On 7 November 2017 at 05:37, Gene Heskett <[email protected]> wrote:
> pid.N.command-deriv float in > The derivative of the desired (commanded) value for the > control loop. If no signal is connected then the derivative will be > estimated numerically. > > What for instance, would/should be connected here, and what would be the > desired result of such a connection? And in this context, what is a > derivative? "Derivative" means "rate of change". On a position servo loop you would connect the high-quality velocity output from an encoder counter or resolver here, or the analogue input value from tachometers. In your case this would be spindle accelleration, and you don't have any source of the signal that is a higher quality than the PID can calculate for itself, so leave it unconnected. > pid.N.error float out > The difference between command and feedback. > > This, on my G0704 seems to be a constant zero at any gain setting of the > halscope. What is this trying to tell me? It is telling you that the pid.N.command and pid.N.feedback are exactly equal, which probably means that you have wired the PID up wrong. -- atp "A motorcycle is a bicycle with a pandemonium attachment and is designed for the especial use of mechanical geniuses, daredevils and lunatics." — George Fitch, Atlanta Constitution Newspaper, 1916 ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
