Welder hookup

[mendozer]

So someone on here brought this up a few years ago but I wanted to learn why the answer is what it is.

I have a Lincon PowerMIG 210. It's a dual purpose welder. The power input specs in the manual state that the max input draw is 27 amps. So it says to use a 40 amp breaker (makes sense with the 27 amp load) with 12 AWG. What? In what world does 12 gauge support that? My brain can't comprehend how that's approriate, and not using 8 AWG. does it have to do with how the welder somehow regulates the voltage or inverts something? Or is it saying that 27 is the absolute max, and 12 AWG is pushing the limit for that.

To play it safe, I was going to just use 10/3 instead of 12/3 romex, for piece of mind.

 

[Norcal]

So someone on here brought this up a few years ago but I wanted to learn why the answer is what it is.

I have a Lincon PowerMIG 210. It's a dual purpose welder. The power input specs in the manual state that the max input draw is 27 amps. So it says to use a 40 amp breaker (makes sense with the 27 amp load) with 12 AWG. What? In what world does 12 gauge support that? My brain can't comprehend how that's approriate, and not using 8 AWG. does it have to do with how the welder somehow regulates the voltage or inverts something? Or is it saying that 27 is the absolute max, and 12 AWG is pushing the limit for that.

To play it safe, I was going to just use 10/3 instead of 12/3 romex, for piece of mind.

Welders have different rules, based on the duty cycle of the machine, and why use 3 conductor, 240V loads do not require neutrals, and tapping off the circuit for a 15A 120V receptacle is not kosher.

 

[matt_i]

in basic physics, the welder itself goes into thermal overload before the feeder wire does.

And then the welder has to stop and cool off assuming you used it long enough to drive it to that point. But the incoming feed cools off faster than the welder.

Repeat ad infinitum. Not the same for motor or resistive loads where the current draw can be hours/days/weeks/years of constant current flow and so the feeder has to be sized appropriately for the heat of conduction.

 

[Bretny]

You really need to take into account the wire length too.

 

[sberry]

Yes, length for voltage drop ,,, slightly different than thermal. I am a fan of 10 wire for a couple reasons. It will support a larger welder and breaker to 50 for those. The minimum wire of 12 is for single circuit in pipe, cable needs a size larger and the 10 fits the terminals on the device so much better and more secure. The 40 listing for this machine is when used with the minimum wire size, it comes 50 plug, its legal on a 50 circuit.

 

[mike93lx]

So someone on here brought this up a few years ago but I wanted to learn why the answer is what it is.

I have a Lincon PowerMIG 210. It's a dual purpose welder. The power input specs in the manual state that the max input draw is 27 amps. So it says to use a 40 amp breaker (makes sense with the 27 amp load) with 12 AWG. What? In what world does 12 gauge support that? My brain can't comprehend how that's approriate, and not using 8 AWG. does it have to do with how the welder somehow regulates the voltage or inverts something? Or is it saying that 27 is the absolute max, and 12 AWG is pushing the limit for that.

To play it safe, I was going to just use 10/3 instead of 12/3 romex, for piece of mind.

Nevermind

 

[sberry]

He was curious, its a legit question. Not saying must or have to.

 

[JeepJohn62]

With respect to other posters,
Why mess around with this small wire?

I would use a 50A breaker with #6 wire rated for the breaker. You can run almost any welder from that plug. You're done and safe.

The typical welder plug will mate with this and all is happy.

John

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[sberry]

We are not saying you cant do that but that you don't have to , its not required and most of the time doesn't help. Its worth exploring this to get some understanding as to how it works. Not much learning if we simply repeat the first thing we ever heard about it.

 

[matt_i]

It makes sense to "conventional size" if the circuit could be used for multiple purposes, sort of like "I want a 240vac outlet in my shop" then it might be wise to prepare for all potential uses.

Otherwise the smaller wire is of course more economical but would be dedicated to that welding machine or smaller amp devices.

 

[sberry]

The only machines that call for 6 cable that come factory 50 end are 250 class migs. Pretty much everything else runs from 10 and new ones allow for 12 cable, 14 in pipe. Got to reduce the breaker to 30 for these light circuits. No one thinks the 14 is a great idea and the outlet termination is not rated/listed for it.

