Why is an In-Situ RDO Sensor Not Detecting?


The In-Situ RDO-Pro/Blue X-Series Integration Guide outlines the required process for integrating In-Situ RDO Sensors with NexSens X-Series data loggers. If an In-Situ RDO Sensor fails to detect after following the guide, below is a list of common reasons.

Issues During Detection

  • Issue #1: The In-Situ settings were not saved properly within the software.
    • Explanation: The parity bits on the In-Situ RDO Sensors must be changed from Even to None for proper communication.
      • Solution: Follow the integration guide to change and save the internal settings.
  • Issue #2: Two or more sensors connected to the data logger have the same Modbus address.
    • Explanation: NexSens X-Series data loggers can only read measurements from a Modbus RS-485 sensor if it has a unique address. If another connected sensor using the Modbus communication protocol has the same address, both sensors will respond simultaneously to commands. Thus, communication will be interrupted as the logger expects a specific response.
      • Solution: Review and adjust the Modbus addresses for each sensor in their respective software.