The 109 is a rugged, accurate probe that measures air, soil, and water temperature for a variety of applications. It consists of a thermistor encapsulated in an epoxy-filled aluminum housing. The housing protects the thermistor, allowing the 109 to be buried or submerged. The 109 measures from -50° to +70°C.
Read MoreThe 109 consists of a thermistor encapsulated in an epoxy-filled aluminum housing. The housing protects the thermistor allowing it to be buried in soil or submerged in water.
This probe outputs a 0 to 2.2 V signal when using 2500 mV excitation.
Output | Analog |
Operating Temperature Range | -50° to +70°C |
Sensor Description | Measurement Specialties™ 10K3A1iA Thermistor |
Tolerance | ±0.2°C (over 0° to 70°C range) |
Temperature Measurement Range | -50° to +70°C |
Steinhart-Hart Equation Error | ≤ 0.03°C (-50° to +70°C) |
Interchangeability Error | ±0.1°C (over 0° to 70°C range increasing to ±0.5°C at -50°C) |
Time Constant in Air | 30 to 60 s (in a wind speed of 5 m s-1) |
Maximum Submergence | 15 m (50 ft) |
Maximum Cable Length | 305 m (1000 ft) |
Probe Length | 10.4 cm (4.1 in.) |
Probe Diameter | 0.76 cm (0.3 in.) |
Weight | 136 g (5 oz) with 3.05-m (10-ft) cable |
Please note: The following shows notable compatibility information. It is not a comprehensive list of all compatible products.
Product | Compatible | Note |
---|---|---|
CR1000 (retired) | ||
CR300 | ||
CR3000 (retired) | ||
CR310 | ||
CR350 | ||
CR6 | ||
CR800 (retired) | ||
CR850 (retired) |
The instruction set for our CR800-series, CR1000, and CR3000 dataloggers contains the Therm109 instruction for measuring the 109 probe. Programming is more complicated for other dataloggers because they must use generic measurement instructions.
When exposed to sunlight, the 109 must be housed in a radiation shield. It is typically housed in a 41303-5A 6-plate naturally aspirated shield. It may also be housed in a 41003-5 10-plate shield if a 41322 Adapter Plate is used. The radiation shield mounts to a mast, tower leg, or crossarm.
The 109 is suitable for shallow burial only. Placement of the cable inside a rugged conduit may be advisable for long cable runs—especially in locations subject to digging, mowing, traffic, use of power tools, or lightning strikes.
The 109 can be submerged to 50 ft. Please note that the probe is not weighted. Therefore, the installer should either add a weighting system or secure the probe to a fixed, submerged object, such as a piling.