The ABB SPBRC300​ is a high-performance Bridge Controller module designed for ABB’s Symphony™ Plus distributed control system (DCS). It functions as a critical communication gateway and processing unit within the Harmony/INFI 90 NET hierarchy. This controller enables seamless integration of legacy Symphony/INFI 90 I/O, third-party devices, and other network segments into the modern Symphony Plus environment, preserving existing investments while enabling system expansion and modernization.

A large power generation plant is undertaking a phased modernization of its ABB INFI 90 DCS to Symphony Plus. The turbine control and boiler management are upgraded to new S+ Controllers, but hundreds of field I/O points in the balance-of-plant systems (like cooling water and fuel handling) remain on reliable, existing INFI 90 I/O modules. The ABB SPBRC300​ Bridge Controller is installed as the strategic link. It resides in a new Harmony rack but connects directly to the legacy INFI 90 network (e.g., the Circle bus). The SPBRC300​ continuously polls the legacy I/O modules, acquires all process data, and makes it seamlessly available on the modern S+ network for the new controllers and operator workstations. Conversely, it passes commands from the new S+ controllers back to the legacy I/O. This allows the plant to modernize in stages without a “big bang” replacement, avoiding the enormous cost and risk of rewiring thousands of points. The SPBRC300​ directly solves the critical pain point of bridging technological generations within a live industrial plant.