CMP 3 Pyranometer

The affordable CMP3 pyranometer from Kipp & Zonen is a device for measuring global radiation (solar radiation) incident on the thermocouple sensor of a sensor from a whole hemisphere located above the spherical cover of the sensor. The output signal of the sensor is in microvolts and its magnitude corresponds to the incident energy of shortwave solar radiation in watts per m².

The CMP3 pyranometer is designed for continuous outdoor and indoor use. The spectral sensitivity of the pyranometer is from 310 to 2800 nm. The maximum measuring range is up to 2000 W / m², the time constant of the pyranometer is 18 sec (95% of the measured value) and the typical sensitivity is 10 uV / W / m². In the temperature range from -10 ºC to +40 ºC, the measurement accuracy is better than 5%.

The operating temperature of the CMP3 pyranometer can range from -40 ºC to +80 ºC. Long-term output stability is better than 1% per year.

The CMP3 pyranometer comes with a snap-on white plastic screen that prevents unwanted reflections of sunlight from the second averted hemisphere and also forms a cover for the connector with a ten-meter shielded cable, which is also standard on the CMP3 pyranometer.

Each CMP3 pyranometer is accompanied by a calibration certificate from the manufacturer (it contains a calibration constant for setting the sensitivity of the connected amplifier-datalogger). The M4016 telemetry station contains a multiplicative coefficient A1 for each recording channel, into which the inverse value of the calibration constant is entered when installing the pyranometer. The coefficient A1 can be easily changed at any time (from the keyboard of the unit and remotely via a web browser and the MOST program) after a possible recalibration of the CMP3 pyranometer.

The two CMP3 pyranometers can also be screwed back together to obtain an albedometer (a sensor incident from the earth's surface reflected by solar radiation).

Basic technical parameters

Parameter	Value
Spectral range	310 to 2800 nm
Time constant	18 sec (95%)
Zero error	± 15 W/m²
Error due to angle of incidence (80° při 1000 W/m²)	± 20 W/m²
Temperature dependence of sensitivity (-10 ºC to +40 ºC)	± 5 %
Operating temperature	-40 °C to +80 °C
Maximum measured value	2000 W/m²
Scanned area	180 °