SEL serves electric power utilities and industrial customers worldwide. Specifically, SEL designs and manufactures complete solutions for the protection, monitoring, control, automation, and metering of electric power systems. Our digital protective relays must respond to system faults, such as downed power lines caused by accidents or harsh weather, within milliseconds. SEL equipment serves hundreds of utilities and, in turn, millions of their customers by contributing to safer operations and by minimizing outages and damage caused by faults.

SEL introduced the first microprocessor-based protective relay in 1984, revolutionizing the power protection industry by offering fault-locating and other features for a fraction of the cost of earlier systems. Event reports in the relays allow engineers to analyze system faults. Innovative SEL communications technology enables customers to use the information in SEL and other substation products to monitor, control, and automate power system operation. SEL systems perform simple, inexpensive, and continuous monitoring of protection and automation information. Fault records and location, metering, status, and diagnostic equipment data are stored and reported. Information is used in substations, sent to control center applications, and made available for utility or third-party expert analysis. SEL also designs complete modular control houses for substations, provides engineering services, and serves the advanced training needs of industry professionals through SEL University. Courses emphasize the practical application of power system protection theory, concepts, and technology. 

Visit the SEL Press Room for more information.