On Thu, 2008-11-06 at 22:56 -0500, Alpha wrote: ... snip > I want to pull the control off the machine and install a P.C. with EMC. > So I am looking for a bit of guidance. > > I now have a machine tool, with a control, plc, servo drivers, servos, > encoders, limits switches and nice ball screws. > > From what I understand after reading for a few days. I need a control, > a driver card? with i/o plus everything above except the plc?
EMC2 has PLC features built-in or can interface with a stand-alone PLC. You will need to develop a custom EMC2 configuration to do this, which is covered in the Integrator's Manual. http://www.linuxcnc.org/docs/EMC2_Integrator_Manual.pdf You will need to find out what your servo drivers need for input. Some need a digital step pulse and direction signal similar to a stepper driver. Others need an analog signal generally + or - 10 Volts or 5 Volts or 0 to 10 Volts plus one or more direction signals. Another common driver needs a PWM (Pulse Width Modulation) plus direction signals. You will need documentation or study the wiring to get an idea of what you have. EMC2 outputs are generally digital (0 and 5 Volt signal states) which covers on/off control. PWM is similar except that the on/off states are rapid and the percentage of on time relative to off time represents an analog or numerical value. If you need analog outputs you will need to convert a PWM signal, use a DAC or similar device, or get a controller with analog outputs or option card. > Which driver card is better with EMC? It depends on the hardware that you will be using. > > Do I use the same card to drive the spindle and all the axis (including > the tool changer)? It's possible, but it depends. It is common to have a VFD (Variable Frequency Drive) driving a three-phase spindle motor. These usually need an analog voltage input and one or more digital inputs to control direction, enable, etc. The Pico Systems controllers I have used use PWM to drive the axes and then have an option card added for the VFD analog signal. > Is there a all in one card for the servos and the encoders? Is it the > way to go? Generally, controller cards have encoder inputs along with the servo outputs. For a servo step/direction controller, the encoder data is used by the controller to locate the "steps". You can route the encoder data to EMC2, but it is just for position display purposes. EMC2's claim to fame is that it _is_ a motion controller, so you don't need to have an external controller, but a driver. In this case the "controller" card is an interface that passes encoder information to EMC2, which then calculates an appropriate output. > Thank you for reading > > Jeff Thompson. A Kitamura/EMC2 conversion will not be a trivial pursuit. It will take allot of time and study to get it completed and sorted out, but I have little doubt that EMC2 is up to the task. The more information (specifications, pictures, configuration file listings) you can provide, the easier it will be for those on this list to help. ~~~~~~~~~~~~~ Kirk http://wallacecompany.com/machine_shop/index.html ~~~~~~~~~~~~~ ------------------------------------------------------------------------- This SF.Net email is sponsored by the Moblin Your Move Developer's challenge Build the coolest Linux based applications with Moblin SDK & win great prizes Grand prize is a trip for two to an Open Source event anywhere in the world http://moblin-contest.org/redirect.php?banner_id=100&url=/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
