03-03-07: Angus80808Do not think of it as 2x 120V. It is single phase 240V. And no you will not need the neutral conductor. Just the two hot 240V conductors and the equipment grounding conductor.
Yes, as you mentioned, I will connect to a 2 pole breaker (2x 120V). The wire is #10 awg and will use with a 20 amp circuit...(or maybe 30A??) This makes sense to me.
As for the wire size being #10 awg, because of the 20 amp receptacle you are using the branch circuit over current device, (the 2 pole breaker in this case), must be 20 amp. Not 15, not 30, it must be a 2 pole 20.....
And as Ngjockey said in his post have an electrician do the job. 240V will kill you just as dead as 120V
Jim