RE: [CAD_CAM_EDM_DRO] Re: Chopper Transient Suppression

Hi Wayne,

You're probably just hearing the chopping frequency. Shouldn't be terribly
loud. Come over, and give a listen to mine! (Gecko drives, of course!).

Alan KM6VV

> <mariss92705@y...> wrote:
> >
> > .2uS is way to short. The motor winding capacitance results in
> > ringing (multiple cycles, underdamped envelope) for several
> > microseconds. We use a 5uS blanking period (comparator ignore time)
> > at the start of each switching cycle.
> >
> > Don't depend on the I-sense RC low-pass filter; blank it digitally.
>
> Mariss:
>
> Thanks. I cranked the blanking up to 4uS and the stepper motor
> vibration is now gone. The stepper motors still produce
> a high pitch screeching noise. Since I've never actually
> seen or heard anybody else's CNC machine to compare against,
> I have no idea whether my stepper noise is typical or excessive.
>
> Thanks for the prompt feedback.
>
> -Wayne
>