speed protection relay / digital / programmable / configurable
SEL-T400L Schweitzer Engineering Laboratories



  • Measured/monitored value:


  • Other characteristics:

    digital, programmable, configurable, multifunction, transmission line


Time-Domain Line Protection
Apply the SEL-T400L Relay for ultra-high-speed and secure protection of critical lines. With breakthrough time-domain technologies, the SEL-T400L securely trips in as fast as 1 millisecond, records events with sampling up to 1 MHz, and detects faults accurately to the nearest tower with single- and double-ended traveling wave fault locators. The SEL-T400L Relay complements your traditional protection and gives you speed.