LI-200 Pyranometer SensorMeasures Total Solar Radiation
Patterned after the work of Kerr, Thurtell and Tanner (2), the LI-200 features a silicon photovoltaic detector mounted in a fully cosine-corrected miniature head. Current output, which is directly proportional to solar radiation, is calibrated against an Eppley Precision Spectral Pyranometer (PSP) under natural daylight conditions in units of watts per square meter (W m-2). Under most conditions of natural daylight, the error is < 5% (2).
The spectral response of the LI-200 does not include the entire solar spectrum, so it must be used in the same lighting conditions as those under which it was calibrated. Therefore, the LI-200 should only be used to measure unobstructed daylight. It should not be used under vegetation, artificial lights, in a greenhouse, or for reflected solar radiation.
The LI-200 Pyranometer spectral response is illustrated along with the energy distribution in the solar spectrum (3). References
Calibration: Calibrated against an Eppley Precision Spectral Pyranometer (PSP) under natural daylight conditions. Typical error under these conditions is ± 5%. Sensitivity: Typically 90 µA per 1000 W m-2. Linearity: Maximum deviation of 1% up to 3000 W m-2. Stability: < ± 2% change over a 1 year period. Response Time: 10 µs. Temperature Dependence: 0.15% per °C maximum. Cosine Correction: Cosine corrected up to 80° angle of incidence. Azimuth: < ± 1% error over 360° at 45° elevation. Tilt: No error induced from orientation. Operating Temperature: - 40 to 65 °C. Relative Humidity: 0 to 100%. Detector: High stability silicon photovoltaic detector (blue enhanced). Sensor Housing: Weatherproof anodized aluminum case with acrylic diffuser and stainless steel hardware. Size: 2.38 Dia. x 2.54 cm H (0.94” x 1.0”). Weight: 28 g (1 oz). Cable Length: 3.0 m (10 ft). There are three different terminations available for the LI-200 Pyranometer: The LI-200SA Pyranometer has a cable that terminates with a BNC connector. This allows for easy and direct connection to the LI-250A Light Meter or LI-1400 DataLogger. The LI-200SZ Pyranometer terminates with bare leads (no connector). It can be connected to a data acquisition device or datalogger that measures millivolts when a 147 Ohm shunt resistor is used. As an alternative, the 2220 Millivolt Adapter can be purchased with the LI-200SA. The 2220 Millivolt Adapter uses a 147 Ohm precision resistor to convert the LI-200 output from microamps to millivolts. The LI-200SL is an LI-200SA and a standardized output millivolt adapter. The LI-200SL produces a standardized10 mV/1000 W m-2 output that eliminates the need to change calibration constants or multipliers when SL type sensors are exchanged in the field. The LI-200 Pyranometer comes with a standard 10 feet (approximately 3 m) of cable. You may also order the LI-200 with 50 feet (approximately 15 m) of cable using the LI-200SA-50, LI-200SZ-50 or LI-200SL-50 part numbers. 50-foot and 100-foot extension cables are also available. The 2003S Mounting and Leveling Fixture is recommended for each sensor unless other provisions for mounting are made. Other accessories are described on the Accessories Page. LI-200SA Pyranometer (with BNC connector) LI-200SZ Pyranometer (with bare leads) LI-200SL Pyranometer (LI-200SA and standardized millivolt adapter) LI-200SA-50 Pyranometer (with BNC connector) LI-200SZ-50 Pyranometer (with bare leads) LI-200SL-50 Pyranometer (LI-200SA-50 and standardized millivolt adapter) 2220 Millivolt Adapter (used with the LI-200SA) 2003S Mounting and Leveling Fixture 2222SB-50 Extension Cable (50 ft) for the LI-200SA and LI-200SL 2222SB-100 Extension Cable (100 ft) for the LI-200SA and LI-200SL
Additional literature related to the LI-200 is also available:
If you have any questions about the LI-200 please feel free to contact us and discuss with our Applications Analysts and Scientists (or your local LI-COR Distributor) how the LI-200 can help you with your research. Selected Links
Please submit your published papers or links to your websites to be featured here by contacting the Product Manager, Mr. Brent Claassen. Journal ReferencesUse the academic search engines below to find references to the LI-200 in many peer reviewed scientific publications. For best results, start with the search terms provided below or use the forms to customize a search. Results open in a new window. References from HighWire Press - Internet Imprint of the Stanford University Libraries
References from Google Scholar™Common Internet searches can be performed with Google, and many articles can be found with Google Scholar: The LI-200 includes a printed copy of the Instruction Manual. You can download future updates of the LI-200 manual on this page.
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The LI-200 Pyranometer is designed for field measurement
of global solar radiation in agricultural, meteorological,
and solar energy studies. In clear, unobstructed daylight
conditions, the LI-COR pyranometer compares favorably
with first class thermopile-type pyranometers (1, 4),
but is priced at a fraction of the cost.
