Short circuiting arc control station for multiple operator welding system

Claim 1

A welding system for providing welding current to both gas-metal arc spray transfer stations and short-circuiting arc stations from a single source of supply, comprising: a common power source providing direct current power at a substantially constant potential, said potential being selected to accommodate the requirements of spray transfer welding but being unsuitable for short-circuiting arc welding; a first operator station including a spray transfer welding gun and wire feeder means for supplying welding wire thereto; first cable means connecting said spray transfer welding gun directly to said common power source to provide direct current power for spray transfer welding; a second operator station including a short-circuiting welding gun and wire feeder means for supply welding wire thereto; a short circuit arc control unit at said second operator station for selectively reducing the direct current potential of said common power source for said second operator station said arc control unit comprising an input and an output, a first resistor grid comprising a plurality of parallel-connected resistors connected in series between said input and output, a second resistor grid comprising a plurality of resistors, switch means in series with each resistor of said second resistor grid and selectively operable to connect selected resistors of said second resistor grid in parallel with said first resistor grid, and reactive means connected in series with said first resistor grid between said input and said output; whereby voltage disturbances from one of said operator stations are effectively isolated from the other of said operator stations; and second cable means connecting said arc control unit in series between said commmon power source and said short-circuiting welding gun, said first and second operator stations being connected in parallel with each other across said common power source.