Hi Tom

Hopefully the last Question regarding this build as almost everything is functioning perfectly

i have configured my VFD servo Drive as an axis with DAC 0-10v control and is all working through Kanalog board and direction is controlled through a latching relay

The Machine spindle is belt driven from the servo motor and has a disk on the spindle with 50 holes around it , onto which is mounted a slotted opto switch (RS stock Number 306-061) , the output is an npn photo transistor .
Is it possible to use this for speed measurement for the spindle ? and could you point me to an article to set up the speed measuring function

Regards

Sean