[Racer26]

Your cRIO definitely should be plugged into the fuseless (well, I believe its internal to the PD board, but that's irrelevant) 24V port. The sidecars, and breakout boards should be fed a 12V supply from one of the PD board's many other outputs, through a 20A Snap Action circuit breaker. Other than that, you should not be applying 12V to anything attached to the cRIO. I suspect you're referring to the Digital Sidecar (it attaches to the cRIO with a large DB-37 cable). It provides the familiar PWM outputs to connect to speed controllers. It should be fed 12V from a 20A circuit breaker.