Re: First CNC project

--- In CAD_CAM_EDM_DRO@yahoogroups.com, "treiman2001" <Tomr@c...>
wrote:

> Thanks Charles,
>
> I can tell that I still have a lot to learn. Things have changed

an

> awful lot since my Navy days working on a Sonar system that had

1200

> tubes and the power amplifiers were in water cooled cabinets.....
>
> I really appreciate the information.
>
> Do you know why some systems use a PLC between the PC and the

tool?

> Is it to control more I/O than can be accomplished with just the
> parallel port? Or is it a power thing to control a drive with

larger

> stepper/servo motors?
>

I have never heard of a PLC between the parallel port and a stepper,
but it seems that if you have lots of PLC's laying around, you could
use one as a stepper driver. kinda like using Windoz-XP to play
solitare.

There is a stepper driver that controls the stepper electrics. sends
pulsed signals to the motor coils, the driver monitors the current
and contorls it. check the archives for Xylotex and Gecko for more
info.

Dave