[OTG-ZR2]

I want to make a 230v extension chord for my welder that runs off my dryer circuit. My welder draws 25A @ 230v at full load, max duty cycle 30%. I don't plan on welding anything on that high of setting, maybe 50% load.

I have a 50 ft 12/3 chord and a dryer plug.

Will this work?

[Soundy]

Chart here: Extension cord - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Extension_cord#Restrictions)

12/3 should be fine for 50', although I wouldn't go any further than that.

[RouRK]

its not smart, the welder draws more at full power then the wire is rated for.

im sure you'll be fine. its intermittent and you'll keep it on a lower setting then full load.

[pochacco_WL]

12/3 is not going to work, you'll just burn the wires cause it not rated for that kind of amperage. you must you 10/3 to make it work safely.

[GLOW]

i believe table 2 in the canadian electrical code shows for copper that #12 is rated up to 20 amps and #10 is rated up to 30 amps.

i think think you'd need #10 as pocha stated to be safe.