Wire size for welder

[frankd]

I know there are alot of factors to consider for this but I'm in the process of rewiring my garage and wanted to get everything pre-wired for adding a welder in the future. I don't currently own a welder but would love to buy one and so while the walls are open I figure it's best to run the wiring now before the drywall goes up.
I know there are welders that will run off a regular 120v outlet but was going to run a 240v line just to be on the safe side..
So my first question is regarding the number of conductors... From what i've been seeing, welders only need 2 wires plus ground. Is that correct? Are there any welders that would need three wires (2 hots and a neutral)?

Also, with regard to wire size, would going with 10 gauge be a pretty safe bet? I have some extra 6/3 wire laying around but think that would be serious overkill.. and plus its a pain to work with.

I don't plan on doing any crazy welding. Probably will get a mig welder. Will do some auto/motorcycle work. Nothing crazy.

Any suggestions would be greatly appreciated.
Thanks!

 

[TractorJeff]

A smaller 240 volt outlet on 10 gauge wire with a 30 amp breaker would handle most homeowner size mig welders.
If the wall is open, then go 6-3 because a full 50 amps could be fed to it.
Before everyone poo-poos this statement, listen to my reasoning.
A 50 amp input stick welder can be put on 10 gauge wire with a 50 amp breaker because of Duty Cycle limitations.
A 50 amp outlet on 6-3 can accommodate a larger newer mig welder with a higher duty cycle if you so desire or a powder coat oven, then later in life when you sell, the garage could have an electric stove or kiln installed very easily (selling point)

 

[Norcal]

A smaller 240 volt outlet on 10 gauge wire with a 30 amp breaker would handle most homeowner size mig welders.
If the wall is open, then go 6-3 because a full 50 amps could be fed to it.
Before everyone poo-poos this statement, listen to my reasoning.
A 50 amp input stick welder can be put on 10 gauge wire with a 50 amp breaker because of Duty Cycle limitations.
A 50 amp outlet on 6-3 can accommodate a larger newer mig welder with a higher duty cycle if you so desire or a powder coat oven, then later in life when you sell, the garage could have an electric stove or kiln installed very easily (selling point)

There is no reason to use 6/3 NM for a welder unless you have excess cash to get rid of, 6/2 NM is fine.

 

[mike93lx]

Two wire, plus ground is all you need. Unless you are welding with some monster machine or the run is very long, 10 gauge is fine with a 50a breaker. 12 is fine too with most machines. I'd grab some stranded 10 thhn and use that.

 

[frankd]

Thanks for the replies. I'm running 6/3 wire to the sub-panel that I installed and will have plenty of extra to run to the welder receptacle. I just wasn't sure if that was overkill...or if that extra conductor was even needed as most welders I've seen dont need 2 hot wires.
6 gauge is just such a pain to work with..

 

[maxpat82]

I just wired my new garage...and I put a 8/3 wire to feed my planned welder outlet.
I'll be using this outlet with a stove outlet for now.

The plan is to have it ready for a welder, stove or futur car charger.

 

[mike93lx]

Thanks for the replies. I'm running 6/3 wire to the sub-panel that I installed and will have plenty of extra to run to the welder receptacle. I just wasn't sure if that was overkill...or if that extra conductor was even needed as most welders I've seen dont need 2 hot wires.
6 gauge is just such a pain to work with..

No. The third conductor is completely unnecessary. Save the wire or sell it.

Any 240v equipment needs two hots and a ground. The neutral is only needed if it has something running on 120v, like a fan, pump, or motor.

 

[strutaeng]

10/2 or 8/2 is what I would run.

Also consider running conduit without any wire. Buy the welder and figure what wire you need and run it.

 

[sberry]

Yes, if you plan to put an oven on it then its not a welder circuit anymore. I know a few hobby guys have 250 migs. Part of the attraction of new equipment anymore is the power demands. A 210 Synchro, was a 60A machine, now runs on 30A service. Small wire feeds take about 25 wide open.
The inverter sticks are great due to this. They are wonderful for residential 100A service,

 

[wyliesdiesels]

I just wired my new garage...and I put a 8/3 wire to feed my planned welder outlet.
I'll be using this outlet with a stove outlet for now.

