Extension Cord for welder

[Sublifer]

I got an electrician at work to hook me up with his supplier. I'll let them figure it out. I gave them my specs and I will not go above 6 gauge but if they tell me 10 gauge is sufficient then I'll tell them I want 8 gauge. It'll be 8 or 6 and at a savings of $30-40 I may as well end up getting the 6.

 

[Dr Dave]

Have you priced a breaker, wire and outlet for your garage? This may be your best option. It is a pain to use wife's oven outlet, door cracked, dirt, noise and bugs get in Been there and done that! I've found it to be cheaper to do it right the first time.

 

[KWentling]

So here is what the NEC book said in 1995. "Each welder shall have an overcurrent protection (breaker) rated or set at not more than 200% of the rated primary current of the welder" For conductors: "Conductors that supply one or more welders shall be protected by an overcurrent device rated or set at not more than 200% of the conductor rating"

The way I read that is your cord would need to be able to carry 1/2 of the 50 amp breaker rating or 25 amps, which would allow you to use a 10 gauge cord.

Kim

 

[Sublifer]

Have you priced a breaker, wire and outlet for your garage? This may be your best option. It is a pain to use wife's oven outlet, door cracked, dirt, noise and bugs get in Been there and done that! I've found it to be cheaper to do it right the first time.

I've thought about it but don't plan on living in this house too much longer. My main breaker panel cannot support additional breakers. It has 6 double pole breakers. It is also on the opposite side of the house from the garage.

Yes, I'd rather do it right but I am not willing to sink $1000 into it and let it go to waste when I move in a year (I hope).

Kim: Both of those statements appear to be for the breaker and imply not to use bigger than a 100amp breaker in the case of a 50 amp rated load.

 

[PILOON]

My welder is rated at 230 amps and I use an extension made of #10 household heater wire. (red cable).
Face it, you probably won't use greater than 5/16 rods an generally only 1/8. and if you look at the current settings to use those rods and convert back to the amperage draw at 220volts you will find that #10 gauge covers your needs.

Now to err on the safe side I would ONLY use #10 as an extension and not permanently wired in the walls.
As in all cases be sure that the breaker is properly rated for the wire used as that is your protection.

With the setup described, a buddy once split his excavator bucket and repaired it using my rig. Probably welded for a solid hour non stop using 5/32 rod and the extension never even felt warm!

 

[PILOON]

Maybe best explained this way.
It is all in the watts drawn. Watts is voltage x amperage. A given rod uses X amps at the welder secondary and we know the amps range required for any given rod.
Most welders run in the 30/40 volts secondary X the current needed for a specific rod.
Convert that to watts and calculate what you need at 220 and you'll find that if you run 1/8 rods you can weld all day on a #10 extension. (well perhaps not 500 ft long due to voltage drop, but 20-30 ft should be no problem)
Just be sure that the proper rated fuse/breaker is used.
One downside might be that it be a bit more difficult to strike the ark at first if there is some voltage drop.
Shucks I have welded using 3/32 rod on a 24 volt 25 amp transformer. Tricky to do but the welds held.

 

[xtn]

Welders commonly used transformers. Their output rating is not the same as their draw. Find out the maximum current draw and size the dedicated branch circuit wiring and overcurrent protection accordingly.

 

[KennyG]

This is something that gets recycled here periodically, so I'll just weigh in with my own experience. I have a Lincoln 180 wire welder. I've run it hard enough from time to time that it has shut down from exceeding the duty cycle. I have it on a 30 amp circuit with #10 wiring and have never tripped a breaker. I made up a 50 foot extension cord with #10 motor wire I bought cheap off Ebay and added ends. When the welder shut down, I checked the cord and could not detect any increased temperature at all. It would have to be a pretty big welder before I would worry about using my #10 extension cord. The NEC wiring standards established for wire running in enclosed spaces with constant full load where the heat builds up.

 

[KWentling]

Kim: Both of those statements appear to be for the breaker and imply not to use bigger than a 100amp breaker in the case of a 50 amp rated load.

Thats right. But it says to not use a breaker rated at more than 200% of the conductors ampacity. If the ampacity of a 10 gauge wire is 30 amps, 200% of that is 60amps, so 10 gauge should be OK for the 50 amp breaker he has. Am I reading that wrong?

Kim

 

[Qapla]

All of this sounds interesting and, at times, confusing. I still don't see the point of extending the welder power cords and having to lug a welder in and out of the garage when you can extend the welding cables much easier and leave the welder where it sits - unless you are using a wire welder.