On Thursday 30 April 2020 20:35:55 Leonardo Marsaglia wrote: > > Great, but from what to what, so the fix becomes part of the list > > archive? > > I started using *spindle.M.speed−cmd−rps *and it worked ok until I > tried G96. Three hours later I found that I needed to use > *spindle.M.speed−out−rps*. > > I don't know if this should be fixed because it's meant to be used > when the spindle works with a gearbox as Andy kindly pointed. What it > should be done is to specify that out in the manuals. The main > difference is *spindle.M.speed−cmd−rps* doesn't account for spindle > overrides while *spindle.M.speed−out−rps > *does. > Kewl, and we even get an explanation too. Msg marked. Thank you Leonardo. > > El jue., 30 abr. 2020 a las 20:54, Gene Heskett > (<[email protected]>) > > escribió: > > On Thursday 30 April 2020 19:25:16 Leonardo Marsaglia wrote: > > > > However if that Yaskawa actually is counting steps, something > > > > I've never ever seen one of the clones I am using do, then you > > > > are probably just sending too many steps/second. I could be > > > > wrong, as its not impossible, but I'm thinking you may have > > > > miss-read the Chinglesh in the manual. But do check the polarity > > > > of the signal as it arrives at the vfd. In that event, > > > > switching to a pwmgen, running in pdm mode, may be the fix you > > > > need. > > > > > > Indeed it sounded strange to me too, and when we purchased the > > > boards to make the conversion we planned to drive the VFD with > > > analog voltage like usual but when I discovered that feature a few > > > months ago I decided to give it a try and save a 7i33 for later. > > > It's working pretty well now and I tuned it better today. It > > > accepts frequencies from 0.5 khz to 32 khz. We are peaking it at > > > about 24000 khz but the problem I had was the step lenght was to > > > low for the driver to "see" the pulses. Now I only need to filter > > > the encoder from the spindle to get rid of that noisy output wich > > > is not hurting anything but it would look better filtered. > > > > I've had that noise come back thru the servo driver strong enough to > > hammer the backlash and make it sound like all the ball bearings in > > the mills head had suddenly worn square. A higher res encoder > > stopped all that noise. I can also run 10x the Pgain w/o any > > instability. Sweet! > > > > > On other thing, css is scaled from x=0, if its not 0 as touched > > > off at > > > > > > > the exact center of the workpiece, then css is going to be > > > > miss-applied. It does have gotcha's in that regard. > > > > > > Yes, I double checked that today and it was ok. My problem was > > > the output source of the commanded velocity for the spindle. I > > > spent almost 3 hours trying to figure out what was the problem and > > > all it took to solve it was to change a signal name in the hal > > > file :(. > > > > Great, but from what to what, so the fix becomes part of the list > > archive? > > > > > El jue., 30 abr. 2020 a las 14:41, Gene Heskett > > > (<[email protected]>) > > > > > > escribió: > > > > On Thursday 30 April 2020 12:36:00 Leonardo Marsaglia wrote: > > > > > Just to be super clear. I'm sending the spindle speed cmd > > > > > velocity to a step generator in velocity mode. Could this be > > > > > the source of the problem? Or does LCNC internally set the > > > > > speed of the spindle based on the X diameter? > > > > > > > > I must say thats an unconventional mode to me. I know nothing > > > > about your Yaskawa, but as a CET, one thought keeps running thru > > > > my mind. Most vfd's will do a decent job of averaging a digital > > > > command signal, giving about 50% speed for a signal thats high > > > > 50% of the time. We often set steppers up for a true=logic low, > > > > and feed the + line of the driver at 5 volts, and the step > > > > signal to the corresponding - terminal at the driver input. > > > > > > > > primarily because our interface electronics can sink lots more > > > > current in the logic low state than they can source in the logic > > > > high state, its the nature of TTL circuitry and the capability > > > > ratio can be 10/1. So an output that can sink 24 mills is a much > > > > better opto driver than one that can only source 2.4 milliamps. > > > > If you feed that "inverted" signal into most vfd's, they would > > > > interpret that 98% of the time logic high which you are sending > > > > it for a low speed command, the vfd will treat it as if its a > > > > high 98% of the time resulting in a high speed command actually > > > > being done. You should be able to verify that with the > > > > halscope. Or most any scope with sufficient bandwidth to show > > > > the steps as a well squared wave. If you are seeing a triangular > > > > wave, the scope isn't fast enough. > > > > > > > > However if that Yaskawa actually is counting steps, something > > > > I've never ever seen one of the clones I am using do, then you > > > > are probably just sending too many steps/second. I could be > > > > wrong, as its not impossible, but I'm thinking you may have > > > > miss-read the Chinglesh in the manual. But do check the polarity > > > > of the signal as it arrives at the vfd. In that event, > > > > switching to a pwmgen, running in pdm mode, may be the fix you > > > > need. > > > > > > > > On other thing, css is scaled from x=0, if its not 0 as touched > > > > off at the exact center of the workpiece, then css is going to > > > > be miss-applied. It does have gotcha's in that regard. > > > > [...] > > > > > > > > Cheers, Gene Heskett > > > > -- > > > > "There are four boxes to be used in defense of liberty: > > > > soap, ballot, jury, and ammo. Please use in that order." > > > > -Ed Howdershelt (Author) > > > > If we desire respect for the law, we must first make the law > > > > respectable. - Louis D. Brandeis > > > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > > > > > > > _______________________________________________ > > > > Emc-users mailing list > > > > [email protected] > > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > > Emc-users mailing list > > > [email protected] > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > Cheers, Gene Heskett > > -- > > "There are four boxes to be used in defense of liberty: > > soap, ballot, jury, and ammo. Please use in that order." > > -Ed Howdershelt (Author) > > If we desire respect for the law, we must first make the law > > respectable. - Louis D. Brandeis > > Genes Web page <http://geneslinuxbox.net:6309/gene> > > > > > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users
Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) If we desire respect for the law, we must first make the law respectable. - Louis D. Brandeis Genes Web page <http://geneslinuxbox.net:6309/gene> _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
