Campbell Scientific Kipp and Zonen CMP-Series Pyranometers - Manual (Page 24)

CMP/CMA series manual
Page 23
6. CMP/CMA models
The CMP series offers 5 different models in the range from CMP 3 up to CMP 22. The mechanical
construction of the CMP 3 differs from the others in that it has a single dome, smaller housing
dimensions and no drying cartridge (the housing is completely sealed). Features and specification of
the double dome pyranometers in the range from CMP 6 to CMP 22 are specified in this chapter. The
CMP/CMA series is designed for measuring the irradiance (radiant-flux, W/m
2
) on a plane surface,
which results from the direct solar irradiance and from the diffuse radiation incident from the
hemisphere above.
A CMP/CMA radiometer includes an integrated bubble level, refillable drying cartridge, white snap-on
sun shield, and a shielded signal output cable with connector. In addition, the CMA series
albedometers also have an integrated conical lower glare shield to prevent illumination of the lower
glass dome at sunrise and sunset. The albedometers are equipped with a mounting rod for attachment
to a mast. All albedometers are supplied with a calibration certificate indicating both the upper and
lower sensor sensitivities.
The CMP series (except CMP 3) can be used in conjunction with the Kipp & Zonen CV 2 ventilation
unit for enhanced measurement performance and overall reduced instrument maintenance.
For measuring the diffuse component of solar radiation only, the direct solar component can be
shielded statically from the CMP pyranometers by the Kipp & Zonen shadow ring CM 121, and fully
automatically by the 2 AP sun tracker with shading system.
6.1. CMP 6 / CMA 6
Fully compliant with all ISO-9060 specification criteria for an ISO First Class pyranometer, the
CMP/CMA 6 features a sixty-four junction (connected in series) thermocouple sensing element. The
sensing element is coated with a highly stable carbon based inorganic coating, which delivers excellent
spectral absorption and long-term stability characteristics. The detector is housed under two concentric
glass domes which are 2 mm thick.
The albedo version is constructed around two CMP 6 pyranometer sensors and also complies with the
ISO classification. Both sensors are contained in a single housing and have individual sensitivities.
6.2. CMP 11 / CMA 11
Fully compliant with all ISO-9060 specification criteria for an ISO Secondary Standard pyranometer,
the CMP 11 features a 32 junction (connected in series) thermocouple sensing element which has
faster response than the CMP 6 / CMA 6. Passive temperature compensation is included for improved
temperature dependence of sensitivity and non-linearity is reduced. The sensing element is housed
under two higher quality concentric glass domes which are 2 mm thick and provide improved
directional error. The radiometric leveling is more accurate than in CMP 6 / CMA 6.
CMA 11 is constructed around two CMP 11 pyranometer sensors. Both sensors are contained in a
single housing and have individual sensitivities.