The SP-510 (upward-looking) and SP-610 (downward-looking) thermopile pyranometers are designed for accurate and stable global shortwave radiation measurement and reflectance.
Accurate, Stable Measurements
Calibration in controlled laboratory conditions is traceable to the World Radiometric Reference in Davos, Switzerland. The upward-looking model is cosine-corrected, with directional errors less than 20 W m2 at 80° solar zenith angle. Long-term non-stability, determined from multiple replicate pyranometers in accelerated aging tests and field conditions, is less than 2% per year.
Rugged, Self-cleaning Housing
Patented domed shaped sensor head (diffuser and body) for the upward-looking model facilitates runoff of dew and rain to keep sensor clean and minimise errors caused by dust blocking the radiation path. Sensors are housed in a rugged anodised aluminium body, and electronics are fully potted.
Multiple analogue output options are available including: 0 to 114mV, 0 to 2.5V, and 0 to 5.0V ranges. The thermopile pyranometer is also available attached to a hand-held meter with digital readout.
A thermally-insulated base is included to be mounted between the sensor and levelling plate. The AM-110 mounting bracket facilitates mounting the AL-100 levelling plate to a mast or pipe. The bubble-level in the plate makes levelling simple and accurate.
Designed to optimise performance and price. The upward-looking model combines a blackbody thermopile detector and acrylic diffuser, and is a significant improvement when compared to the spectral response of silicon-cell pyranometers, but keeps the price close to that of silicon-cell pyranometers. The downward-looking model combines a blackbody thermopile detector and flat glass window. It performs similarly to domed downward-looking thermopile pyranometers, but without the cost of the dome.
A 0.2 W heater keeps water (liquid and frozen) off the sensor and minimises errors caused by dew, frost, rain, and snow blocking the radiation path.
|Sensitivity (variable from sensor to sensor, typical values listed)||0.057 mV per W m-2||0.15 mV per W m-2|
|Calibration Factor (reciprocal of sensitivity)
(variable from sensor to sensor, typical values listed)
|17.5 W m-2 per mV||6.7 W m-2 per mV|
|Output Range||0 to 114 mV||0 to 300 mV|
|Measurement Range||0 to 2000 W m-2 (net shortwave irradiance)|
|Measurement Repeatability||Less than 1%|
|Long-Term Drift||Less than 2% per year|
|Non-Linearity||Less than 1%|
|Detector Response Time||0.5s|
|Field of View||180°||150°|
|385nm to 2105nm||295 to 2658nm|
|Directional (Cosine) Response||Less than 20 W m-2 at 80° solar zenith|
|Temperature Response||Less than 0.1% °C-1|
|Zero Offset A||Less than 5 W m-2; Less than 10 W m-2 (heated)|
|Zero Offset B||Less than 5 W m-2|
|Uncertainty in Daily Total||Less than 5%|
|Warranty||4 years against defects in materials and workmanship|
Applications include shortwave radiation measurement in agricultural, ecological, and hydrological weather networks and solar panel arrays.