Apogee infrared radiometers are the most accurate non-contact temperature sensors available anywhere. The SI-131 has a 14 degree half angle field of view. The sensor has tinned leads for connecting to a datalogger. Applications include measuring the temperatures of road surfaces, plant canopies, and soil, snow and water surfaces. Measurement of surface temperature is a crucial component of energy transfer. Accurate measurement of the leaf-to-air temperature gradient is essential to the determination of transpiration rate and stomatal conductance in both single leaves and plant canopies.
If you are using any SI-100 series sensor with Campbell Scientific Dataloggers, please view the three notices from Campbell Scientific and Apogee to the right.
Model SI-131 FOV = 14.0°
|Approximate Sensitivity:||20 µV per °C|
|Output from Thermistor:||0 to 2500 mV (typical, depends on input voltage)|
|Input Voltage Requirement:||2500 mV excitation (typical, other voltages can be used)|
|Calibration Uncertainty (-20 to 65°C):||0.2°C, when target and detector temperature are within 20°C|
|Calibration Uncertainty (-40 to 80°C):||0.5°C, when target and detector temperature are different by more than 20°C|
|Measurement Repeatability:||< 0.05°C|
|Stability (Long-term Drift):||less than 2% change in slope per year when germanium filter is maintained in a clean condition|
|Field of View:||14° half angle|
|Spectral Range:||8 to 14 µm; atmospheric window|
|Operating Environment:||-55 to 80°C, 0 to 100% relative humidity (non-condensing)|
|Dimensions:||2.3 cm diameter and 6.0 cm length|
|Mass:||190g (with 5m of lead wire)|
|Cable:||5m of four conductor, shielded, twisted-pair wire. Additional cable available in multiples of 5m. Santoprene rubber jacket (high water resistance, high UV stability, flexibility in cold conditions). Pigtail lead wires.|
The SI-100 series sensors measure the temperatures of road surfaces, plant canopies, and soil, snow and water surfaces.
• Measures surface temperature rapidly
• Calibrated target temperature range from -30 to 65°C
• Uncertainty of 0.2°C (95% confidence)
• 8-14 µm germanium atmospheric window
• Radiation shield included
• Multiple field of view (FOV) options
• Rugged and lightweight
Field of View (FOV) is reported as the half-angle of the apex of the cone formed by the target (cone base) and the detector (cone apex). The target is a circle from which 98% of the radiation being viewed by the detector is being emitted.