Campbell Scientific LI200X LI200X-L LI-COR Silicon Pyranometer - Page 5

LI200X Pyranometer 1. General Description The LI200X measures incoming solar radiation with a silicon photovoltaic detector mounted in cosine-corrected head. The detector outputs current; a shunt resistor in the sensor cable converts the signal from current to voltage, allowing the LI200X to be measured directly by Campbell Scientific dataloggers. The LI200X is calibrated against an Eppley Precision Spectral Pyranometer to accurately measure sun plus sky radiation. Do not use the LI200X under vegetation or artificial lights, because it is calibrated for the daylight spectrum (400 to 1100 nm). During the night the LI200X may read slightly negative incoming solar radiation. This negative signal is caused by RF noise. Negative values may be set to zero in the datalogger program. For more theoretical information on the silicon photovoltaic detector see Kerr, J. P., G. W. Thurtell, and C. B. Tanner: An integrating pyranometer for climatological observer stations and mesoscale networks. J. Appl. Meteor., 6, 688-694. 1.1 Specifications Stability: Response Time: Cosine Correction: Operating Temperature: Temperature Dependence: Relative Humidity: Detector: Sensor Housing: Size: Weight: Accuracy: Sensitivity: Linearity: Shunt Resistor: Light Spectrum Waveband: < ±2% change over a 1 year period 10 µs Cosine corrected up to 80° -40 to +65 °C 0.15% per °C 0 to 100% High stability silicon photovoltaic detector (blue enhanced) Weatherproof anodized aluminum case with acrylic diffuser and stainless steel hardware 0.94" dia x 1.00" H (2.38 cm dia x 2.54 cm H) 1 oz. (28 g) Absolute error in natural daylight is ±5% maximum; ±3% typical 0.2 kW m-2 mV-1 Maximum deviation of 1% up to 3000 W m-2 Adjustable, 40.2 to 90.2 Ω, factory set to give the above sensitivity 400 to 1100 nm 1