In this post we are going to see how to use an AC Servo motor as a spindle, using Mach4 and the C82 with ESS, for this case we will use a DYN4 servo driver and Mach4, ESS Plugin V 275

 Configure Servo Driver

  • Connect to the DYN4 Servo Driver using the CA-MTUSB-FR1 Tunning Cable.  
  • Set the number of pulses per revolution of the encoders, for this case we are going to use 500 pulses per revolution.
  • Keep in mind that you also must tune the driver with a load of your machine.


  • Configure/Plugins/ESSV275

In the ESS Plugin, set the Spindle Type to SS Motor for using a Step and Direction Spindle and set the encoder feedback from the servo at the 500PPR that we just configured. 



We are assigning the spindle to the RJ45 for the 5th axis on the C82 which uses pins 1 and 17 on port 1 for step and direction.

The Spindle Encoder and Index go to pins 2, 3, and 4 of port 2 as it is connected to the RJ45 on the C82 labeled as ENCODER.



The Step and Direction pins assigned to the spindle are mapped to Motor 5.


  • Configure/Control

Set the Motor Tuning for the Spindle.  Note that the steps per unit is 4 times the encoder count as the output is quadrature, so it needs 4 pulses per step. 



Set the Index Pulse function from the plugin in Mach4.


In the Spindle tab, set the maximum rpm of the spindle and check to enable step/dir spindle rigid tapping