I have limited knowledge of the component involved, is it possible everything is build in the big brown box on the pic?
The diode needs plenty cooling so that does note make sense..
Hi thanks for your attention there are no diodes visible, only this big "capacitor" box, but written on it "kontensator".
I tried few rods: 7016 special was good, 6011 on the limit, 6010 not possible, 7018 DC only, not good, and it felt just like AC transformer.
Maybe the capacitor is only to smooth the arc, but still I don´t understand the DC simple on the front panel.
I think you could find that DC means Duty Cycle 30% at 170 Amps and 40% at 1?0 amps.
The capacitor would I guess be on the input as a power factor correction to the input stage, we see these fitted to the old transformer type welders from time to time.
Thanks for open my eyes, I had my mind completely closed as those informations looks different to days machines.
Now is only to find good home for the thing