Pyranometers are radiometers designed for measuring the irradiance on plane surface, resulting from radiant fluxes in the wavelength range from 0.3 to 3 micrometers. The most common application for pyranometers is the measurement of solar radiation and radiation from lamps. The instruments have been used in meteorological research, solar energy research, material testing, climate control in greenhouses, building physics science and many other applications.

Main characteristics of CMP pyranometers are the robustness and all weather performance. They are easy to use, require no power and are supplied with calibration certificate that is traceable to WRR (World Radiometric Reference). A record breaking 95% response time, a record breaking accuracy and a test certificate also covering the directional response, these are all important specifications to get the highest accuracy measurements.

Technical data

ISO classification: Applications include:
CMP 21 Secondary Standard Reference measurements in extreme climates, Polar or Arid. Long cable length requirements.
CMP 11 Secondary Standard High accuracy meteorological research, solar collector, testing.
CMP 6 First Class Routine measurements, agricultural stations, indoor material testing under lamps.
CMP 3 Second Class For reliable and economical routine measurements.

CM121 Shadow Ring

The CM 121B Shadow Ring is designed to be connected to a Kipp & Zonen pyranometer to shield the pyranometer sensor from direct radiation. The combination of a pyranometer and the CM 121B offers a simple solution to the problem of measuring diffuse radiation from the sky. Naturally, the ring will also intercept some of the diffuse radiation from the sky. Correction is necessary to compensate for this.


  • Suitable for all latitudes and all tilted surfaces
  • Correction factors are given in the manual
  • The shadow from the ring covers the pyranometer dome completely
  • The ring will not need adjustment for several