Will this isn't really a Vital Systems issue, it's a me trying to figure out how to wire this issue

I will try to explain how I have this hooked up better

I have my switches (INPUTS) ran to OPTO 22 relays (G4IDC5, that's 10-30v in and 5v ttl out), and I get the power for the switches from the machines 24vdc power supply. From there they enter the motion control card (via 5v ttl).
The encoder (MPG handwheel) is a single-end (A,B) encoder. I have purchased an encoder converter from US Digital that converts the single-end to a differential signal (A+/-, B+/-).
The handwheel itself is integrated (meaning that the encoder (MPG) and the switches are on one card within the handwheel). In the wiring diagram (all in Japaneses) I can see that the switches share a COM. I have hooked 24vdc to that COM for the switches. When the switches are turned they make contact and send 24vdc to my OPTO relay which in turn forces the relay to send the proper 5vdc TTL to the motion control card triggering the INPUT in Mach3.
My question is since the switches and the MPG are integrated inside the handwheel should I be sending 24vdc through the switches? Should I try to lower the voltage or revers the polarity and make the switch go to ground to trigger the relay instead of sending the 24vdc from the switch to the relay?
Thanks
