The SL-510 (upward-looking) and SL-610 (downward-looking) pyrgeometers are designed for accurate and stable incoming and outgoing longwave radiation measurement.
Accurate, Stable Measurements
Calibration in controlled laboratory conditions is traceable to the World Infrared Standard Group in Davos, Switzerland. Long-term non-stability, determined from multiple replicate pyrgeometers in accelerated aging tests and field conditions, is less than 2% per year.
Rugged, Self-cleaning Housing
The patented domed shaped sensor head 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.
A 0.2 W heater keeps water (liquid and frozen) off the sensor and minimises errors caused by dew, frost, rain or snow blocking the radiation path.
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 filter, blackbody thermopile detector and thermistor (to measure detector temperature) are all contained in a compact housing that provides improved thermal coupling.
|Sensitivity||0.12 mV per W m-2 (Variable from sensor to sensor, typical value listed)|
(Reciprocal of Sensitivity)
|8.5 W m-2 per mV (variable from sensor to sensor, typical value listed)|
|Output Range||-24 to 24 mV|
|Measurement Range||-200 to 200 W m-2 (net longwave irradiance)|
|Measurement Repeatability||Less than 1%|
|Long-term Drift||Less than 2% change in sensitivity per year|
|Non-linearity||Less than 1%|
|Detector Response Time||0.5s|
|Field of View||150°|
|Spectral Range||5 to 30 um (50% points)|
|Temperature Response||Less than 0.1% °C-1|
|Window Heating Offset||Less than 10 W/m-2|
|Zero Offset B||Less than 5 W/m-2|
|Tilt Error||Less than 0.5%|
|Uncertainty in Daily Total||±5%|
|Temperature Sensor||30k Ω thermistor, ±1°C tolerance at 25°C|
|Output from Thermistor||0 to 2500mV (typical, other voltages can be used)|
|Input Voltage Requirement for Thermistor||2500mV excitation (typical, other voltages can be used)|
|Warranty||4 years against defects in materials and workmanship|
Applications include longwave radiation measurement in agricultural, ecological, and hydrological weather networks and renewable energy applications.