current protection relay / digital / programmable / configurable
SEL-311L Schweitzer Engineering Laboratories



  • Measured/monitored value:


  • Other characteristics:

    digital, programmable, configurable, multifunction, transmission line


Line Current Differential Protection and Automation System
Use the SEL-311L Line Current Differential Relay with integral four-zone distance backup for easy-to-apply, high-speed line protection.

Apply subcycle current differential protection with included four-zone distance and directional overcurrent backup. Use single or dual differential channels for reliability. Apply the SEL-311L on two- or three-terminal lines. Unique measuring elements provide coordination with tapped loads. Reduce total project construction and operation costs through integration of the included four-shot recloser and relay logic operators into your automation system.

Improve protection system reliability with continuous checks of communications quality, breaker wear, battery voltage, and relay health. Use the included LCD display in place of traditional panel meters.