On Thu, 28 Apr 2016, Gene Heskett wrote: > Date: Thu, 28 Apr 2016 18:29:04 -0400 > From: Gene Heskett <ghesk...@wdtv.com> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: [Emc-users] New motor and driver in, runs w/o the springs, > at 10% of the big motors noise, but no faster. > > Greetings; > > I can do 48.7 IPM all day, either direction, but one cliock faster on the > jog speed, to 51 IPM and I have a following error in about 3/8" of > movement, independant of the direction. Next step up on the slider is > about 53.x IPM, gives a following error in about 3/16" of motion. > > The step timings are: > dir preset 6000 > Step_len 3000 > Step_space 3000 > dir hold, 6000 > > Worst case, 18 u-s to do a dir reverse and one step then revert the dir. > 12 u-s for dir_setup+dir_hold, and 6 more for the step=18. > > Grabbing a copy of kcalc, enter 18 as .000018, do a 1/x to get the max > freq=55,555.5555555555556 or a but over 55 kilohertz. Drive claims it > can do 200 kilohertz. driver is set for /8 microsrepping. Screw is a > 16x5mm. > > So how fast can it go when the pulses are at 200 KHz? > > FWIW, this tripping of the following error was taking place at the exact > same speed ( give or take a couple percent ) with the previous driver & > motor which was set for a /64, and the same step timeings and this one > is set /8, so no way can I convince myself the problem is the maximum > step rate the 5i25's stepgen can do, or that the driver can eat and be > happy. > > I have fiddled with the ini files maxvels, and maxaccels, without a > measureable effect.
Sounds like the stepgen maxvel or stepgen maxaccel settings are limiting you, so you are getting a following error. With 3/3 usec step timings you should get close to to 166 KHz. The stepgen maxaccel and stepgen maxvel parameters should be set to about 1.25X the machine acceleration and velocity limits If you have backlash compensation enabled, the stepgen maxaccel parameter must be set to about 2.5x the machine acceleration limit The 5I25 stepgens can do ~8 MHz step rate > > So where is the next place to look for my following error, which FWIW, is > at 48.7 IPM nothing but noise with the exponent never dropping below > +-EE-06 but mostly in the +-EE-12 range? > > Thanks all. > > 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> > > ------------------------------------------------------------------------------ > Find and fix application performance issues faster with Applications Manager > Applications Manager provides deep performance insights into multiple tiers of > your business applications. It resolves application problems quickly and > reduces your MTTR. Get your free trial! > https://ad.doubleclick.net/ddm/clk/302982198;130105516;z > _______________________________________________ > 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. ------------------------------------------------------------------------------ Find and fix application performance issues faster with Applications Manager Applications Manager provides deep performance insights into multiple tiers of your business applications. It resolves application problems quickly and reduces your MTTR. Get your free trial! https://ad.doubleclick.net/ddm/clk/302982198;130105516;z _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
