Redundant Control and Communication for Power Control Systems

Reliable Power Control Systems (PCS) are essential for many facilities with mission-critical power needs, and reliable Programmable Logic Controllers (PLCs) and Input/Output (I/O) pathways are necessary for proper PCS function. This paper describes basic redundancy schemes for PLCs and I/O pathways


Single PLCs and I/O provide reliable service in power control systems. Nevertheless, redundant PLC and I/O equipment can be provided where facility uses require the highest levels of reliability. While Single PLC/Single I/O configurations are best for applications requiring the lowest costs, Redundant PLC/Single I/O and Redundant PLC/Redundant I/O configurations further improve reliability and availability. For the minority of facilities that require concurrent redundancy and maintainability, Quad-PLC/Redundant I/O configurations can be specified.