Basically is it possible. Have seen posts of guys in America doing it with a few capacitors on other machines. Would like to do it as the welder is on a purpose built rough terrain trolley. Any help would be great
Are you reffering to the "Haas Kamp" conversion ?
I think you will find the caps might go to the neutral, as our 240vac is in 2 phases,
might not work in your situation
The three coil bobbins on the main transformer core and the six diodes ( in the form of 3 dual-diode modules ) mean that this is definitely a 3-phase machine.
There is a circuit diagram of the Murex 235 on Page 15 here:
The secondary is configured in Star ( Wye or Y ), and I think the primary is too. Only the three phases are connected, neutral is not used.
The three primary windings have tappings to select input voltages of 380 ( Europe ) or 415 volts ( UK ). The Haas-Kamp method requires the three primary coils to be driven as three separate loads in parallel from the single-phase supply. The third coil start/end is reversed with respect to the first coil, and the second coil is connected via two motor-run capacitors of about 60uF. See:
However, with the UK single-phase supply of 230v, even if the primaries are set for 380v they will be under-driven, to only 60%. Instead of 20 to 30 volts, the open-circuit output voltage will be only 12 to 18 volts. Even when set to the maximum, the machine may only be able to weld at 30 Amps.