Velocio PLCs, and power supply requirements

Anyone here have experience with Velocio PLCs here?

Currently looking at a Velocio Ace PLC. It's pretty cheap. Says it take 4.6 - 5V power supply. Now... is that a minimum requirement or limit? Can I use larger more common voltages like 24VDC? I must be blind, I can't find this information.

Thanks,

This page:
http://velocio.net/ace/

Shows 4.75 to 5.5 VDC and up to 300mA.

The I/O voltage specs are separate from the CPU power specs.

I have not used that PLC.