> From: Roland Jollivet [mailto:roland.jolli...@gmail.com] > On Fri, 19 Mar 2021 at 11:58, andy pugh <bodge...@gmail.com> wrote: > > > On Fri, 19 Mar 2021 at 01:46, John Dammeyer <jo...@autoartisans.com> > > wrote: > > > > > I take it then that you can't actually move the spindle to the index > > position unless you have some sort of control beyond velocity? > > <https://lists.sourceforge.net/lists/listinfo/emc-users> > > > My machine has a BT30 and an ATC. > The Fanuc AC spindle motor has no encoder, but there is an inductive sensor > on the spindle aligned for the ATC. > When you perform an M19 it spins a few times then stops on the sensor. (lit) > > I suspect it turns a few times and takes a 'snapshot' of the drive > waveform. It then simply applies that waveform to hold the spindle in the > correct position > On a M19, it holds the spindle quite firm if I try to rotate it by hand, > but have not tried to move it past the encoder. I suspect it will give an > error.. > > Roland Hi Roland, Thanks for that feedback. Interesting.
My AC Servo is currently running PWM with a small PWM to 10V module from China. I'm limited to about 100RPM which is till 290RPM lower than it was with single phase and 2HP running belt reduction. Once I rewire to the second parallel port I'll have step/dir and I'll add an encoder with index. At the moment I'm still trying to keep the system portable between MACH3 and LinuxCNC and although MACH is clever enough to be able to check a box and change the STEP output to PWM using the same Direction pin unfortunately to do this with the MESA board would require new software and reprogramming the MESA each time the system booted to the other OS. That's why at the moment I'm running PWM. But then I don’t think MACH3 can do absolute positioning of the spindle so for the moment step/dir is on hold. Plus I'm using TT type tool holders so rotary position isn't super important. I'm swinging more and more to probably never again booting the system with WIN-XP and MACH3 although I must admit the built in wizards for MACH3 are sure handy. John _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
