Second class pyranometer ISO9060
The pyranometer measures global solar radiation on a plane/level surface (Watt/m²). The Measured radiation is the sum of direct solar radiation and diffuse sky radiation (global radiation).
The sensor complies with ISO 9060 second class pyranometers and to WMO publication “Guide to meteorological Instruments and Methods of Observation”, 5th edition (1983).
The sensor is based on a thermopile sensor. The sensing surface of the thermopile is coated with an opaque black paint providing a flat spectral response for the full wavelength range.
The spectral range of the pyranometer is determined by the transmission through the glass dome K5 type.
The irradiance energy is absorbed by the blackened surface of thermopile providing a temperature difference between the centre of the sensor (hot junction) and the body of pyranometer (cold junction). This difference is then converted to a voltage according to the Seeback effect.
The sensor has a dome with 32 mm external diameter and 4 mm thickness to guarantee correct thermal insulation from wind and to reduce sensitivity to thermal radiation. The dome protects the thermopile from the dust which could modify spectral sensitivity. The sensor is then provided with a bubble level for the correct levelling of the sensor.
To avoid condense formation on the inner surface of the dome, moisture absorbing silica-gel is put inside the pyranometer.
The sensor is equipped with a protection shield (PCTRA066).