If the rig is like the one I have, the 120 volt duplex has one receptacle running off each winding (tab is broken on the line side terminals) and the neutrals are common...just like an Edison 3 wire. (There is 240 across the line side prongs of the receptacle). I have used it with two 120 v male plugs on short cords spliced in a weatheproof junction box to a single 4 conductor cord (line, line, neutral, equip grnd) running to a twistlock. Sounds like your situation. Would I do it for someone else?? NO WAY!
