2012/12/30 Peter C. Wallace <p...@mesanet.com>: > >> >> Any ideas, why does pid output get saturated as soon as I try to jog >> the motor? I just retried and it is still the same. > > Too high acceleration?
I specially changed PID settings down to P=0.1 (from 4.9) and all the other parameters to 0 to make it really gentle. Acceleration already was set very low: 60 mm/s^2; for testing purposes I set it to 6 mm/s^2 (both default and max accel in [TRAJ] section of INI file) and it is still the same, so I think it is something else. 2012/12/30 Peter C. Wallace <p...@mesanet.com>: > > Also what is your servo thread period? with an 8 pole motor you may need 2 to > 4 KHz to avoid significant commutation phase lag Currently servo thread is running at default 1 kHz and I sometimes already receive realtime delay warnings. I set it to 2 kHz and went through the lead-angle check again. I set with 141, where there is little asymmetry - motor does not reach current limit in one direction and reaches 2940 RPM at value = -0.8 and 2530 RPM at value +0.8 and fault led starts to blink, when I go over +0.82...+0.83, but that is just bare motor and planetary reducer. I expect that in real machine these speeds might be little lower. Anyway, thanks for the advice, I do not really understand, how does servo period length affect this, but there certainly is considerable improvement after doubling servo-thread update rate. -- Viesturs If you can't fix it, you don't own it. http://www.ifixit.com/Manifesto ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. ON SALE this month only -- learn more at: http://p.sf.net/sfu/learnmore_123012 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
