Calibration Traceability

Apogee SP-500 and SP-600 sensors are calibrated through side-by-side comparison to the mean of four Apogee transfer standard sensors under high intensity discharge metal halide lamps. The transfer standard sensors are calibrated through side-by-side comparison to the mean of at least two ISO-classified reference pyranometers under sunlight in Logan, UT. Each of two

ISO-classified reference sensors are recalibrated on an alternating year schedule at the National Renewable Energy Laboratory (NREL) in Golden, Colorado. NREL reference standards are calibrated to the World Radiometric Reference (WRR) in Davos, Switzerland.

Features:

Output Options

• 0 to 114 mV

• Downward sensor available for measuring shortwave reflectance, or combine with an upward head to measure albedo

Unique Design

The thermopile, blackbody detector results in significant spectral response improvements over silicon-cell pyranometers. A small design keeps the price low and optimizes power requirement for the 0.2 W heater that minimizes errors from dew, frost, and snow.

Accurate, Stable Measurements

Directional errors are less than 30 W m⁻² 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.

Typical Measurement Applications

• Solar panel arrays

• Agricultural, ecological, and hydrological weather networks

Product Specifications:

Manufacturer: Apogee, USA