Faults on overhead transmission lines cause transients that travel at the speed of light and propagate along the power line as traveling waves (TWs). One method of determining the fault location uses precise measures of the TW arrival times at both ends of the transmission line. Traveling wave fault locators built into transmission line protective relays and using standard CTs determine locations of faults to within a tower span or two, while adding very little cost. This webinar provides an overview of TWs and TW fault location capabilities in the SEL-411L and presents real-world field experiences using the SEL-411L.