The LI-200R Pyranometer is meant to be used outdoors under unobstructed natural daylight conditions. It measures global solar radiation—the combination of direct and diffuse solar radiation—in the 400 to 1100 nm range. Measurement units are in watts per square meter (W m-2).
Ideal for agricultural, meteorological, solar energy, and environmental research, the LI-200R is available with a variety of cable lengths and compatibility with most data loggers.
Weather resistant and durable in long-term outdoor deployments
Measures global solar radiation under unobstructed natural daylight conditions
Uniform sensitivity up to 82° incident angle
Detachable sensor simplifies installation and removal, making it ideal for platforms with complex cabling
How does it work?
The LI-200R measures global solar radiation with an unfiltered silicon photodiode. Its measurements correspond closely to first-class thermopiles when used outdoors under unobstructed natural daylight conditions.
The crown of the sensor rapidly sheds water, and also physically blocks light from outside the hemisphere of sensitivity, providing a precise cosine response.
Absolute Calibration: Calibrated against an Eppley Precision Spectral Pyranometer (PSP) under natural daylight conditions. Calibration uncertainty under these conditions is estimated as ± 3% typical, within ± 60° angle of incidence.*
Sensitivity: Typically 75 μA per 1,000 W m-2
Linearity: Maximum deviation of 1% up to 3,000 W m-2
Response Time: Less than 1μs (2 m cable terminated into a 147 Ohm load)
Temperature Dependence: ± 0.15% per °C maximum
Cosine Correction: Cosine corrected up to 82° angle of incidence
Azimuth: < ± 1% error over 360° at 45° elevation
Tilt: No error induced from orientation
Operating Temperature Range: −40 °C to 65 °C
Relative Humidity Range: 0% to 95% RH, Non-Condensing
Detector: High stability silicon photovoltaic detector (blue enhanced)
Sensor Housing: Weatherproof anodized aluminum body with acrylic diffuser and stainless steel hardware; O-ring seal on the sensor base
Size: 2.36 cm diameter × 3.63 cm (0.93” × 1.43”)
Weight: 24 g head; 60 g base and cable (2 m) with screws
Cable Length: 2 m, 5 m, 15 m, 50 m (6.5’, 16.4’, 49.2’, 164’)