Re: [CAD_CAM_EDM_DRO] servo controllers

J wrote:

>I have gained so much by learning from this group. I have my Taig mill converted to cnc and working nicely. This is all steppers, though, and I need to learn a little about servos. I have a Daihatsu lathe at work and the controller has died. I am interested in trying to use a pc-based controller to drive the Mitsubishi servo and spindle drives, but I'm not sure if this is really a good idea. Sorry if this is OT, but I would like to know what I need and whose websites to visit. What does it really take to "talk" to an industrial servo controller? Do I need these servo to go cards I hear about?
>
>

The first thing is to find out how the CNC control sent the
velocity command to the servo drive. The older ones used
+/- 10 V analog signals, with the voltage proportional to
velocity. Some newer drives use digital communications
protocols, some proprietary (bad news!) and some
"open" such as CANbus, fieldbus, etc. Some in the
middle-ages used PWM, some used step-direction.
If you have drives that accept step/direction signals, then
you can use almost any PC CNC program. (Not likely
in major machine tools.) For the many that use analog
velocity command, the Servo-to-Go can be used with EMC,
or my Pico Systems PPMC board set can do the same,
and a little more. One weak spot right now is that EMC
doesn't do lathe threading, so that could be a major stumbling
block.

Jon