Solar / UV Interface

Initially, the Solar Radiation / UV interface was designed to allow WeatherDuino weather stations to measure solar radiation and UV Index data at very low cost, using a small photovoltaic panel as a sensor. The concept is based on an article by Charles G. Wright, entitled Measuring Solar Radiation.
Despite its simplicity, a solar radiation sensor based on a photovoltaic panel works quite well, and its readings are comparable to those from expensive pyranometers.
The Solar Radiation / UV interface can also be used with commercially available pyranometers, provided their output voltage does not exceed 1.1V. This has been tested with the Apogee SP-110 Pyranometer.
For UV index, we have chosen to use the UVM-30A UV sensor.

Usually the Solar Radiation / UV interface is supplied as a kit that includes the fully assembled interface, plus a tested miniature photovoltaic panel. The op amp gain is pre-calibrated for the supplied photovoltaic panel, allowing solar radiation readings up to 1500 W/m² .
Optionally it can be supplied without the photovoltaic panel.
The UVM-30A UV sensor for UV Index isn't included. This sensor is easy to find, costs around 5€, and can be bought from several sellers on eBay or other sources.

The easiest way to measure solar radiation data with your weather station is by using the Solar / UV interface with a ready made pyranometer, such as the Apogee SP-110.
For those who like a challenge, the use of the photovoltaic panel is a cheap alternative to a commercial pyranometer.
In the WeatherDuino support forum there is an extensive article on this topic which we strongly recommend you read: Measuring Solar Radiation based on Photovoltaic Cells.

Example of a commercial pyranometer that uses a miniature photovoltaic panel.

The Apogee SP-110 Self-Powered Pyranometer.

… under construction …