Thermal Arc 400GMS max output?

[welderdude]

Hi everyone,

I have a thermal arc 400gms that i scored off of ebay dirt cheap ($580). It can run off of single phase or 3 phase. Going by the label on the back, it shows 280 amps as the max on single phase, but I can set the amperage on the panel display all the way to 400 amps on single phase.

I'm wondering is it wont go past 280 amps even when its set higher, or if it will fry something internally. I'm not willing to test it out and see if it lets out the factory smoke.

Thanks!