Mb2hal speed irregular timing of reversing of spindle

Can you explain in more detail how to run linux from comand prompt . I tried opening terminal and running linux cnc from there but didnt get any error log messages.

I changed serial delay to 10ms this made it faster and more consistant but i think im still geting modbus errors.

Overtravel rigid tapping can be upto 8mm at 600 rpm due to the delay. Crashing tools.

just type linuxcnc in a terminal window. The error messges are just printed to the console in that window, not to an error log.

Thanks go it to work. Was using a shortcut to linuxcnc.

With some testing update rate is 6hz. And no errors idle.

I think i might be losing data from interference. Possible reason for random timing behaviour.
I dont have terminating resistors at the vfd. So i will work on this and see if things change. No oscilloscope to test.

All fixed and running very nice! Main problem was data com errors caused by vfd noise.

Grounding the 485 cable at the serial converter on the pc fixed all the errors. Grounding the cable at the vfd had little to noneffect. I used cat 6 sheilded cable 3m length with no terminating resistors.

Response is 10hz and repeatable timing plenty fast enough for rigid tapping spindle control.

Thanks for all the directions to fix the problems.

Glad to hear you were able to sort it out. I wish simply running a shielded cable and grounding it on one end had fixed my com errors, but no luck for me.

Could try a diffrent 485 converter. I grounded my sheilding to my converter ground terminal.

Do you get comm errors with the vfd not puting out any frequency. I could see more errors increasing as inverter turned on.

You can decrease carrier frequency of inverter also to limit the emf from the vfd.