multi I/O relays needed

[ceencee]

I am thinking of building a controller for my cnc. It has a 29 head drill bank and other things that need switching on (horizontal drills, table pop up pins and a variety of others). One controller company said i may need 100 I/0 relays.How do you send that many signals from the computer using 1 port or will i have to put in more cards and ports to control all this? Is there a better way to control all these functions other than I/0 relays? Is their a schematic of a controller floating around the net which allows a person to plug in the parts that they require so the build will not be so complicated....im a cabinetmaker, not an electrician lol.

[Al_The_Man]

The usual way many I/O are handled is to use a PLC, there is a way incidentally to use Modbus with MachV1, I have never used this Modbus in Mach - MachCustomizeWiki
But the beauty of a PLC once you get to this many I/O is not only is the logic all handled in one unit but the I/O is conditioned, i.e. you can chose from different types of control from relay or SSR outputs and isolated inputs for sensors and switches etc.
Unfortunately you are probably not going to find anything off the shelf for your application and the logic will have to be written either way.
Al.