PERFORMANCE EVALUATION FOR PYRANOMETERS
Lu Wenhua Mo Yueqin (National Center for Meteorological Metrology)
The performance of two models pyranometer (model DFY4 and model TBQ-2) made in China has been tested. We have mainly studied the long-term stability of sensitivity, nonlinearity, temperature dependence, directional response (cosine and azimuth), tilt effect,response time and et al. Sensitivity and response time are tested in outdoor exposure and others are tested on the laboratory test facility for solar radiation instruments. In our measurements we used a personal computer in conjunction with data logger and output of instruments can be measured and processed automatically. Model PSP pyranometer made in EPPLEY laboratory of USA is used as a reference instrument and its dissemination of the value of the quantity can be trace back to WRR. Main error for pyranometers is concluded according to a great of test data and analysis. It is very useful for observation and study of solar radiation.