MACRO M20 for Spindle Positioning

Here’s the example of a spindle positioning macro. The macro is activated with “Q” parameter. For example, M20 Q100 sets a spindle to 100 degrees.

  M20 Macro for spindle positioning

Requirements:

• CSMIO/IP-S or CSMIO/IP-A controller
• CSMIO-ENC module
• a servo driver for spindle driving (step/dir for CSMIO/IP-S or +/-10V for CSMIO/IP-A )
• an encoder installed on a spindle or with ratio 1:1

1. Construction:

1. M20 macro for spindle positioning can only be used if the spindle is driven by a servo drive that works in position mode (never in opened position loop).
2. If there’s gear between a servo motor and a spindle, then it has to be non-slip gear, e.g. toothed belt used.
3. The encoder for revs and spindle angle reading must be installed directly on a spindle or through the non-slip gear (e.g. the tootled belt) , with ratio 1:1.
4. The encoder for revs and spindle angle reading can only be connected to CSMIO-ENC module.

The encode signals can’t be used for any other purposes as it will be overloaded this way (it’s a common issue).

1. Settings:

1. Using M20 macro for spindle positioning, you can’t use „Align at stop” function at the same time (plugin „Spindle” tab) and reversely.
2. If there is gear between a servo motor and a spindle, then the gear ration should be set in Mach3 in the „Spindle Pulleys” tab (1:1 by default).
3. Set the „Spindle Pulses / Revolution”  value in the plugin „Spindle” tab:

The „Spindle Pulses / Revolution” value is encoder pulses number incl. all four edges and the electronic gear in a servo drive (if used).

3. The M20 macro verifies the set and real position after spindle positioning.

If the difference between those two values is higher than „Const Offset = 1” parameter value, the „M20 ERROR Offset !!!„ error will appear.

The „Const Offset” value can be reasonably adjusted to our needs (the value of 1 is usually optimal).