Thermal Arc Welder 150 GTSW went ''pop''

Question

I was welding some mild steel when my tig welder went pop. Blew the breaker and a puff of smoke. I opened it and found a few resisters had blown. I replaced the Mosfets, Diodes, Resistors and powered it up again. Unfortunately went pop again but different things blew. Does anybody have any suggestions where I can get a schematic or where I should look for the problem? Thanksjim