Pyranometers are used to measure global horizontal solar irradiance (GHI); which is the total effect from diffuse horizontal solar irradiance (DHI) from the sky and direct normal solar irradiance (DNI) from the sun. If shaded from the sun a pyranometer measures the DHI only.
A pyranometer tilted in the plane of array (POA) of solar panels provides critical input data for the calculation of performance ratios and efficiencies in photovoltaic energy installations.
Kipp & Zonen pyranometers have a 5-year warranty and a MTBF (Mean Time Between Failures) of more than 10 years.
All models comply with the requirements of ISO9060:1990 and are fully traceable to the World Radiometric Reference (WRR) in Davos, Switzerland, where Kipp & Zonen instruments form part of the World Standard Group.
The CMP Series
CMP series pyranometers are well known around the world for their high quality, durability and accuracy. The instruments do not require any power and each has an individual calibration factor/sensitivity.
CMP3 and CMP10 have internal desiccant that lasts for at least 10 years; the other CMP models have self-indicating desiccant in an easily accessed drying cartridge.
This ISO Second Class pyranometer is smaller and lighter than the other CMP series models. The small size and low cost make this the ideal choice for entry-level weather stations, horticulture and routine monitoring in solar energy installations.
CMP6 has a similar detector to CMP3, but improved performance due to increased thermal mass and double glass domes makes it First Class. It is recommended for cost-effective, good quality, measurements in meteorological and hydrological networks and for agriculture.
CMP10 uses a temperature compensated detector, with a different technology to the CMP3 and CMP6 that very significantly reduces measurement uncertainty. It has better performance all round and is Secondary Standard; ideal for solar energy applications, research and development and use in sun tracker based solar monitoring stations.
CMP11 is the most widely used secondary standard pyranometer in the solar energy industry for site prospecting and plant performance monitoring. It has the same performance as CMP10 but has an external drying cartridge.
CMP21 is a CMP11 with individually measured temperature and directional response (data provided) and a sensor to monitor the internal temperature. It is the choice for scientific use and in top level solar radiation monitoring networks such as the Baseline Surface Radiation Network (BSRN).
CMP22 has all the features of CMP21 but uses very high quality quartz domes for a wider spectral range, improved directional response, and reduced thermal offsets. The CMP 22 pyranometer was developed for scientific research demanding the highest level of measurement precision and consistency.
The SMP Series
The SMP range of pyranometers is based upon the proven technology of the CMP series; but has a micro-processor, memory, firmware and digital signal processing to improve performance. SMP is Smarter and faster and operates from 5 to 30 VDC.
Modbus® RS-485 communication interfaces directly to industrial networks and controllers. Up to 247 SMP pyranometers can be connected to a single network. Data is refreshed every second and the user can access irradiance, type and serial number, instrument settings, calibration history, status information, and more.
SMP pyranometers also have a fixed range analogue output; 0 to 1 V (-V models) or 4 to 20 mA (-A models); no more need to adjust data loggers after re-calibration.
SMP11 has self-indicating desiccant in an easily accessed drying cartridge; all the other SMP3 models have internal desiccant that lasts for at least 10 years.
SMP3 is the Smart version of CMP3, ideal for routine monitoring in solar energy installations. It is also Second Class, but faster response, standardised outputs and digital temperature compensation make the SMP3 superior to the CMP3.
SMP6 has similar applications to CMP6 but much better performance due to the digital temperature correction in all SMP’s, over a large range from -40 °C to +80 °C, which significantly reduces the measurement uncertainty.
SMP10, 11, 21 and 22
These Secondary Standard pyranometers are the Smart digital equivalents of the CMP series pyranometers. They have faster response and more flexible connectivity.
For extreme climates, the digital polynomial temperature correction provides better performance than the passive correction in the CMP versions.
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