NO..there is NO ground used on 220V  Single phase home lines in N.A.....they use 2 hots ( usually a black and white/red of at least 12-14 guage for 30amps 10-8gauge for 40amps)  each Hot then shares a "COMMON" usually green. I have plenty of experience using dryer and stove plugs spliced to run 30 amp and 40 amp breakers. I ran 4x S9's off each 30amp breaker at times running up 24 S9's for 180 amps off of 6x 30 amp breakers on a 200amp. panel. Splicing the open wire end of 4 C-19 plugs to open wire of a Stove/dryer plug can be tricky if trying to fit all lines into a large marrette. I use large marrettes but also make damn sure all wires are well adjoined and soldered and then wrapped in tin foil BEFORE inserting into a marrette then shrink wrap, very very well reinforced so the splice can't be accidentally pulled apart and of course then well insulated with electric tape. In 3+ years I have never had a short or break or a connection even get hot. I still use this set up to run S9's as space heaters and for testing new gear at home before sending off to the Host.



Note that with most heavy gage wire the ground is NOT counted as a Conducting wire...In my case the dryer plug has green for ground (not used) and red and black for hot ...White for common/return. So I had to be sure the match the C19's correctly. On my PSU C-19 plugs the GREEN is common/return.