The ABB Bailey INFI 90 remains a definitive Distributed Control System (DCS) platform, engineered for large-scale process automation in power generation and petrochemical industries. Evolving from the Network 90 architecture, the INFI 90 utilizes a high-speed, redundant communication loop (Infi-Net) and modular Harmony Control processors to execute complex regulatory and sequential control strategies. This series is distinguished by its robust multi-function processors, such as the BRC series, and high-density I/O modules that provide precise analog and digital signal processing with advanced onboard diagnostics. Designed for high availability and long-term lifecycle support, the INFI 90 environment facilitates seamless integration between human-machine interfaces and field-level instrumentation. For engineers maintaining legacy systems, sourcing genuine Bailey-branded spare parts—including bus interface modules, power mounting units, and specialized termination units—is critical for ensuring operational stability and preventing costly unplanned outages.