Key Concepts in Industrial Protection Relay Networks

Protective relays at industrial facilities are interconnected (or networked) in a wide variety of ways, for many different purposes. The intended uses of the network and the nature of the protected system must determine the way in which the network is implemented. While industrial networks have some commonality with networks at transmission and distribution utilities, there are also differences necessitating an industry-specific approach. This paper will review the different purposes of protective relay networks and provide an overview of network architecture and implementation issues. Various protocols and architectures will be reviewed with attention to their capabilities for tasks important for an industrial site such as transfer tripping, arc flash incident energy reduction, alarm and status monitoring, and data logging. References to existing papers and standards will be provided to the extent that they are useful for an industrial facility.