Pyranometer
A pyranometer measures the global horizontal solar irradiance (GHI); which is composed of diffuse horizontal solar irradiance (DHI) from the sky and direct normal solar irradiance (DNI) from the sun. If shaded from the direct sun a pyranometer measures diffuse horizontal solar irradiance (DHI). Direct normal irradiance DNI is measured by a pyrheliometer continuously pointed at the centre of the sun by an automatic sun tracker.
ISO pyranometeres category move from second class to first class and secondary standard, depending by a well identified number (8) of instrumental characteristics.
The typical wavelenght range cover the relevant part of solar spectrum that reach Earth surface: 280 nm till 3000 nm. Limitations on that are mainly due to the quartz dome.
Technical specifications reported here are those of a top class secondary standard. The 3D model is based on the Kipp & Zonen CMP22 pyranometer.
Specifications
| Spectral range (50% points) | 285 to 2800 nm |
| Sensitivity | 7 to 14 µV/W/m² |
| Response time | < 5 s |
| Zero offset A | < 7 W/m² |
| Zero offset B | < 2 W/m² |
| Directional response (up to 80° with 1000 W/m² beam) | < 10 W/m² |
| Temperature dependence of sensitivity (-10 ºC to +40 ºC) | < 1 % |
| Operational temperature range | -40 °C to +80 °C |
| Maximum solar irradiance | 4000 W/m² |
| Field of view | 180 ° |
Italy
Germany
IB Oden
Sweden
RV Kronprins Haakon
Norway
CGS Amudsen
Canada
MSV Fennica
Finnish
RV Sikuliaq
United States
RRS Sir David Attenborough