Honeywell 900S75S - 0460 I / O Scanner 2 - Port SIL CONTROLEDGE PLC The I/O Scanner 2 module resides in a remote I/O rack along with its I/O in a Redundant Controller System. The Scanner 2 has two I/O connections I/O A is connected to CPU-A and I/O B is connected to CPU-B in the Redundant Controller rack. The scanner 2 collects data from the Input modules populated in its remote rack and communicates the information to the Lead controller. Output data is sent from the Lead