Missing logged values usually mean the logger is not consistently receiving, storing, or mapping the measurement data. The cause depends on whether data was never logged or whether logging suddenly stopped.
Possible causes:
  • The channel is not configured correctly in the logger or the sensor was removed from the logging configuration.
  • Logging interval, memory handling, or trigger settings are incorrect.
  • Communication to the sensor is intermittent or has been interrupted.
  • Power supply interruptions or failures affect the logger or sensor.
  • The selected variable is displayed live but not assigned correctly for recording.
  • Physical cable connection has degraded or been accidentally disconnected.
Diagnostic approach for data that suddenly stopped:
  • Check recent system changes – ask whether anyone has modified, serviced, or reconfigured the system recently; check if cables were unplugged or equipment was moved.
  • Verify power supply to the sensor – confirm that supply voltage is still present at the sensor terminals; power loss is a common cause of sudden data loss.
  • Test the physical cable – inspect the communication cable for damage, looseness, or degradation; test with a known-good cable to rule out cable failure.
  • Review logger configuration changes – check whether the sensor was accidentally removed from the logging assignment or whether channel mapping was altered.
  • Review timestamps – identify whether gaps in logged data coincide with power interruptions, communication dropouts, or known system maintenance events.
Diagnostic approach for configuration-related issues:
  • Verify channel mapping, tag assignment, and recording parameters – ensure the sensor is correctly assigned to a data logger channel and that recording is enabled.
  • Check communication status – review the logger diagnostic menu for communication errors or sensor dropouts.
  • Confirm storage and memory – verify that the storage medium and memory capacity are functioning correctly and have not reached capacity limits.
  • Test with a shorter interval and stable connection – use a shorter logging interval with direct connection to the logger to confirm whether the issue is configuration-related or hardware-related.