Home electrical help (welder)

[01somta]

Calling all electricans, EE, people with 220 welders, or whoever wants to give their input. I just bought a lincoln 175 welder, It runs off of 220. Well here is my question the plug in the garage is 220/30amp, but the lincoln recommends that I have 40amp breaker. Is this just a "recommendation" from lincoln or is it manditory that I have a 40amp?

[Paul_J]

I swapped my 30 amp breaker for a 50. I use a Miller 175 similar to your Lincoln. I would be more concerned about the wire size from the breaker to your outlet. How far is the outlet from the breaker?

Here's a website where you can calculate wire size. http://www.elec-toolbox.com/calculators/voltdrop.htm

[69Bbird]

A 30amp circut should have 10gauge wire and a 40amp should have 8gauge. I'd run it on the 30 the worst thing that will happen is the breaker will trip.

[01somta]

I swapped my 30 amp breaker for a 50. I use a Miller 175 similar to your Lincoln. I would be more concerned about the wire size from the breaker to your outlet. How far is the outlet from the breaker?

Here's a website where you can calculate wire size. http://www.elec-toolbox.com/calculators/voltdrop.htm

The plug was just put in right under the breaker box, it is a 10ga and only about 2.5ft. at the most.

[parsonsj]

If you can upgrade the wire, do it and go to the bigger breaker.

jp

[Paul_J]

At that short a distance and using the Max amperage of your breaker (40A) to calculate wire size, the #10 is fine. If you plan on using your machine in the upper range I'd swap the breaker. If not, just use it and see if you trip the breaker. My Machine rarely sees the upper end of it's range. I'm about 10' from my panel and I use a #10 wire.

[72nova]

I agree with John, use the 30 amp and see what it does. If it it trips then switch it to a 40 amp breaker. If you do switch it use #8 wire, this is code.