I bought it knowing that it did not work. Some of the basic problems that I've discovered are as follows:
In 240v mode the arc welder seems to work fine however neither tig or plasma has any open circuit voltage.
When switching to plasma mode the relays appear good and I can hear and see them click. The digital current meter shows amperage range of 50 and dials down while adjusting the current knob however there is no open circuit voltage at the weld terminals.
When I switch to tig mode a hear a relay on the lower board click on at the same time the digital current meter shows up to 200 amps which I'm able to dial up or down with the current control knob. There is no HF buzzing between the points gap as it should.
When I had the lower power board out I noticed that of the 6 large black capacitors (in the pic) the 2 caps closets to where the DC power leaves the lower board to the upper board I only read apprx 285 uF all the caps are labeled as being 470 Uf caps. 4 of them read within 5% of their rating but the 2 seems out of spec. Do these 2 caps hint towards where the trouble might lie? btw the power leaving this bank of caps on it's way to the other board is only apprx 16 volts.. (((EDIT: 16 volts leakage from the positive to grounding frame))) I'm actually getting apprx 330v DC across the pos+neg leads leaving the capacitor bank towards the upper board.
Lastly for now I had the welder plugged in on my desk top in 120v mode and let it run for a while with the cover off while probing around with a digital infrared thermometer. Everything seems to fall within 70 to 90 degrees, however on the upper board I noticed at the 4 white ceramic 5w 47ohm resistors the temps reached about 160 degrees on one side and 140ish degrees on the other side. They have slight brownish discoloration as though suffering high temps. Is this a problem that they get this warm while just idling (not striking an arc or welding) These resistors are highlighted in blue squares in the attached pics..
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