The CMP21 Pyranometer is a secondary standard pyranometer that is similar to the CMP11 but has individually optimised temperature compensation. The CMP21 uses a 32-junction thermopile detector and provides an expected output of 0-20mV based on a sensitivity of 7 to 14µV/Wm². The CMP21 has two, 2mm thick, high quality concentric domes which reduces directional error and improves thermal isolation. The CMP21 has an internal 10K thermistor, or PT100, sensor to monitor the housing temperature, ...