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Overhead Wireless Sensor

Apply the SEL-WSO to improve distribution system reliability by remotely monitoring circuits for faults and outages. Using centrally reported data, you can dispatch line workers directly to the faulted line section, reducing outage durations by 50 percent or more. You can also periodically log circuit load data for system analysis and monitor your distribution system from a central location.

Accessories and Tools for Fault Indicators and Sensors

Starting At

$714 USD

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Remote Fault Monitoring—Receive wireless indication of fault status from the SEL-WSO to pinpoint the fault location before dispatching troubleshooting crews. The SEL-WSO uses the AutoRANGER trip logic for simple integration with existing protection schemes. After detecting a fault, the SEL-WSO alerts personnel of the affected area with an exception fault report.

Outage Indication—Identify de-energized sections of the circuit with exception outage reports. After the outage, the SEL-WSO automatically sends a restoration report indicating when the line section is re-energized.

Feeder Reconfiguration—Install near remote-controlled, motor-operated switches to provide information for feeder reconfiguration.

Momentary Event Detection—Detect momentary faults, momentary outages, disturbance events, and load pickup events to improve system reliability.

Load Monitor—Approximate circuit loading with average or peak load data refreshed every 24 hours.


WSO CalloutsWSO Diagram


How To Install WSO-10 & WSO-11 Overhead Wireless Sensors

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How To Install WSO-10 & WSO-11 Overhead Wireless Sensors
  • Installs with a hot stick and includes magnet tool activation and a local display.
  • Saves time by letting you activate, install, and confirm operation within 5 minutes.
  • Monitors load current, trip threshold, battery status, and history of outages and surge events.
  • Allows more efficient maintenance scheduling using stored data profiles.
  • Prevents false tripping with the inrush restraint feature, which allows for coordinated integration with automated reclosing schemes.
  • Displays a visual target in addition to remote indication via a 2.4 GHz wireless system (Trilliant RPMA network).
  • Employs AutoRANGER technology that automatically adjusts the trip threshold based on load.

Note: Consult factory for available radio solution.


The SEL-WSO is approved for use in the following countries: 

  • United States (including the District of Columbia, Puerto Rico, Guam, American Samoa, and the American Virgin Islands)
  • Canada

A license or other permissions may be required for use in other countries. For requests for use in other countries or for more information, please contact SEL.

   SEL-WSO Specifications*
Trip Threshold Range50 to 1,200 A
System Voltage Range (L-L)4,160 V to 34.5 kV
Maximum Fault Current25 kA
Battery3.6 V high-capacity 38 Ah lithium battery with a 20-year shelf life
Approximate Weight728 g (1.6 lbs)
Outer Diameter Clamp Range0.162" to 1.50"
Required NetworkRPMA (Trilliant Networks)

*Approved for use by the governments of the United States and Canada.


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