Re: 3 axis home and limit switches

--- In CAD_CAM_EDM_DRO@y..., "res0clvs" <rob.will@v...> wrote:

> Caudlet:
> There are five input pins... how do you connect nine switches to

these five

Some packages (MACH1) will allow you to define a second parallel port
(cheap add-in card) as well.

You need to have X+ X-; Y+ Y-; Z+ Z- and optionally seperate home
switches on each axis. You can use the limits as Home to save pin
counts or you may want to just have home on the X & Y. Using
individual switches the software should allow you to run to a limit
then job away from the limit rather than just shutting down the
machine. Of course you can always make the case that if you are
running a program and it runs to a limit it might as well stop
everything since something is wrong! I find that being able to jog
to a limit then do an offset has some advantages.

In the "If-You-Feel-Lucky" category: Use -limits (closest to 0,0,0)
only and define them as "home". Uses three pins and you have two
left for other inputs. One more idea. Do the three -limits and tie
the + limits in series over to a pin defined as e-stop. Sort of a
compromise.

I have been running my small engraving table with no limits but it
doesn't move that quickly and I watch every cut. The big 5' X 5'
table currently under construction that will have 160 to 200 IPM
rapids is another story and WILL have limits everywhere!