Charles, most don't actually use all three phase, just use two phases to
give 415v to reduce the current - this can easily be determined opening up
the back of the welder by seeing if it has a three bobbin or a one bobbin
transformer. If indeed it is one using two phases you will get away using a
suitably sized 240 to 415 transformer.
(pst - want to buy a big 240 to 415v transformer as I have one surplus<G>)
I've seen mention of using power-factor correction cap's to generate a "wild
leg" for welders - it was on one of the american metalworking sites, perhaps
Practical machinist? The real problem is likely to be getting 380 - 415
volts in though. I think a rotary convertor is going to need a *big* motor
though, if the welder's expecting to pull (e.g.) 5 KVA form 3-phase, the
motor will need to be 10HP or more to do the job, and will stiull need some
way of stepping up the voltage - most often this would be an old 240/415
Dave H. (the other one)
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