Re: [CAD_CAM_EDM_DRO] L298 goes boom on my camtronics :(

Hoyt,
You are quite wrong. Any inductance carrying current will generate large
voltages when disconnected as the flux field collapses. The "moving" is not
mechanical. It's magnetic. This is a basic electrical, natural fact of nature.
Touch the motor leads together where you can see them. A spark will be seen.
RichD

bjammin@... wrote:

>
> At 12:18 AM 8/4/02 -0400, RichD wrote:
> >Taus,
> >Arrrrrhhhhhhhgggg!
> >You broke rule number one!
> >NEVER disconnect stepper windings with drive power applied.
> >The high voltage back EMF is a killer to the IC's.
>
> Not at all. I've dis- and re-connected mine under power any number of
> times. There is no back EMF in a stepper that isn't moving. However,
> turning a stepper which isn't under power does turn it into a powerful
> pulse generator.
>
> Regards, Hoyt McKagen