Re: High voltage protection for a breakout board.

Hi Arturo,

I don't know if you realize that optoisolators are not simply used
to "protect the computer from high voltages that stepper drivers
handle." Your original post also seemed to show a bit of a
misunderstanding in this area as you were thinking a simple 74xx245
buffer might be a replacement for an optoisolator because of its 2kV
ESD protection. As I said, ESD is a minor consideration and has
really has nothing to do with protecting the computer from anything
going on with the motor. It has more to do with static discharge as
what happens under low humidity conditions when someone walks across a
carpet and decides to touch an exposed electronic connection.

At the risk of repeating myself (please take this as constructive
criticism), optoisolators are very useful for separating circuits
entirely--include grounds. Sans an optoisolator, you risk making for
an unreliable system if you join a digital signal ground with a noisey
analog ground that potentially could also create ground loops. Even
if you manage to have a system work on your workbench, you are only
asking for trouble if you expect any arbitrary wiring or driver a
potential user could use would work without intermittent/hard-to-find
problems.

Cheers,
Adrian

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "Arturo E. Duncan"
<aduncan@c...> wrote:

> Alan,
>
> Opto-Isolation is to protect the computer from the extreme high
> voltages stepper drivers handle(yes, I know geckos have opto-
> isolators, there are other drivers that don´t).
>
> I understand your opinion with regards to breakout boards. I myself
> have setup machines without them. But it makes things easier and
> safer to setup. This breakout board I hope to price it the 20 to 30
> range, making it affordable to any budget.
>
> Thanks,
>
> Arturo Duncan