Chinese welder excess current

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While going through a bunch of old posts I ran into this thread, which I made a brief comment on.  http://weldingweb.com/vbb/showthread.php?t=18718An individual was having trouble with burn through even at extremely low amperage settings, and I recalled a similar problem that I had encountered.  The welder in question had a front panel nearly identical to the Longevity 200 amp AC/DC pulse unit with plasma that I have been using of late, and I noticed an issue that was very frustrating until I figured out what was going on.After doing some stick welding with the unit, I switched to GTAW mode, and no matter how low I dialed the current, I was having blow through problems on thin wall mild steel tubing.  What I discovered, is that the "Arc Force" knob affects the minimum current output in GTAW mode, but it does not show up on the LED display.  I guess my point is that if you have a similar machine that seems to be outputting significantly more current than you are requesting when in GTAW mode, turn the "Arc Force" knob to zero.As I did not have a clamp on amperage meter, I don't know exactly how big the effect of the "Arc Force" control is for low amperage GTAW, but I know it was definitely enough to make the weld puddle uncontrollable.