On Tuesday 09 July 2013 13:56:33 Jon Elson did opine: > Gene Heskett wrote: > > To continue this thread, I went out and whacked at the hal file, > > converting the limit2 module that was controlling the rate of rise > > and fall of the requested spindle speed, to a lowpass module. > > > > Setup with a gain of 0.005, and with an s1000m3 in effect, typing an > > m4 initiates the reversal, it takes about 2.5 seconds or a hair more > > to stop, then the same rpms are achieved in reverse in maybe 1.25 > > seconds. So the difference is nothing short of amazing because with > > the limit module, it took 2.5 to 3 seconds to get back up to speed, > > with cabinet shaking jerks at the beginning of the acceleration. My > > guess is that the jerk has been reduced by a noticeable amount. > > Hah! So, I was right to use the lowpass function when I set up rigid > tapping > on my mill! Several people told me to use limit, but I never went back > to change it, as the lowpass version seemed to work fine. I guess > ignorance is bliss, some of the time! > > Jon
Chuckle. Yup, makes me feel pretty good when I actually hit a lick that works. I didn't run my loop code for peck tapping using g33.1 yet as I suspect I had better find a higher power handling method of stopping the motor in an equal amount of time. One run pushing air, and using the limit2 gets the existing 80 watt kludge almost uncomfortably hot. I am considering trying to design a switch mode load, to hold about a 10 amp draw during the stop. But I don't know as any of the chip makers has cobbled up a suitable driver IC. In that event, it might also be best to put the lowpass into the initial braking application to reduce the initial jerk there too. But if I do that, the switch mode stuff itself will run reasonably cool, so where does the heat actually go? Its got to go someplace, I just haven't thought it through. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! My views <http://www.armchairpatriot.com/What%20Has%20America%20Become.shtml> I want you to MEMORIZE the collected poems of EDNA ST VINCENT MILLAY ... BACKWARDS!! A pen in the hand of this president is far more dangerous than 200 million guns in the hands of law-abiding citizens. ------------------------------------------------------------------------------ See everything from the browser to the database with AppDynamics Get end-to-end visibility with application monitoring from AppDynamics Isolate bottlenecks and diagnose root cause in seconds. Start your free trial of AppDynamics Pro today! http://pubads.g.doubleclick.net/gampad/clk?id=48808831&iu=/4140/ostg.clktrk _______________________________________________ Emc-developers mailing list Emc-developers@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-developers
