Im in the process of hardwiring my AD741 (it was previously wired to a plug) and im not sure which wire is which? I know the yellow/green is ground, and from my understanding, in 220, the other two are both hot. My unit has the power drive and I dont want to mix the wires up and somehow damage the circuit. The wires coming in are black and white, so I just need to know which to connect to which.