Re: [CAD_CAM_EDM_DRO] Re: The mechanical part of my router is done!

Hi Marvin,

Basically to protect from catastrophic failures. If the 5V regulator
fails, it takes out your PC! Motor power can be "dirty", and have very
nasty spikes on it. This is a harsh environment for a 5V regulator.
Better to use a separate, isolated winding on the transformer, or a
separate transformer.

In my last (just completed) driver/PS box, I used a little 5V switcher
supply that I got from a little in-line wall-wart box with a U.K.
connector on it. Two screws, it opened to reveal a little PCB. Removed
the cord and connector, and I had a nice little supply to mount in the
driver/PS box!

Alternate "free" supplies are the 5V from your PC. A scrap floppy drive
power connector will give you 5V from the PC's drive power connectors.
So will the joystick (game port), keyboard, and USB connectors.

Alan KM6VV


marvinstovall wrote:

>
> Alan, could you please elaborate on why we want the logic power
> isolated from the motor power?
> Thanks,
> Marvin
>
> --- In CAD_CAM_EDM_DRO@yahoogroups.com, Alan Marconett KM6VV
> <KM6VV@a...> wrote:
> > Hi Chuck,
> >
> > An interesting and very well made project! And as I have plenty of
> > stepper motors (I even have the same motors you used!), I'd be
> > interested in seeing plans for building it. Do you have plans ready
> > that you could post or email?
> >
> > For electrical hints, I'd suggest you keep the stepper wires away from
> > the digital wires, and be sure to have enough length to conveniently
> > reach your driver/PS. I have built a few driver/PS boxes, and just
> > finished and posted one in the SherlineCNC files (Schematic to be posted
> > in a day or two).
> >
> > Also an older one under photos "driver-P" of CCED.
> >
> >
> http://photos.groups.yahoo.com/group/cad_cam_edm_dro/lst?.dir=/Driver-
> PS+%26+Pendant&.src=gr&.order=&.view=t&.done=http%
> 3a//briefcase.yahoo.com/
> >
> > Ouch! Just look in photos for Driver-P
> > http://photos.groups.yahoo.com/group/CAD_CAM_EDM_DRO/lst
> >
> > My driver/PS boxes use Geckos, and one uses an early version of the
> > Gecko (CN0143). Microstepping works better on the newer steppers that
> > are designed for it.
> >
> > Be sure to put in line switch and fuse, grounded power cord, power entry
> > module (for the filtering), enable switches for each axis (where
> > possible), connectors for the stepper motors (makes trouble shooting
> > easier), DB25 connector for the parallel port, and a "power on"
> > indicator. Also desirable are SSS (solid state switches) for Spindle
> > (and AUX), individual fuses for each Gecko (be sure to put a 470 uF cap
> > at each module), Connectors for the limit switches, M6 "tool change",
> > and a digitizer.
> >
> > G201's need +5 from the PC, a wall-wart. Don't be tempted to hang a 5V
> > regulator chip on the motor's +48V supply! We WANT the isolation.
> >
> > HTH
> >
> > Alan KM6VV
> > SherlineCNC