In this scenario, the customer has an N2-based BAS and has previously replaced legacy N2 controllers with N2-configured FX-PC controllers as a part of an earlier replacement scenario. Now the customer is contemplating future risk and the cost and disruption of more legacy N2 controller replacements.
Option 1: You should consider modernizing the BAS to use BACnet MS/TP protocol. This option requires replacing the N2 supervisor with a BACnet supervisor, switching the existing N2-configured FX-PC controllers to BACnet, and replacing the remaining legacy N2 controllers with BACnet-configured FX-PC controllers.
Note: If the existing N2 supervisor also supports managing BACnet MS/TP networks, then the supervisor may not need to be replaced. See Converting to BACnet MS/TP field bus for the key challenges to this option.