CGR4 pyrgeometer – Accurate longwave radiation
CGR4 pyrgeometer is an instrument for the highest quality scientific measurements of downward longwave radiation. The specially designed meniscus dome provides a 180º field of view with negligible directional response error. A hard-carbon coating on the outside of the dome smoothes the spectral response and provides extra protection to the silicon surface.
The excellent thermal stability of the dome construction and coupling to the instrument body eliminates the need for dome temperature measurements or dome shading.
The CGR4 can be fitted with the CVF4 ventilation unit to further improve its performance.
A waterproof socket is fitted for the signature yellow signal cable, which is available in a range of lengths pre-wired to the waterproof plug.
The integral bubble level is raised to the top of the housing and can be viewed without removing the redesigned snap-on sun shield, which also covers the connector. The connector with gold-plated contacts allows for easy exchange and re-calibration. The screw-in drying cartridge is easy to remove and the replacement desiccant is supplied in convenient refill packets.
|Spectral range (50% points)||4.5 to 42 µm = 4500 to 42000 nm|
|Sensitivity||5 to 15 µV/W/m²|
|Response time||18 s|
|Window heating offset||< 4 W/m²|
|Zero offset B||< 2 W/m²|
|Temperature dependence of sensitivity (-20 ºC to +50 ºC)||< 1 %|
|Operational temperature range||-40 to +80 °C|
|Net irradiance range||-250 to + 250 W/m²|
|Field of view||180 °|
|Non-linearity||< 1 %|