4, 2011

Yet he has recieved no real info from anyone who has taken the time to encourage him on.

While I completely agree if someone doesnt know at all what theyre doing and doesnt feel comfortable doing it they should consult a professional, I did in fact attempt to explain the problem with it before I told him how to make it work. Neutral does not equal ground, however, it will work in this case because of the particular situation. This isnt the first guy to wire up a 220 welder to a dryer outlet by any means. That said, OP, if you arent 100% clear with what you are doing, dont try and make it work. Double check and verify provided information. Its not worth your life or those around you when something goes wrong. Its also not my fault if there is an issue with the wiring, you make a mistake, whatever else and something goes wrong, Im just telling you how Ive done it and its worked for me. Im no professional though.

The OP isn't trying to change anything about the structure he's trying to adapt a 50 amp device and plug it into a 30 amp outlet. If it's in fact a 30 amp circuit it won't work out so well. :booo:

My Hobart 187 has a 50 amp plug on it like most 220 welders in its class (his Miller as well Im assuming), but its only rated at 20.5 amps at load, 230 VAC. Even if you assume a low voltage of 200, thats still safely under the 30 amp breaker for the wall outlet. Ive ran mine off 30 amp dryer outlets a number of times with no issues.

Granted, his could be more, Im just saying that just because it has a 50 amp plug doesnt mean it pulls near 50 amps - especially seems to be true with welders of that size/class. To the OP, which model Miller is it? Is its rated load less than 30 amps?

~T.J.

Murkman · May 4, 2011

The NEC is a minimum standard. Nothing that has been suggested to the OP meets those minimums.

The owner of this board has taken offense with people selling guns if they do not post the serial number with their add. He is worried about his liability. Maybe the owner of this board should have the same concern with people who tell others how to do something against a published code.

zig80toy · May 4, 2011

and just remember, the smoke comes prepackaged.

ChrisStewart · May 4, 2011

Murkman said:
The NEC is a minimum standard. Nothing that has been suggested to the OP meets those minimums.

The owner of this board has taken offense with people selling guns if they do not post the serial number with their add. He is worried about his liability. Maybe the owner of this board should have the same concern with people who tell others how to do something against a published code.

I had a big post written but I will condense it, if you know the NEC and WAC standards, let the OP know, (I mean if you have this wealth of knowledge by all means share.) instead of getting your vag all wadded up because crash wants us to post serial numbers for guns on his sight. FYI homeowners don't have to follow NEC or WAC unless they are getting it inspected, but I am sure you already knew that.

ChrisStewart · May 4, 2011

algranger said:
So i bought a millermatic mig machine yesterday. The welder has a 6-50p plug on it and my house has a 10-30r receptacle so I want to make an extension cord for it that will have a 6-50r on one end and 10-30p on the other end. I need help figuring out where to connect the wires. I've been trying to read up on it for hours and its giving me a headache. Maybe someone can shed some light.

Alex for correct wire size we need to know what the Full load amps of your welder are. my miller 180 is 20.9 and I have a 50 amp plug on my machine and wall. I used 10/3 wire, to compensate for voltage drop, if you are going to run a super long extension cord, run even a thicker wire. (Disclamier not an O1 electrician, only O6A certified, and training hours for O7) :flipoff:

thursday · May 5, 2011

You won't be able to run a ground to your welder, thats the main problem. Can you make it work? Yes, but it would be a lot better if you had a newer dryer outlet that had a ground in the plug. Your welder will want two "hots" or "legs" from your panel, A phase and B phase, it also needs a ground in case of short circuit it will trip the breaker. Your welder does not utilize a neutral, these are for 120 volt loads ONLY, and some welders may use them but the plug you mentioned is a single phase 240 volt plug with 3 pins, two hots and a ground.

Making it work will not be WAC or Code compliant, and could be unsafe since there is no reference to your panels ground. 10/3 wire is only rated to 30 amps as well, you will need 8 gauge wire to run 50 amps.

EDIT: don't get confused when I said single phase, single phase 240 volts utilizes two phases from your panel but is still called single phase.

Murkman · May 6, 2011

ChrisStewart said:
FYI homeowners don't have to follow NEC or WAC unless they are getting it inspected, but I am sure you already knew that.

How can you be so knowledgeable yet so wrong. Any alteration, addition, modification must be permitted, done to code and inspected.

Been an 01 for 25+years. Have held an A-man card although I let it expire as I no longer needed it. Member of the IAEE for lots of those years.

Personally if I were to give electrical advise on a forum to someone it would be via a pm. That way a posser would not expose themselves for all to see, for their knowledge base or lack there of.

Jaydog · May 6, 2011

Holy cow batman, it sounds like he just wants an extension cord that plugs into his drier plug at one end and his welder at the other, it's pretty simple, I have one and didn't get it inspected :haha::haha:

It will work good as long as you don't have a heavy load, then you'll be blowing the breaker :redneck:

Murkman · May 6, 2011

Jaydog said:
Holy cow batman, it sounds like he just wants an extension cord that plugs into his drier plug at one end and his welder at the other, it's pretty simple, I have one and didn't get it inspected :haha::haha:

It will work good as long as you don't have a heavy load, then you'll be blowing the breaker :redneck:

True and as to whether it meets code seems to be the question. Also the OP states he has no knowledge as to how to do this. Look over the thread. Has he recieved any info that would accomplish this for him?

As for your breaker idea. True in some cases, false when the self acclaimed electrician uses to small a wire. Then the wire becomes a fuse when it overheats and catchs nearby combustibles on fire. Or worst yet someone inadvertinly comes in contact with it.