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I am new to the forum. This Econo Tig was used to join sheet metal and relatively thin flanges to tubing.
Today the machine only works at a low amperage appropriate to 24 to 26 gauge steel. Previously, pushing down the pedal was accompanied by a louder hum but no longer is true even when when both potentiometers are turned to maximum position.
There is no apparent burning marks on the circuit board. The potentiometers seem to work ok, the pedal pot maxes out at 1 k ohms because of the resistors between the Wiper and the legs. The Shunts were checked they are not open circuits. When welding there is 324 V to 343 V (some jumping around independent of Pedal position).
I noticed that there are board repairing shops but I need a diagnostic procedure to determine if in fact the is damaged.
Interestingly enough there follows a link to crgmark's thread that describes the opposite problem i.e.. the unit runs at maximum amperage continuously.
http://www.millerwelds.com/resources...587#post332587
Raymond
Today the machine only works at a low amperage appropriate to 24 to 26 gauge steel. Previously, pushing down the pedal was accompanied by a louder hum but no longer is true even when when both potentiometers are turned to maximum position.
There is no apparent burning marks on the circuit board. The potentiometers seem to work ok, the pedal pot maxes out at 1 k ohms because of the resistors between the Wiper and the legs. The Shunts were checked they are not open circuits. When welding there is 324 V to 343 V (some jumping around independent of Pedal position).
I noticed that there are board repairing shops but I need a diagnostic procedure to determine if in fact the is damaged.
Interestingly enough there follows a link to crgmark's thread that describes the opposite problem i.e.. the unit runs at maximum amperage continuously.
http://www.millerwelds.com/resources...587#post332587
Raymond
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