The plan is to have it ready for a welder, stove or future car charger.

If the stove is gonna be on a 50a outlet then NM 8/3 is too small as its limited to 40a.

 

[frankd]

I just wired my new garage...and I put a 8/3 wire to feed my planned welder outlet.
I'll be using this outlet with a stove outlet for now.

Thanks for the replies. Good point on the car charger/stove. I think I'll go with 10/2 or 8/2. Not a long run at all so might be worth spending the extra money on 8/2

 

[sberry]

This can be the advantage of planning, some of the major runs are short, sometimes a guy can find drops, heavy wire doesn't cost much.

 

[sberry]

Many of the new welders allow 14. Old buzzers allowed 12 out to near 80 ft. There were substantial losses with this and performance dropped some. 10 at 50 ft or under makes for a circuit the operator cant tell the difference with.
I like 10/30 for the new ones, if a guy really needed to run a buzzer could change the breaker. It lets the little ones be all they can be.
If I am going to the trouble of getting a welder and wiring for it I like a dedicated circuit to it and never think I am going to run other stuff from it. Same with most equipment and to tell the truth I like to get about everything I can except for air comp and pressure washer on 120V,,,, yes,,,, I can wire my table saw for 240 but it works just the same on 120. The comps get their own circuit as does the washer which makes using the welder outlet for other stuff rather moot.
I don't have anything I really do that with.

 

[pbon]

Do building codes let you run 10/2 from a 50A breaker to a 50A rated outlet?

 

[mike93lx]

Do building codes let you run 10/2 from a 50A breaker to a 50A rated outlet?

You can actually run smaller if the outlet is for a welder only. Due to duty cycles

 

[wyliesdiesels]

Do building codes let you run 10/2 from a 50A breaker to a 50A rated outlet?

https://www.ecmweb.com/qampa/code-qa-45

 

[pbon]

I figured the code would be concerned about what the next guy plugs into the 50A circuit but it looks like it’s what you use the outlet for.

 

[brewchief]

If I had extra 6-3 wire laying there I would use it for the welder plug, yes it's overkill for most any hobby welder but I wouldn't go spend money to buy smaller wire, I would hook up all 4 wires in the panel and cap the neutral at the receptacle. No normal shop equipment needs the neutral but it's there if you need to swap to a 4 wire receptacle to plug a range in if your having a big party or chili cookoff.

 

[TractorJeff]

I just wired my new garage...and I put a 8/3 wire to feed my planned welder outlet.
I'll be using this outlet with a stove outlet for now.

The plan is to have it ready for a welder, stove or futur car charger.

This is the reasoning why I suggested 6/3!

 

[sberry]

If I wanted to run a stove and had the wire for it would put in a circuit, same for the welder. Only reason I would fug around with a dual use recept is if I was out of spaces, i it was a long run and had the 6 3 would likely put a panel on it.

 

[maxpat82]

This is the reasoning why I suggested 6/3!

I said to my electrician the plan to use for the outlet, and the 8/3 was is conclusion.

I mostly will never need a 50A receptacle (since any welder I'm looking at are 30A anyway, a stove is 40A and a car charger is 40A.)

I need to pull ~80ft of wire to get to the front of the garage (pannel is in the middle of the back wall) if ever a full 50A is needed I'll put it on the back wall.

I still have a pull string in my attic always ready to use and all my wall finishes can be unscrew and remove to access the wall, ceiling.

 

[Bert_]

If the stove is gonna be on a 50a outlet then NM 8/3 is too small as its limited to 40a.

Common and legal to wire a 40a circuit for a stove using #8 romex and 50a outlet.

I haven't run a 50A range circuit for a while. Most stoves will never pull over 30A, even with everything on.

 

[86turbodsl]

You should really determine WHAT welder you are going to run and how you plan to use it and THEN plan appropriately for that use case. If i had a welder with a high capacity or duty cycle and it was say GTAW, i would plan for more current capacity and larger gage than if i was just a hobby welder with a Lincoln tombstone tacking farm equipment. Generalizations are NOT ok in wiring.

