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I am getting ready to purchase a welder, and I have decided to go with a 220 volt unit from Lincoln, Miller, or Hobart. My question is about the house wiring. Is a 40 amp two pole breaker with 8 gauge solid core wire sufficient? I am looking at a welder in the "180" ballpark and the wire run is very short (four feet) from the service box to the outlet location in my garage. Thanks!
Temvette72
P.S. I will also someday like to run a compressor from the same outlet. (not at the same time as the welder).
As long as you are not welding for extended periods everything should be fine. By extended I mean several hours without many breaks (but who welds without short breaks on their Vette?)
I'm not sure how much current the welder will draw, but I don't think that it should be too close to the 40A rating of the breaker. If it does happen to be a serious draw, then at least the wire size is sufficient to withstand it.
Also, if you do need to add a larger size breaker later, you should also up the wire size to 6
because a size 8 copper wire in cable sheath is rated at 40 amps for type TW and UF.
The compressor should also be fine on the same circuit if not using at same time.
It's always better to slightly oversize wire than the breaker....we don't want you to burn down your garage!
It depends on the input requirements of the welder, but with only four feet from the box it sounds like it would be easy to upgrade the breaker and the wiring if necessary.
Thanks for the reply, guys. I already bought the wire and the breaker before I asked the question (sounds familiar, doesn't it!). Home Depot has the 8-3 wire in stock, and six gauge was special order. I went with the stuff they had in stock, but now I think I might go with a 60 amp breaker and 6 gauge just to be sure. I can return the 40 amp breaker and the wire was only 10 bucks. Does it matter if I use stranded wire or is solid wire the way to go? Thanks again.
I'm riunning a Miller 250 on a 50 amp breaker and a 50' extension cord. Works just fine. I think the extension cord is 10/4 and is the real flexible stuff. I used a 4x4 metal box on the female end, and made a jumper so I can run my 110 volt plasma cutter off the same cord.
I would suggest building an extension cord- someday you'll want to have the welder more than 4' from the wall.
I ran 240 volts to my barn last summer and I had to calculate the voltage drop because it was a long run. I still have the spreadsheet calculator I made for deciding what wire I needed. I just put in your 4 ft. run and your 8 guage wire is plenty for a 60 amp 240 volt circuit.
I would strongly suggest that the compressor doesn;t go on the same cicuit as the welder. Sure you won't run them at the same time now (or on purpose), but in the future you may want to. For the amount of work it will take to do 2 circuits at once, you'll be happy.
For Mig welding it takes about 18-20 Amps to strike the arc and thereafter less amps. Of course it depends on the voltage setting on the welder. The higher the setting, the higher the current draw.
For stick welding it takes about 30 amps to strike the arc and thereafter less.
Ever thought of getting an electrician to hook this up for you?
If you don't size the wire correctly you risk the chance of having a
fire. If this happens to create a fire you may risk losing your garage,
your cars, your house (if attached to the garage) or even put you and
or your family's life at stake if you install it incorrectly.
I see were you are coming from as a DIY guy myself but, there are some things
better left to a professional.
Ever thought of getting an electrician to hook this up for you?
If you don't size the wire correctly you risk the chance of having a
fire. If this happens to create a fire you may risk losing your garage,
your cars, your house (if attached to the garage) or even put you and
or your family's life at stake if you install it incorrectly.
I see were you are coming from as a DIY guy myself but, there are some things
better left to a professional.
sorry just my two cents.
Riggs.
Point well-taken. I am pulling the wire and letting "my cousin Vinnie" the electrician make the connections. I wanted to have all the materials in hand before I bugged him.
Temvet72,
I also forgot to tell you that there is a spec tag on the welder that will give
you the (FLA) full load amps and max fuse/breaker size. This is what you should
size your circuit buy.
Your circuit size on the spec welder tag will be some where between 40 to
50 amps this will require a number 8 gauge wire. I have found that the cord
that comes on the welder will general be number 10 gauge cord, which will
be fine being factory installed, They size it smaller because it is considered a
momentary load but may get warm to the touch when used for an
extended period of time.
Temvet72,
I also forgot to tell you that there is a spec tag on the welder that will give
you the (FLA) full load amps and max fuse/breaker size. This is what you should
size your circuit buy.
Your circuit size on the spec welder tag will be some where between 40 to
50 amps this will require a number 8 gauge wire. I have found that the cord
that comes on the welder will general be number 10 gauge cord, which will
be fine being factory installed, They size it smaller because it is considered a
momentary load but may get warm to the touch when used for an
extended period of time.
Hope this helps,
Riggs.
All the input is most definitely appreciated! I have the 8 gauge pulled and a 40 amp breaker ready to install at a future date. As a side note, I am waiting a few pay periods now to get that welder....I just brought my other fiberglass toy (boat) in for it's annual service. Now I'm $500 light! OUCH.....Temvette72