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Underground Secondary/Low-Voltage Reset Fault Indicator

  • Line-powered arm and reset eliminate the need for a battery.
  • The secondary voltage supplies the necessary arm and reset requirements in applications where there is insufficient load current to use an SEL-SR.
  • The SEL-SR works for single- and three-phase applications.
  • BEACON LED, target, and combination display options are available, depending on your application and operating practices.
  • The reset restraint option prevents undesired reset from backfeed voltage. Please consult SEL.

Accessories and Tools for Fault Indicators and Sensors

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Pad-Mounted Transformers With Low Primary Voltage—Apply SEL-SRs to pad-mounted transformers when there is insufficient primary voltage to power and reset voltage-powered fault indicators.

Pad-Mounted Transformers Without Capacitive Test Points—Install the SEL-SR in pad-mounted transformer applications without capacitive test points and where there is insufficient primary load current to power a current-powered fault indicator.

Daily Changes in Load Current—Monitor residential single-phase transformers with the SEL-SR. The SEL-SR’s ability to power from secondary voltage ensures it will detect faults during lightly loaded circuit conditions. Circuits feeding residential areas with daily changing load currents may see a significant drop in load current as home owners leave for work or go to sleep late at night. In some cases, circuit loading can drop to levels below the minimum current requirement of most faulted circuit indicators.

Seasonal Changes in Load Current—Install the SEL-SR on circuits feeding areas with seasonal changes in load, such as school campuses and resorts. These circuits may see little to almost no load while the facility is not being occupied. Since faults can still occur on these circuits, the SEL-SR will help identify the fault location, allowing crews to repair the circuit and ensure it is operational in time for the next season.


  • Tamperproof bolt display
  • BEACON bolt display
  • Standard “V” display
  • Large “L” display
  • Integral display

The Firmware IDs for older versions of the firmware can typically be found in Appendix A of the instruction manual.