When you connect the sensor to the BNC connector in the IEPE mode, the LED light will indicate the following operation stages. The LED lights are the same in channel setup or in an active measurement.  
  • LED Off when no sensor is connected or sensor cable break occurs. Bias voltage >19V
  • LED Green when bias voltage within limits.
  • LED Red when sensor short detected, bias voltage <4V.
  • LED Orange when the FW of the module is updating.