Apply the SEL-411L Relay for complete protection and control of any transmission line. The SEL-411L provides differential protection with both phase- and sequence-based operating elements for sensitivity and high-speed operation.

Apply the SEL-421 Protection, Automation, and Control System for high-speed distance and directional protection and complete control of a two-breaker bay. Protect any transmission line using a combination of five zones of phase- and ground-distance and directional overcurrent elements.