I just bought a Miller Thunderbolt Xl 225 AC/150DC welder and I'm a total newbie. I just registered on the forum tonight so I could ask these questions. I did some stick welding when I was a kid, but it's been about 20 years or so. Hopefully it's just like riding a bike. Well I'm planning to run a 50 amp circuit for the welder and my welding will have to be done outdoors, on the side of the house opposite our electric panel. That means I'll need about 75 feet of extension cord, or so, to get me comfortably outside. I looked into buying some #6-2 Romex that I could use to make an extension cord, and it'll cost just about 130 dollars or so for the length I need. I'm not too happy about using the Romex for an extension cord because it's so stiff and not really the stuff to use for an extension cord. It's really meant for permanent wiring. With the welder's 20% duty cycle, can I use a thinner gage wire than #6? Would a 75 foot long generator cable with 10 gage conductors and rated for 30 amps be adequate? Is there anything else anyone would recommend for an extension cord of this length? Thank you very much for any help you can provide.
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Thread: Help with welder extension cord?
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05-04-2007, 08:26 PM #1
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Help with welder extension cord?
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05-04-2007, 08:54 PM #2
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I have a 50' extension cord that I use on my MM251 its #10-2 and it works great. its some of that black "colored" (stranded wire) outdoor wire off a roll that you can get at home depot .and I put a male plug on one end and a female plug on the other, its flexible. and I can role it up like a big extension cord and store it. so I believe that you could get some of that # 8-2 wire at home depot . put some ends on it and use that
maybe some of the other guys would have a better solution than what I am saying. I'm not a electrician
also welcome to the forum , their are some great guys here
log in often , learn, and have fun
Welcome
.............
Richard
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05-04-2007, 10:38 PM #3
I have the same welder. I think you'll be happy with it. As far as your question on wire capacities is concerned, you're pushing 10ga pretty hard at 50 amps and you'll get more than 2% voltage drop over your 75 ft distance. 8ga would be better and the voltage drop would be right at 2%. (assuming 220-240 supply voltage)
I'd be a little concerned drawing a continuous 50 amps through permanent 10ga circuit wiring, but the welder isn't going to draw 50 amps unless it's cranked up to it's maximum amperage. The duty cycle will limit how long you can do that before the welder shuts down to cool off. Besides that, an extension cord is out in the open air and much less likely to overheat than Romex cable buttoned up inside a wall.
Bottom line: Use the 10ga wire and enjoy your new welder.
BTW, I bought a 50' 10ga heavy duty extension cord from Home Depot and replaced the plug and receptacle ends with NEMA 6-50 devices to match up to the welder and the shop outlet. Works fine.Tom Veatch
Wichita, KS
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05-05-2007, 08:10 AM #4
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I had to build an ext cord for a Lincoln 225 stick welder (50a) coming out of my dad's workshop so we could work in the driveway (also had to re-configure the panel but thats another story). I used 6-3 (stovewire), installed a plug on one end and receptacle on the other, it's about 16ft long. Trust me-this stuff is tough to work with. I've had to "train" the wire so I can roll it up but now that its done I don't think twice about it. Works good, probably cost about $40 total but I had to have it, the wire has a thick black insulated skin on it and I also put some electrical tape on the ends for a little added protection. Works great, handles the load fine-no problems. This will last me forever. Good luck!!
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05-05-2007, 11:21 AM #5
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#10 is very practical and common for this application. No way is it possible for this machine to overheat that wire. Do not use Romex as an extension cord, however. And since you won't use Romex, you'll need a 10-3 SJOOW service cord, also easily available at Home Depot and the like. Cords count the ground wire, Romex does not. (A 10-3 cord = 10-2 Romex for wires inside). Extension cords must be stranded wire. #10 Romex is not.
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05-05-2007, 05:59 PM #6
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I have the same machine and have been using number 10 wire and have never had a problem and I push my machine to the limit and again have never had a problem.
Wheelchair
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05-05-2007, 08:27 PM #7
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Extension cord
tube guy,
I bought one of these in 25' length for my 5 HP table saw and my Hobart 187. They have 25' and 50' lenghts listed.
http://search-desc.ebay.com/8-3-mig-...tensionQ20cord
Have a great weekend, Jerel
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05-06-2007, 06:23 AM #8
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05-06-2007, 07:53 AM #9
what wire
I have a 50' extension cord that we made with 10-3 and don't seem to have a problem with voltage drop or over heating of the wire. Dave
If necessity is the Mother of Invention, I must be the Father of Desperation!
John Blewett III 10-22-73 to 8-16-07
Another racing great gone but not to be forgotten.http://video.google.com/videoplay?do...modified&hl=en
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05-06-2007, 12:17 PM #10
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. Well I'm planning to run a 50 amp circuit for the welder and my welding will have to be done outdoors, on the side of the house opposite our electric panel. That means I'll need about 75 feet of extension cord, or so, to get me comfortably outside. I looked into buying some #6-2 Romex that I could use to make an extension cord, and it'll cost just about 130 dollars or so for the length I need. I'm not too happy about using the Romex for an extension cord because it's so stiff and not really the stuff to use for an extension cord. It's really meant for permanent wiring. With the welder's 20% duty cycle, can I use a thinner gage wire than #6? Would a 75 foot long generator cable with 10 gage conductors and rated for 30 amps be adequate? Is there anything else anyone would recommend for an extension cord of this length? Thank you very much for any help you can provide.
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