Re: Stepper power supplies, unregulated and Zener selection

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
>