SEL introduced the world’s first digital relay in 1984, revolutionizing the power protection industry by offering fault locating and other features for a fraction of the cost of earlier systems. In the years since, we have grown and developed a complete line of products and services for the protection, monitoring, control, automation, and metering of electric power systems.

Creativity, extensive research, attention to customer needs, and a wealth of power system, automation, communications, and cybersecurity expertise drive our research and development processes. Our multidisciplinary teams of power, communications, automation, software, mechanical, and electronic design engineers develop products that meet or exceed customer needs for features, functionality, and robustness.