Schweitzer Engineering Laboratories 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, SEL has grown and developed a complete line of products and services for the protection, monitoring, control, automation, and metering of electric power systems. SEL's 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. B&B Electronics has partnered with SEL to bring you a select offering of their ultra hardened products designed for your most rugged applications.