Re: FS: New 4 axis microstepping driver $45.00 USD

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "jeffalanp" <xylotex@h...>
wrote:

> Fred wrote:
>
> >A 24 volt ac transformer is just
> > about right for a power source (plus a bridge and a capacitor).
> > These transformers are readily available in 2-4 amps and

contribute

> > to a very inexpensive solution for a do it yourself project.
>
> Please be aware that 24VAC when filtered and rectified becomes
> about 34VDC. If the transformer were rated for 110VAC to produce
> 24VAC, and you used 115VAC or 120VAC (like I have), then you would
> surpass the 35VDC *absolute maximum* limit of the A3977SED driver
> chip.

Jeff,

I agree whole heartedly. If local line voltage exceeds 120, it is
probably a good idea to consider a step down transformer for any CNC
equipment, this is very common practice on commercial machinery. I
would also recommend a UPS type setup on your computers as a UPS will
usually have some voltage regulation to maintain supply voltage
within a narrow range. Surge protectors at a minimum.

It's a good idea not to exceed the manufacturers limits on any
electrical equipment.

> On Wednesday, Mar 17, 2004, at 17:40 US/Eastern, Fred Smith wrote:
> >> --- In CAD_CAM_EDM_DRO@yahoogroups.com, "Fred Smith"

<imserv@v... wrote:

> >>>> We have a limited edition, 4 axis, microstepping driver

available.Based

> >>> on
> >>>> the Allegro A3977 chip. The board is rated at 2 amps per axis
> > and
> >>>> maximum of 35vdc. This is a promotional item and is subject to
> >>> prior
> >>>> sale. Quantities are very limited.
> >
> > Info at: http://www.cadcamcadcam.com