Apogee SI-4HR-SS – Research-Grade SDI-12 Road Surface Infrared Radiometer Sensor

The SI-4HR-SS infrared radiometer is developed for road weather networks specifically, with a 10° vertical field of view, allowing for remote detection of a narrow and distant target roadway. The rectangular-shaped aperture maximizes the horizontal field of view allowing for a larger integrated measurement without including undesired target areas such as sky or surrounding terrain. The elongated external shield is designed to better protect from snow and ice building up on the sensor. The SI-4HR has an SDI-12 digital output and high-quality cable terminating in pre-tinned pigtail leads for easy connection to dataloggers and controllers. The sensor has a response time of 0.6 seconds. Sensor includes IP68 marine-grade stainless-steel cable connector 30 cm from head to simplify sensor removal and replacement for maintenance and recalibration.

FOR MORE PRODUCT INFORMATION, CHECK OUT THESE LINKS

• Product Manual

• Specification Sheet

• Technical Drawing

Input Voltage Requirement
5.5 to 24 V DC

Current Draw
1.5 mA (quiescent), 2.0 mA (active)

Calibration Uncertainty (-30 to 65 C)
0.3 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
Less than 0.05 C

Stability (Long-term Drift)
Less than 2 % change in slope per year when germanium filter is maintained in a clean condition

Response Time
0.6 s, time for detector signal to reach 95 % following a step change, fastest data transmission rate for SDI-12 circuitry is 1 s

Field of View
5° vertical half angle; 16° horizontal half angle

Spectral Range
8 to 14 µm; atmospheric window

Operating Environment
-50 to 80 C; 0 to 100 % relative humidity (non-condensing)

Dimensions
23 mm diameter, 60 mm length

Mass
219 g (with 5 m of lead wire)

Cable
5 m of four conductor, shielded, twisted-pair wire with TPR jacket (high water resistance, high UV stability, flexibility in cold conditions), aditional cable available

Warranty
4 years against defects in materials and workmanship

Manufactured
Made in the USA