After passing this information on to the chief engineer, he has asked me to begin an upgrade replacement plan for the slc500. We have four Cat C-280 v12 engines that are each controlled by an HMI consisting of AB Panelview with SLC 5/04 and two Flex I/O racks. Two engines are for main propulsion, and two drive Kato 600v 3ph generators. The remote I/O's are mainly RTD and T/C modules that monitor engine and generator operation. The problem that occured was a shutdown from a generator bearing temp spike. All temps were normal and the only obvious failure indication was the flashing local fault LED on the 1794-ASB RIO module. We located a couple of new RIO modules and will keep the Flex I/O as a short term solution, but cannot chance catastrophic shutdowns due to unreliable monitoring equipment. I understand that we would have to replace the 5/04 with the 5/05, to utilize Enet, Cnet or Dnet. If we were to make this CPU upgrade, would it make sense to go ahead and replace the remote Flex I/O with SLC 500 chassis? Anyway, any advice or insight would be much appreciated!