Re: [CAD_CAM_EDM_DRO] Ferror & minferror

zbushz wrote:

>Well we finally got " the Beast" up and running under EMC2. The
>"Beast" is a Ramill VI, Big Iron, VIA mini computer, running Linux
>(BDI rc-46) Motenc-100 motion board driving brushless AC servos that
>has been in the works for sometime.
>It was running under EMC about a year ago... but we were plagued by
>following errors. I'm wondering if anyone has a good starting point
>for setting "ferror and minferror" in the *.ini file right now I
>have it set at
>ferror =0.100
>minferror = 0.01
>I just looked at the EMC Handbook and I don't really understand it...
>
>

First, these parameters have nothing to do with the servo performance,
they only set limits on when a following error will be declared.

Your values are QUITE high for a machine running in the Inch system.
(They might make a lot more sense in mm.) MIN_FERROR sets a lower
bound on the accceptable error. In this case, even at standstill, .01"
(or mm)
of error would be permitted. At 2 inches/second, the permitted error would
be 0.1 x 2 + .01 = 0.21

Are you controlling these Motenc drives with step pulses? I guess it
would be the EMC2 step generator. I'm not sure if increasing the
P term will help as with the EMC1 version.

Jon