On Sunday 31 August 2014 04:54:26 Andy Pugh did opine And Gene did reply: > > On 31 Aug 2014, at 06:19, Gene Heskett <[email protected]> wrote: > > > > Bringing up the Igain > > had the effect of slowing it quite drastically. Running at 500 revs, > > with Igain at the default .1, raise it to 10 and it slows to about > > 125 rpms. > > If adding I gain increases the orator then something is very wrong > indeed. > > Is your measured spindle velocity actually positive in the positive > motor direction? Are you consistent in the RPS and RPM domains? > > The encoder velocity is RPS and there is a matching HAL spindle output
Those are the two outputs I am using, and IIRC the only scaling there is an *60 to get the tach reading for the screen display into rpms. If I type an s1200 in the mdi cli, its 20 at the motion modules rps output. That however is about 25 rpms more than it can do on the voltage available. The 5i25 pwmgen has no pin to set the max duty cycle, so it must be controlled by setting the PID maximum output to 1 or 2% less than its value. I will add a mul2 into that setp path if I can figure out a way today. setp's normally execute only at startup. So the question then becomes "can hal do math in its init code?" I've not seen that done so the only way is to try & fail if it cannot. :) On another front, Peter says I am running the encoder sample frequency to high, something I have not yet had a chance to experiment with and which I arbitrarily set at 2mhz. He says a lower value there will likely reduce the edge to edge noise output of the encoder. So that is yet another experimental point to cover today. I'll make it match the pwm_frequency just for grins. I will post the solution if I can determine why the attained speed is so wildly effected by the Igain. Thanks Andy. > ----------------------------------------------------------------------- > ------- Slashdot TV. > Video for Nerds. Stuff that matters. > http://tv.slashdot.org/ > _______________________________________________ > 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) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Slashdot TV. Video for Nerds. Stuff that matters. http://tv.slashdot.org/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
