LPPYRA13 pyranometer measures the irradiance on a flat surface (W/m2). Thanks to the shadow-ring, LPPYRA13 measures the diffuse solar radiation eliminating the contribution of direct irradiance.
PPYRA13 is equipped with a Spectrally Flat Class A (Secondary Standard) pyranometer (LPPYRA10) in accordance with ISO 9060:2018 and with the criteria of the WMO “Guide to Meteorological Instruments and Methods of Observation”.
LPPYRA13 pyranometer is based on a thermopile sensor. The thermopile sensitive surface is coated with a black matt paint, which allows the pyranometer not to be selective at different wavelengths. In order to grant the thermopile a proper thermal insulation from the wind and reduce the sensitivity to thermal irradiance, LPPYRA13 is equipped with two concentric domes having 50 mm and 32 mm outer diameter. The domes protect the thermopile from the dust, which might change spectral sensitivity if it lies on the black surface. The pyranometer spectral range is determined by the transmission of the two glass domes. Thanks to the use of a new material for the manufacturing of the domes, the spectral range has been further extended to short wavelengths starting from 283 nm.