On Wednesday 02 September 2015 05:56:56 Gene Heskett wrote: > On Wednesday 02 September 2015 04:50:24 andy pugh wrote: > > On 2 September 2015 at 03:05, Gene Heskett <[email protected]> wrote: > > >> You need the Limit3 _before_ the PID, not after. > > > > > > It IS in front of it Andy. > > > > That's odd then. > > > > So, you have > > motion.spindle-speed-out-rps => limit3.0.in > > limit3.0.out => pid.4.command ? > > > > I trust there _isn't_ a limit3 on the feedback to the PID? >[...] > I'd look right now, but that &^$ box has crashed. I have got to find a > better one. > > Thanks Andy. > > Cheers, Gene Heskett
Box rebooted. And I found when searching for the gearchange, that it was loadrt'd but never used! Nuked that line in the hal file. What pncconf did do was to setup a mux16, but only used 2 inputs. And as near as I can figure, its triggered automatically by pid.s.maxoutput. This is also used to correct the rpm request from motion that I get when I typoe s1000 m3 into the mdi command line, by dividing it by the gain setting input, the output of which goes into a "scale" module's gain control. I nuked all the gains in pid.s to zero except FF0, leaving that at 1.00, and started experimenting with the limit3 in front of the pid.s.command input. By diddling the mux16's in0 value I was able to get output speeds that except for speeds below 250 rpm are slowed by drive friction, and only about 50 revs or so high at a requested 2500. Then I started playing with the limit3's maxa. 500 still took 15 or so seconds to do a reverse, way too gentle. I finally wound up with its maxa set at 150000, which still gave a good turnaround time even from 2500 revs but was obviously gentler done. And no windup/overshoot at any tested speed down to 100 revs. The C7 lamp on the motor PSU brightens noticeably of course but the caps have about a 10% margin between actual and rated voltage. So now I go back out and see if I can stiffen its control up with some feedback as I can grab the spindle at 500 rpm and pull it down to about 275 with a bit of effort. This does seem like progress, but this mux16 gearchange bothers me, I get the impression it was intended to actually change gears on the fly, but I can't find such an output in this .hal file. It looks as if the drive gain is changed on the fly, perhaps by sensing that the head is in low gear from the maxerror output of the pid. Is there a tut in the wiki on this use of a mux16 for a gearchange? My search foo is weak. Thanks John, Andy and everybody else that can pipe up here. 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) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ Monitor Your Dynamic Infrastructure at Any Scale With Datadog! Get real-time metrics from all of your servers, apps and tools in one place. SourceForge users - Click here to start your Free Trial of Datadog now! http://pubads.g.doubleclick.net/gampad/clk?id=241902991&iu=/4140 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
