The 240-152 Shadow Band is used with a pyranometer for measurement of diffuse sky radiation. The shadow band prevents direct solar radiation from reaching the pyranometer. If used in conjunction with a second pyranometer without a shadow band, direct radiation can be calculated by finding the difference between the two pyranometer measurements.
The shadow band is ruggedly constructed of black anodized aluminum, weighs approximately 24 pounds, and uses a 3" band of approximately 25" diameter to shade the pyranometer. A platform at the center supports the pyranometer in a level position. The declination setting must be adjusted regularly. Engraved markings for latitude and solar declination make the device easy to set up.