 

[TRWham]

Apparently, when NFPA publishes wire ampacities in 310 they are infallible, but elsewhere in the very same book they are idiots for allowing very specific, logical and limited deviations to those numbers.

 

[Bretny]

With respect to other posters,
Why mess around with this small wire?

I would use a 50A breaker with #6 wire rated for the breaker. You can run almost any welder from that plug. You're done and safe.

The typical welder plug will mate with this and all is happy.

John

Sent from my SM-A102U using The Garage Journal mobile app

This is what I would do also. I think I have like 2ga wire for my 50a welding circuit, I had the wire.
My plasma is 240v 20a and I now use other things off that circuit.

 

[mendozer]

Ooh lots of feedback, nice. Yes I know I CAN make it to allow for future uses, but this plus will be just for the welder. I'm wiring everything new so I have the luxury of making a welder-only plug.
So if 40% duty for example, is that saying it's only going to draw that ratio of the total amps which is why 12 gauge is acceptable?

 

[mendozer]

I'm also installing it right below my panel on the wall so I can easily upgrade wiring later if it needs to happen. But I didn't know about the 3 conductor wire thing you mentioned. I figured it needed all four, but I guess that's for 120v on the same circuit. So even my dust collector circuit doesn't need 3 conductor

 

[Bert_]

Ooh lots of feedback, nice. Yes I know I CAN make it to allow for future uses, but this plus will be just for the welder. I'm wiring everything new so I have the luxury of making a welder-only plug.
So if 40% duty for example, is that saying it's only going to draw that ratio of the total amps which is why 12 gauge is acceptable?

Yes. The welder can draw 27 amps. But it will only pull 27 amps at maximum output, which is only 40% duty cycle. So it will pull 27 amps for 4 minutes, the welder and the wire will be able to cool down for the other 6 minutes.

 

[mendozer]

Thanks to everyone for explaining the different aspects of that, the draw, wire cooling(didn't even factor that in my thought), and the wiring options

 

[wyliesdiesels]

https://www.ecmweb.com/national-electrical-code/qa/article/20889547/code-qa

 

[sberry]

Nothing else I am aware of comes with 6-50. A welder circuit really isn't for other equipment, other stuff on it would be subject to a rather narrow set of conditions, a comp 3 hp may,,, and it would use a wire in the same range with minor exception. Other stuff that comes with plug uses a different recept.

 

[mendozer]

Nothing else I am aware of comes with 6-50. A welder circuit really isn't for other equipment, other stuff on it would be subject to a rather narrow set of conditions, a comp 3 hp may,,, and it would use a wire in the same range with minor exception. Other stuff that comes with plug uses a different recept.

Yes it's dedicated. Sorry I meant the dust collector was also on 240 not the same one. I have scrap 12/2 laying around so I'll just save money and use that

 

[Bretny]

I'm also installing it right below my panel on the wall so I can easily upgrade wiring later if it needs to happen. But I didn't know about the 3 conductor wire thing you mentioned. I figured it needed all four, but I guess that's for 120v on the same circuit. So even my dust collector circuit doesn't need 3 conductor

If your installing right below your panel what is it going to be 4ft of wire at the most? So less than $10 difference to use the correct wire for the circuit the first time.

 

[sberry]

Yes it's dedicated. Sorry I meant the dust collector was also on 240 not the same one. I have scrap 12/2 laying around so I'll just save money and use that

I believe it might be 12 in pipe, needs a 10 cable and it fits the terminals on the outlet so much better.

 

[u2slow]

If your installing right below your panel what is it going to be 4ft of wire at the most? So less than $10 difference to use the correct wire for the circuit the first time.

'Correct wire' is based on his actual welding machine.

I use 6-20R receptacles throughout my shop for 240V.... then I have a 10' home-made extension cord with 6-20p on one end, and 6-50R on the other end for the welder.

 

[Bert_]

If your installing right below your panel what is it going to be 4ft of wire at the most? So less than $10 difference to use the correct wire for the circuit the first time.

