Campbell Scientific 109-L Temperature Probe - Manual (Page 20)

Model 109 Temperature Probe
Symptom: Incorrect temperature is reported.
Verify the Mult and Offset arguments in Therm109() are correct for the
desired units (Section 7.2, Datalogger Programming). Check the cable for
signs of damage and possible moisture intrusion.
Symptom: Unstable temperature is reported.
Probably a result of electromagnetic interference. Try using the _50Hz or
_60Hz Integ or Fnotch options, and/or increasing the settling time as
described in Section 8.3, Electrically Noisy Environments, and Section 8.4,
Long Cable Lengths. Ensure the clear wire is connected to datalogger
ground, and the datalogger is properly grounded.
9.2 Maintenance
The 109 probe requires minimal maintenance. For air temperature
measurements, check the radiation shield monthly to make sure it is clean and
free from debris. Periodically check cabling for signs of damage and possible
moisture intrusion.
9.3 Calibration
Calibration of the 109 probe is not necessary unless the application requires
removal of the thermistor interchangeability offset described in Section 6,
Specifications.
10. Attributions and References
Santoprene ® is a registered trademark of Exxon Mobile Corporation.
Measurement Specialties™ is a trademarked global designer and manufacturer
of sensors and sensor-based systems.
EPA installation standard: Quality Assurance Handbook for Air Pollution
Measurement Systems – Volume IV: Meteorological Measurements Version 2.0
WMO standard: WMO No. 8, Seventh edition, 6 Aug 2008 Guide to
Meteorological Instruments and Methods of Observation
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