Re: Stepper power supplies, unregulated and Zener selection

Hi,

Good point.

It's always a good idea to 'scope the power supply while gradually
increasing the rate of deceleration. If the supply voltage starts
nearing the limits, take the corrective measures.

Mariss

--- In CAD_CAM_EDM_DRO@egroups.com, "Wally K" <cnc4me@u...> wrote:
> Mariss, thanks for reply. The 5w zener suprised me i thought the
> energy dumped by large motors would be substancial.
>
> Also want to go over 1 point of yours of only 1 drive per supply.
> Most people have 3 drives per supply. And what if all 3 motors
> decelerate at the same time.
>
>
> Wally K.
>
>
> --- In CAD_CAM_EDM_DRO@egroups.com, "Mariss Freimanis"
> <geckohall@h...> wrote:
> > Hi,
> >
> > Wally, a 5W zener should do. The amount of energy returned is not
> > that great. Make sure the zener voltage is higher than the
maximum
> > possible power supply voltage though. Do not use a series
resistor.
> >
> > Again, this is a concern only if ALL of the following apply:
> >
> > 1) Only one drive per supply
> > 2) Large inertial load
> > 3) High speed
> > 4) Very rapid deceleration
> > 5) Power supply voltage near 80VDC
> >
> > You might want to look at the "Enery Dump Circuit" in
> the "Circuits"
> > file in the "Files" section of this group. This circuit senses
> > current direction and will dump returned energy to ground.
> >
> > Mariss
> >