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« on: September 12, 2018, 04:46:22 PM »
If you are running a Galil controller with servo motors, Mach3 is supposed to work differently from what it does with steppers. If you do not have a Galil controller, then you may have posted on the wrong forum. To quote Smurf:
"Mach3 with a Galil is not the same as Mach3 controlling a stepper system. Mach3/Galil is a closed loop system! The servo PID loop is closed on the Galil. And there is another important distinction; Mach3 gets its position from the Galil!!! This is in contrast to a stepper system where Mach3 has it's own notion of where it thinks the table should be. What is displayed in the Mach3 DROs comes from the Galil (which comes from the encoders). This can be verified by disabling the servo drives and turning the motors by hand. You will see the position updated in the Mach axis DROs."
The Galil controller is supposed to handle the motion, as I understand, and Mach3 communicates with SmartTerminal. Unfortunately there seems to be a bug in ver 4.6 of the Galil-ST plugin that handles moves as if you had stepper motors, i.e. running open loop. Ver 4.4 seems to work correctly in this regard, but may have other issues.
To test if you have the problem, Reset Mach3 and turn one of your motors by hand. You should see the DRO update as you turn it. Another test is to turn off the power to your servo motors, or disconnect the cable from power supply to controller if you can. Then send a midi command G1 X1 F30 from Mach3. The motor cannot move since the power is off, so the encoder cannot move either. If you see the DRO changing as if it is moving, then you have an open loop, not what it should be. I have observed both of these problems with my system using ver 4.6.