Hi Bruce and
to the forum.
Unfortunately, there is unlikely to be any documentation for the actual motor, and I'm not sure which controller the MX50A-3.0 is that you are referring to.
Hopefully, it's the BAC-0501:
The motor should have three thick phase wires
(Yellow, Blue and Green) which connect to the corresponding coloured screw terminals
(along with the Red and Black battery cables) and five thin Hall sensor wires
(Black, Red, Yellow, Blue and Green) and these should be connected as shown in the above diagram and the
Connection guide.
Programming this controller requires the PI-200E USB lead:
This lead should allow you to set the various controller parameters using the
PD-282 programming software.
Alan