Configuring Power Failure Sensor

The Power Failure sensor detects real-time power failure.

  • Monitors the on/off state of a power source, such as main power, a UPS, surge protector or standard wall outlet. 
  • Plug the Power Failure Sensor into the source you wish to monitor.
  • Sensor outputs Open dry contact output when no power is detected.
  • Sensor is connected to Varius Message Router with 8 dry contact inputs.
  • Varius Message Router sends out alerts when Open dry contact output is detected.


1. Connecting sensor to Varius Message Router

  1. The Power Failure Sensor comes with one end of the  speaker cable already attached to its switch port.
  2. Separate and strip the leads on the free end of the speaker cable.
  3. Connect the two free ends of the speaker cable to two consecutive dry contacts input of Varius Message Router with 8 dry contact inputs.
  4. In the example, the dry contact inputs connected are the two right most inputs which correspond to the Switch 1 out of 8 switch sensors.
2. Connecting sensor to power source
  1. Connect the included power adapter to the power port on the Power Failure Sensor.
  2. Insert the adapter plug into the power source you wish to monitor for instance, a wall socket.
  3. The sensor outputs:
    – Power On: Closed dry contact output
    – Power Off: Open dry contact output
3. Connecting Varius Message Router to UPS
  1. Connect Varius Message Router with 8 dry contacts input to a UPS system so that it can send out alerts in times of power failure.
  2. Varius Message Router has an optional UPS output connector to connect to a UPS.
  3. The recommended alert mechanism is SMS as compared to email alert because network equipment can be not functional in times of power failure.


  1. Login to the web interface of Varius Message Router (VMR).
  2. From the menu, access Sensors > Sensors Configuration.
  3. If switch sensors do not exist in the sensors list, select Switch Sensors (x8) and click Add Sensor.
  4. From the list of switch sensors, edit the switch sensor that is connected to the Power Failure Sensor.
  5. Click on the Edit button beside the sensor type to edit the sensor.
  6. In our example, Switch 1 is selected. 
    Set Trip conditions, alert conditions and alert mechanisms.
  7. You can configure the alert profiles that appear in the Alert Mechanisms section. 
    The alert profile types are email and SNMP traps.
    You can send out SMS alerts by creating an email alert profile that specifies VMR as the SMTP server to utilize the email to SMS functionality of VMR. 
    For more information, please refer to Configuring Sensor Alert Profiles.
  8. Once configuration is completed, access the Sensors Control Panel to start and stop the Sensors service for the change to take effect.

Sensors Control Panel

From the menu, access Sensors > Sensors Control Panel to access the page.

This page shows the latest  status of the active sensors.

For any changes to sensors configuration, please click stop and start the Sensors service.

Viewing Sensor Logs

From the Sensors Control Panel, click on the View Logs link beside the Power Failure Sensor status.

Logs can be exported in CSV format.