Schweitzer Engineering Laboratories (SEL) | 276,268 followers on LinkedIn. Making Electric Power Safer, More Reliable, and More Economical | SEL is a globally recognized designer and manufacturer of products and solutions that make electric power safer, more reliable, and more economical. Legacy Over forty years after introducing the first digital protective relay, our devices, software, and systems are found in 173 countries around the world. Customer Focus From our headquarters in Pullman, Washington, we partner with public utilities and private industry all over the world to offer the industry’s top, 10-year warranty and no-cost technical support for as long as our products remain in service.