Hey guys I've been working on retrofitting a 1993 Cincinnati Lancer 3 Axis Mill using LinuxCNC and a Mesa 5i25/7i77 combo. I've managed to get all three axes working but I'm having issues with the servo spindle.

The Spindle unit is a A06B-6059-H226 #H607

I've managed to get it to turn by setting the machine ready and CW signals low, but at 0V on the drive voltage pin (DA2) I get around 20 RPM and at +10V I get about 40. Even in low gear this should not be the case.

I'm very new to rebuilding CNC controllers so spare my lack of detail. I'm able to answer any questions if you have them.. Any help would be much appreciated!!