 

[Toothaker]

Ok, then, let's be specific.

Lincoln Electric Easy MIG 180. The Operator's Manual says the Input Current is "20 Amps @ rated output" and it says "Duty Cycle 30%".

Using Table 630.11(A) in the NEC, if I'm reading it right, I multiply 20A by 0.55. This is 11A. So I can use an existing 25 foot long 12/3 Romex run in my garage, correct?

The Operator's Manual also says it needs a 40 A circuit breaker.

Please correct me if I'm wrong - based on the NEC, not your feelings or suppositions, such as "what happens if you buy a bigger welder?" That's not the question. I'm asking specifically about this one brand and model of welder.

 

[sberry]

I am not sure how Lincoln came to the conclusions and wording they did. I got a compact and will have to look at the manual,,, so this is from recall and not sure they didnt change it but it seems they said 8/40. The Hobarts call for 14/30 for this class of machine. The 14 is single circuit in pipe so a cable would be 12.

 

[sberry]

I have a 130T which I believe is the new 180 easy. Mine was about 1992 or so, before box store and number inflation but came with a 12 cord. It lists 8 in pipe and 40 with 10 ground. The 255 I have is 10/50, ,, go figure,, I think it has 8 cord.
I would guess done by diffetrnt engineer s.

 

[sberry]

Would you mind looking at the easy mig manual and see how they list it? I was at a factory deal and quized engineer at another company, some newer guys, probwbly genius on invereter designs but were not intimately familiar with wiring codes.

 

[sberry]

It seems I have asked but never found anyone to splain the Linc manual on that one. I have read a lot of manuals, never seen another one like it.

 

[Toothaker]

It seems I have asked but never found anyone to splain the Linc manual on that one. I have read a lot of manuals, never seen another one like it.

Agreed. The comparable Millermatic 211 does specify the minimum wire size (14) while the Lincoln Electric does not.

I genuinely want to do this right, and at the moment my walls are open so it will be easy to pull the right wire now. I've not selected a specific MIG welder yet, but my preference is in the 180 to 210 output amp size range. I've found the manuals for the other brands' models in this size range and they specify circuit wire size.

I don't think I can post the Operator's Manual here, but here is the link:
https://www.lincolnelectric.com/en-us/support/Pages/operator-manuals.aspx
search for Easy MIG 180

 

[Hot Rod Grampa]

I see this discussion all the time and am amazed that people would spend thousands of dollars on a fancy floor, have ten drill presses and 20 vices and yet refuse to spend a few dollars on adequate wire size for a welder. You have a 50 amp outlet on the wall fed by a garbage 14 wire. The logic escapes me. I bring my old buzz box over and plug it into a legal 50amp outlet and burn the garage down because the wire fried. How does that save money? I just can't grasp the sudden infatuation of saving twelve dollars. Sorry.

 

[Toothaker]

No need to apologize, Grampa. Did you read my post? The 12/3 is already in the wall, wired to the garage sub panel. I'm not just saving "$12", I'm also saving time and energy. I work full time, and Saturday is generally the only day I have to work in the garage. If possible I want to avoid pulling a new wire.

I have a plain concrete floor, an HF table top drill press that was given to me, and a $40 Chinese vice.

 

[sberry]

There are 2 things in the last couple of posts. First,, while it may ne a 50a outlet doesnt mean its a 50 circuit. If.... And no one really thinks this minimum is a great idra,, but this is a single circuit in pipe and if it is the limit is a 30 breaker, your buzzer way most likely to trip the breaker before the "fire".

 

[sberry]

Back to the easy,,, I notice that under amps it refers to "cable" and doesnt say wire. All the cable,, 20a is 12. Normally the listed breaker... In this case says fuse,, but it's the max ehen the minimum wire size is used. 12 thwn is 50a max but it would need to be less for a 12 cable. It takes a 10 cable to go on 50.
In reality you would have a tuff time burning the place down with a factory 50 end machine.