#12 or #10 or whatever the machine calls for is the correct wire.

 

[sberry]

It's also so short v drop isn't an issue.

 

[JeepJohn62]

Get one of these. You can run 6 welders at a time!

Sorry - couldn't resist.

Sent from my SM-A102U using The Garage Journal mobile app

 

[Bert_]

Get one of these. You can run 6 welders at a time!

Sorry - couldn't resist.

Sent from my SM-A102U using The Garage Journal mobile app

You find one for a 6-50, the plug most welders come with, and we can have a party.

 

[JeepJohn62]

You find one for a 6-50, the plug most welders come with, and we can have a party.

I'll bring the beer and a fire extinguisher! Count me in.

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[mendozer]

Ok I picked up 10/2 UF since they didn't have NM on a spool and I didn't want 20 ft. Damn that stuffs a PITA to strip the outer jacket. Got it all wired up. I had the 6-50 from my previous outlet box i used in the last house.

 

[Bert_]

Need to get a connector in the metal box with the welder receptacle. Otherwise looks good. Could be neater but not bad for DIY.

 

[mendozer]

Oh! Shoot I didn't notice. You meant the cable clamp. **** now I have to undo the receptacle. Ugh. Those screws were a PITA

 

[nadogail]

It was a revelation when I discovered the factory installed "pig tail" power cord on my Stickmate is made of 12 AWG cable.

I used 8 AWG THHN to a 50 Amp breaker in the main panel connecting it to a dedicated receptacle. If I am wrong, sue me.

 

[sberry]

The 8 will support any welder that comes with factory 50 end including heavy wire feeders. I forget what rated is on a 252 but its a lot at 60% and will hit 300 or so amps with a special set up. Using 035 solid C25 it will run from the 10 without a problem.
Millions of circuits for buzzers were installed 10 cable to 50 fuses. The wire coating is better today,,, also volts are 20 or more higher than they were when they designed the machine and wrote the code. This has made the wire more efficient.

 

[nsula_country]

Nothing else I am aware of comes with 6-50. A welder circuit really isn't for other equipment, other stuff on it would be subject to a rather narrow set of conditions, a comp 3 hp may,,, and it would use a wire in the same range with minor exception. Other stuff that comes with plug uses a different recept.

I acquired a 1950 DeWalt 3HP 14" RAS that had a 6-50 on the end of the cord. I have 3, 50A breakered, #6 wired receptacles at the shop. Can plug in the RAS, Welders, or RV into any of them...

CT

 

[Bert_]

I acquired a 1950 DeWalt 3HP 14" RAS that had a 6-50 on the end of the cord. I have 3, 50A breakered, #6 wired receptacles at the shop. Can plug in the RAS, Welders, or RV into any of them...

CT

An RV is not going to have a 6-50. The 3 hp saw would run on #12 thhn or #10 same as the welder. The saw should probably have supplemental protection since the 50 is to big a breaker for 3 hp.

 

[nsula_country]

An RV is not going to have a 6-50. The 3 hp saw would run on #12 thhn or #10 same as the welder. The saw should probably have supplemental protection since the 50 is to big a breaker for 3 hp.

I errored. RV is a 14-50. When I ran the Welding receptacles I pulled a neutral also (all #6). Welding/RV circuits have a 6-50 and a 14-50 next to each other. I have one under lean shed and one at end of shop opposite load center. Receptacle at load center is a 6-50 only.

#12 or #10 isn't going to power 2, 15kw roof top AC's on top of the rest of the load. Can be used as additional "guest" quarters.

Reason for the dual 6-50/14-50 was I thought about building a 9-10kw electric brewery. Could dual purpose the circuit. It required a neutral for controls and pumps. Ended up building out a gas system.

RAS has an Arrow-Hart manual motor starter with O/L.

Throwing poop in punch bowl, also have a 5HP B&D Industrial 16" RAS. 6-50 plug... Not HP rated for that... But it is a BEAST!

CT

 

[sberry]

I have the plug on my RAS too but it didnt come with it. I put a 2 pole breaker on it, got a cooler truck we did the same so we could plug it in to 50A