Schweitzer Engineering Laboratories, Inc. (SEL) has eliminated the time-consuming and costly tasks of calculating and testing protective relay settings from two-terminal line applications with the introduction of the SEL-387L Line Current Differential Relay. Requiring no settings, the SEL-387L Relay also eliminates the problems of misoperation due to erroneous settings and provides considerable savings on relay hardware costs. Using the proven restraint technology of the SEL-311L Relay, the new SEL-387L Relay provides secure, high-speed ground fault differential and sensitive phase protection that is not compromised by communication asymmetry, CT saturation, or different in-feeds.