SR11 is a solar radiation sensor that can be applied in scientific grade solar radiation observations. It complies with the "first class" specifications within the latest ISO and WMO standards. The scientific name of this instrument is pyranometer. Model SR11-TR has a special housing, which makes it possible to place a transmitter, or amplifier. For additional information on the application and use of regular SR11 pyranometer, SR11 brochure and manual can be consulted.

SR11 serves to measure the solar radiation flux that is incident on a plane surface in W/m² from a 180 degrees field of view (also called "global" solar radiation). Working completely passive, using a thermopile sensor, SR11 generates a small output voltage proportional to this flux. Employing two glass domes, certain measurement errors are reduced; in particular thermal offsets, so that a high measurement accuracy can be attained.