Lanse, sorry Im late, but heres my thoughts:
Every single phase straight 240 (NO 120) volt welder Ive encountered just use 3 wires, 2 hots (red n black) and a Ground (green/bare) soooooooooooooooooooooooooo
If the welder came with that cord and all 4 wires are used?????? my best educated "guess" is its EITHER:
A) A THREE PHASE WELDER (240 or 480 VAC) in
which case: (Of course, it requitres 3 phase)
Red, Black, White are all hots
Green is safety case equipment ground B) Its a SINGLE PHASE 120/240 WELDER that
uses some 120 volts for controls etc but
240 volts single phase for welding If it uses all 4 wires and is a 120/240 volt single phase welder, the plug and matching receptacle need to be a 3 pole 4 wire grounding type (4 pins) of the appropriate amperage rating........ WE CANT SAY SITTIN HERE BASED ON YOUR POST IF ITS 120/240 SINGLE PHASE ORRRRRRRRRR 240 OR 480 VAC THREE PHASE MY PURE GUESS WOULD BE ITS A THREE PHASE WELDER since most 240 welders are straight 240 and dont need or use any 120 (which is when and why a white Neutral is required) Once you determine the welders input requiremetns its easy to find the correct plug and receptacle well duhhhhhhhhhhhhhh John T
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