Solar Radiation Sensor (Thermopile)

Solar radiation sensor that is applied in general observations. Pyranometer measures the solar radiation received by a plane surface from a 180 A field of view angle. This quantity, expressed in W/m2, is called a hemisphericala solar radiation. The solar radiation spectrum extends roughly from 285 to 3000 x 10-9 m. By definition a pyranometer should cover that spectral range with a spectral selectivity that is as a flata as possible.
In an irradiance measurement by definition the response to a beama radiation varies with the cosine of the angle of incidence; i.e. it should have full response when the solar radiation hits the sensor perpendicularly (normal to the surface, sun at zenith, 0 A angle of incidence), zero response when the sun is at the horizon (90 A angle of incidence, 90 A zenith angle), and 50 % of full response at 60 A angle of incidence.
A pyranometer should have a so-called a directional responsea (older documents mention a cosine responsea ) that is as close as possible to the ideal cosine characteristic. The pyranometer is easy to mount and install. This sensor offers analogue millivolt output. . It is ideal for general solar radiation measurements in (agro-) meteorological networks and PV monitoring.