Thread: Three phase welder running of single phase

I don't think id be going any more than 200A on a single phase . After that you really need 3 phase. And if your welding plate above 6mm then you should be using plenty of grunt with no compromises especially in the industry welding all day

The arithmetic is quite simple. Assume a secondary voltage of 45 volts (probably whats available on less efficient machines). Open circuit maybe 70 volts. Gives a ratio of 45:230 ~5. 200 amps secondary roughly requires 40 amps out of a 1 phase outlet mmmm..... Calc is a bit simplistic but you get the idea. The Welders out there will have a better feel for secondary volts whilst welding. My own experience on jobs where there was inadequate power supply was to use the wee Caddy or a motor gen set.