I made a new motor pulley for the lathe to correct the basic 50Hz/60Hz issue. Now at 60.00Hz on the VFD spindle speed actually comes in a hair low, 965rpm which according to my calculation means if I raise the frequency limit on the VFD to 62.18Hz (it is a 60Hz rated motor) that should put it pretty much spot on 1000rpm. Then I can adjust the span and offsets on the VFD input and I should have it dead on across the entire speed range range. Progress...
------Original Mail------ From: "Peter C. Wallace" <p...@mesanet.com> To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> Sent: Thu, 18 Sep 2014 19:16:47 -0700 PDT Subject: Re: [Emc-users] New to LinuxCNC and PnCConf and need some help... On Thu, 18 Sep 2014, p...@wpnet.us wrote: > Date: Thu, 18 Sep 2014 19:29:43 -0500 > From: p...@wpnet.us > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: emc-users@lists.sourceforge.net > Subject: Re: [Emc-users] New to LinuxCNC and PnCConf and need some help... > > More fiddling and it appears the encoder is 2000 CPR. At any given speed > selection the spindle is turning a bit faster than specified, with the > difference becoming greater the higher the speed. I believe this is due to > it being a UK lathe and running at 60Hz instead of 50Hz, at least the > difference seems to match that ratio. As a result the spindle-at-speed is > staying false at all but the lowest speeds. I'm not sure of the best way to > deal with this, not using spindle at speed, setting the tolerance rather > high, something else? I seem to recall there was a parameter somewhere for > an analog output offset that I could perhaps use, or how can I run the > spindle closed loop and let linuxCNC hold the exact spindle speed? This is a analog output scaling issue so try setting the minlim, maxlim, scalemax parameters for the spindle to about 1.2x their present values. > > > ------------------------------------------------------------------------------ > Slashdot TV. Video for Nerds. Stuff that Matters. > http://pubads.g.doubleclick.net/gampad/clk?id=160591471&iu=/4140/ostg.clktrk > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Slashdot TV. Video for Nerds. Stuff that Matters. http://pubads.g.doubleclick.net/gampad/clk?id=160591471&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Slashdot TV. Video for Nerds. Stuff that Matters. http://pubads.g.doubleclick.net/gampad/clk?id=160591471&iu=/4140/ostg.clktrk _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
