Originally Posted by roverjohn
All welders use some sort of power cord, extension or not. If the cord is sized properly and terminated correctly there is no difference between an extension cord and hard wiring. You have no idea, based on the info provided by the original poster, that the cord is masking or confusing anything. The cord appears to be helping but you choose to ignore that. I took the time to go look at the Panasonic machine the guy has and it appears to be inverter based but I could be wrong because they never call it that. The guy could test his current wiring by simply borrowing another welder and seeing how his circuit handles it. If it's fine with another welder then there is likely an intermittant fault within his machine.
You have enthusiasum. Here is some background for you so you don't think I'm talking out of my backside...
I work for The Lincoln Electric Company, we are the worlds largest manufacturer of arc welding equipment and electrode. I have a Bachelors Degree in Welding Engineering form the Ohio State University. I can tell you with 100% certainty that using an extension cord on any manufacturers welder is foolishness. You are not helping the machine or your circuit breaker by adding more resistance to your circuit(in the form of an extension cord). Electricity is not plumbing.
As far as advice for the Airstream trailer. The frame is mild steel. Airstream is located in Jackson Center Ohio near where I used to live, and it is fine to weld there frame. You are confusing a semi-truck frame (which is not to be welded due to heat treat issues), and a camper frame.
I don't mean to be a jerk but we don't want to misinform anyone. Welding is a very important process that needs to be carefully applied because many times your safety is riding on proper welds.
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