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Fadal X axis only works in "rev" direction (DC)


Oct 15, 2014
Olive Branch, MS
1992 FADAL 4020
Glentek DC AMPS and Motors (GM4050)
Axis cards are all -6A

I recently rebuilt all DC servo motors and replaced all resolvers.
After rebuilding the motors everything worked great.
I did notice some noise coming from X axis motor and determined it was tach brushes because I replaced the tach brushes on the Y motor and is silent when running but I did not replace tach brushes on X motor and it was noisy after rebuild.
I recently pulled the X motor back off to replace tach brushes.
After replacing the tach brushes on X motor I can not for the life of me get it to work in the "forward" direction no matter all possible combinations of tach and motor leads.
If I jumper "rev direction" on X axis control card card the axis works great but obviously directions are reversed. This tells me everything is working great the tach, motor, and resolver. I can not for the life of me figure out why it will not work in normal "forward" direction.

Maybe just maybe the tach is 180deg out of phase? Is that even possible?