safety

Hi

Most of the discussions on the list had been on how to do this/that
or how to do it better. But how about HOW TO DO IT SAFER. I don't see
much discussions on this?

Perhaps it is boring, but I think it is very important. For example,
many seem to be making their own power supply, but I think most will
just put a naked transformer, bridege rectifier, etc in the same box
as the other electronics. When I dismantle computer, independent disc
drive units, etc., I see that they put the power supply in a separate
box inside the main box itself (box-in-a-box). Is this good practice
for driver box or is it considered redundant?

What do most people on the list do from the safety aspect?

Thanks in advance

Lee

--- In CAD_CAM_EDM_DRO@y..., "paul_alz" <paul.w@a...> wrote:
> Having commercially manufactured a drive similar to this since
1986,
> see RS and Farnell catalogues, re: PVP2435, it still sells
amazingly
> well. So, as the designer I offer some additional tips.....
>
> When using phase chopping mode use the lowest Vf, highest current
> diodes you can afford. A lot of power is dumped and these diodes
can
> make toast for you ;-) Use maximum copper fill in this PCB area.
>
> Strongly suggest you limit the max rail to 40Vdc. Fast
deceleration
> rates with big inertia loads give rise to large back emf's. I've
> clocked them at +50V (outside L298 specs) which can produce some
nice
> pyrotechnics and bits of driver embedded in the opposite wall.
>
> Take care with your PCB layout and decoupling, the L297 can give
you
> some unsusual results.
>
> Good luck,
>
> Paul @ http://www.alzanti.com