Huge diodes for a diy TIG welder project?

Aug 14, 2004 1 Replies

Today i recovered a couple of handfuls of huge anode stud mounting diodes from the old 3 phase UPS that would run the whole building during a power outage (until the diesel generator came on line). The complete machine, all



3 tonnes of it was off to the scrappy but i had time to save some bits, including a couple of massive 5kg alloy heatsinks.

The question is will any of this stuff be usable in a 'build a welder project' (?).



The diodes are 1.25" across the flats of the hex bolt and the thread is



0.75" diameter. Coded PRX 1210620200 there is no makers code or id but most other semiconductors (the clamp mounted SCRs) were from SEMIKRON so the diodes possibly are too.

I've searched with Google to find some specs but to no avail. Does anyone know if these monsters will fill the job?


They will be rated for 50Hz, if you are trying for an inverter style MIG, the diode's capacitance may work against you- they won't be fast switching. For a rectified DC welder though, they should be fine.

Steve

Join the Discussion

Have something to add? Share your thoughts — no account required.

Didn't find your answer?

Ask the community — no account required