 

[sberry]

A buzzer comes 12 cord. I have ran them 10 cable till they were dam near cinders, barely warms the cable. The ratings were established when voltage was 220 and insulation has improved, they pull a couple less on dc too. A 1/8 AC lo hy used to be 43 or so, now under 40 @ 240.

 

[sberry]

These allowances are not a brain fart, they are pretty well thought thru for a long time. If this all would have been a problem they would have fixxed it in the last 70 yrs. If this is wired 12 cable which would be a min and a 30 it would run a buzzer turned up all it could be to trip a 30 before it would overheat the wire.
Just because these are code minimums doesnt mean they are inadequate. There is a margin of safety.
The rated on a buzzer is 225 out @ 20% at 48 in. Really a big difference in the real wprld with 120 output, 40 ish in.

 

[sberry]

A range, oven, charger circuit doesnt have a welder outlet on it, its not dual purpose. If its got a 14-50 on it then its spose to have 6 cable, would be legal to adapt to a welder recept.
As for being thrifty,, each app would ideally have its own outlet, I really don't care to play musical outlets. In my own case have 5 basic units with 6-50 on them, 2 on 10/30, 2 on 10/50 and one wired 6-50.
I understand free wire, short runs, some future proofing but I aint above utilizing economical as long as its adequate.
I been at this a long time. I done overkill, done future ****, cant remember the last time it worked out or was needed. The fear is wayyyyy greater than the reality.
I have spent 20 times the cost and effort I ever saved and never did it save the day. While its great to have 3/4 pipe etc I painted trucks from 100 ft of 3/8 hose just as well.

 

[sberry]

I said to my electrician the plan to use for the outlet, and the 8/3 was is conclusion.

I mostly will never need a 50A receptacle (since any welder I'm looking at are 30A anyway, a stove is 40A and a car charger is 40A.)

I need to pull ~80ft of wire to get to the front of the garage (pannel is in the middle of the back wall) if ever a full 50A is needed I'll put it on the back wall.

I still have a pull string in my attic always ready to use and all my wall finishes can be unscrew and remove to access the wall, ceiling.

You need a 50A recept, not really a 50 circuit. But a 50 may different for a welder than an oven or a charger. Again, most of the minimums are for single circuit in pipe. A buzzer allows near 80 ft of 12 on 50. There is substantial performance drop. Once 10 is used its not an issue, big difference between 12 & 10, not much between 10 & 8.
I have an electrician bud has 10 cable on his for 30+ years, burns a rod once in a while. When the machine is off its irrelevent. Doesnt know what wire is connected to it. Guy welds 15 minutes a year. I have him a dozen 1/8 6011 a couple years ago, got some left.

 

[justinthurn]

Please use 6/3 wire for your welding outlet and make it a 50 amp receptacle. If you or the next homeowner have an RV, you will be thanking me later. Running 6/2 does not work with rv's.

 

[sberry]

This guy needs a 12/2 or better for this machine. This is exaxtly the point. Not every circuit which is intended to run a modern welder needs a wire for someone in the distant future that "may" want an RV,, and he may not want to park what could be hundreds of dollars of copper "just in theoretical " case for someone he hasnt met yet and may not care either.

 

[sberry]

I been at this a long time and cant remember exactly how many welders and small garages I have hooked up. I have never had anyone come back and ask to have the welder outlet rewired for a motorhome,, not once. It would be different if it happened occasionally but not a single time in 40 years, never had one ask for a bigger welder or call to thank me for giving them more than they needed. I can say it again, never.
Never had one call to say the 1/2 air pipe we put in their 2 car or small pole barn needed to be changed out cause they decided to put in a truck tire service center in.
Never regretted using a 1/2 conduit to a light because I needed to run service to a e300a tig there. Only upgrages I ever add were to changed plans, new design, never wished I had 2 or 3 extra pipes everywhere just in case.
I have done a lot of stuff never utilized, put in inch where 1/2 would have been more practical, easier, cheaper and may have even worked better.