I believe the DMM drives accept step/dir inputs so you are correct that would be the way to go for him
Quote Originally Posted by mactec54 View Post
Active low and active high is normally just a direction change to run a servo like this you need a +/- 10v the normal PWM will only be 0-10v so if this is what you have it will not work

So unless there control says it can do analog +10v -10v output it is not going to work and you will have to use Step/Dir to control the spindle