The radiometer LP UVI 02 measures the global effective irradiance on a flat surface (Watt / m2 effective), according to the requirements of the WMO for the measurement of UV-index. The global irradiance is the sum of direct sun and of diffuse irradiance. In the ultraviolet spectral region, unlike what occurs in the portion of the visible light where the direct component is prevalent on the diffuse component, the light is strongly scattered in the atmosphere, and then the two components are equal; it is therefore of primary importance that the radiometer is able to accurately measure both components.
The radiometer LP UVI 02 is produced with current output or voltage output:
LP UVI 02 AC is a current loop transmitter (4÷20mA) with measuring range 0÷16 UV-index,
LP UVI 02.1 AC is a current loop transmitter (4÷20mA) with measuring range 0÷20 UV-index,
LP UVI 02 AV is a voltage loop transmitter with measuring range 0÷16 UV-index; the output, depending on the version, is: 0-1V, 0-5V 0-10V.
LP UVI 02.1 AV is a voltage loop transmitter with measuring range 0÷20 UV-index; the output, depending on the version, is: 0-1V, 0-5V 0-10V.
The versions 02.1 have a full scale that reach 20 UV-index and are suitable for the measurement of UV in equatorial areas and high mountain; as demonstrated by recent studies, in these places index value UV of 11 can be exceeded for a significant time.
The power supplied is required at 8-30 Vdc, except for the version LP UVI 02 AV10 (voltage output 0-10 V) which is of 15-30 Vdc.
The instrument is managed to operate for long periods without maintenance (except cleaning of the dome and checking the status of silica gel) provided that it is properly powered. This feature makes the device ideal for use in remote weather stations also.