Hi Tom, I can run my Z Axis servo motor with no problems (while in the open loop mode) by issuing a move command. When I close the loop and enable the drive the Z Axis runs away and will hit the limit. Is it possible that the encoder (glass scale) is reading backwards? If so go can I correct that? Should reverse the servo power and tach wires or can I reverse the A & B channels of the encoder in Kanalog? Or can it be as simple as reversing the Dac output wires for that drive on Kanalog? All scales, drives, & motors are wired the same. X & Y Axis work fine. Thanks Steve