CNR4 net radiometer

Light weight net radiometer with all 4 sensors integrated into one instrument body. The only integrated net radiometer available with a ventilation and heating unit.


The CNR4 net radiometer consists of a pyranometer pair, one facing upward, the other facing downward, and a pyrgeometer pair in a similar configuration. The pyranometer pair measures the short-wave radiation. And the pyrgeometer pair measures long-wave radiation. The upper long-wave detector of CNR4 has a meniscus dome. This ensures that water droplets role off easily and improves the field of view to nearly 180°, compared with a 150° for a flat window. All 4 sensors are integrated directly into the instrument body, instead of separate modules mounted onto the housing. But are each calibrated individually for optimal accuracy.


Spectral range (50% points) 0.3 to 2.8 µm = 300 to 2800 (short wave) nm
Spectral range (50% points) 4.5 to 42 µm = 4500 to 42000 (long wave) nm
Sensitivity 5 to 20 µV/W/m²
Temperature dependence of sensitivity (-10 ºC to +40 ºC) < 4 %
Response time < 18 s
Non-linearity < 1 %
Operating temperature -40 to 80 °C
Ventilation power (of the optional CNF4 ventilation unit) 10 W