CM121B/C Shadow Ring

The combination of a global measurement instrument and the CM121B/C Shadow Ring offers a simple solution to the problem of measuring diffuse radiation from the sky. The shadow from the ring covers the pyranometer dome completely. The ring will not need adjustment for several days. Naturally the ring will also intercept a small part of the diffuse radiation from the sky. Correction is necessary to compensate for this and a table is provided.

When it is desired to use the shadow ring with an instrument fitted with the CVF4 ventilation unit it is necessary to order the CM121C version. This has a factory fitted adapter to correct for the extra height of the CVF4.

A measuring instrument is not included, and must be ordered separately.