> Three-phase power for the RP06es helps.

Contrary to popular belief, the RP06 does NOT require three-phase power.
DEC supplied the US model wired for three-phase, but that can be changed.
The logic power supply is wired from one phase to neutral (nominally
120V), and the drive motor is wired between two phases (nominally 208V).
However, the drive is is a Memorex 677 which is rated by the manufacturer
for operation on 240V with no changes.

So if you don't have three-phase, you can wire it for 240V split-phase
with neutral (four wires including ground).  A typical residence in the
US does not have such a receptacle, though it's not hard to install one.

Alternatively, you could use a 240V:120V step-down transformer in front
of the logic supply.  Then you could run the RP06 on a 240V circuit with
no neutral.  Residences usually have such receptacles for electric
ovens, ranges, and clothes dryers.