Specifications
SRA01
Measurand | hemispherical solar radiation and reflected solar radiation |
Measurement range | 0 to 2000 W/m² |
Optional measurand | albedo or solar reflectance, net solar radiation |
Sensitivity (nominal) | 15 x 10⁻⁶ V/(W/m²) |
Included sensors | 2 x identical ISO 9060 spectrally flat Class C pyranometer |
Mounting | ¾ inch NPS tube (not included) |
Calibration uncertainty | < 2.4 % (k = 2) |
Calibration traceability | to WRR |
Spectral range | 285 to 3000 x 10⁻⁹ m |
Rated operating temperature | -40 to +80 °C |
Temperature response | < ± 3 % (-10 to +40 °C) |
Standard cable length | 5 m (see options) |
Options
- longer cable, in multiples of 5 m
- sun screens
Albedo measurement
Albedo, also called solar reflectance, is defined as the ratio of the reflected to the global radiation. The solar albedo depends on the directional distribution of incoming radiation and on surface properties at ground level. Albedos of typical surfaces range from about 4 % for fresh asphalt, and 15 % for green grass to 90 % for fresh snow.
SRA01 Design
Using SRA01 is easy. The albedometer is composed of two pyranometers, the upfacing one measuring global solar radiation, the downfacing one measuring reflected solar radiation. The irradiance in W/m² in each direction is calculated by dividing the pyranometer output, a small voltage, by the sensitivity. The sensitivity of both pyranometers, model SR01, is provided on the SRA01 product certificate. The albedo is calculated by dividing the reflected radiation by the global radiation. The working principle and specifications of the pyranometers can be found in the SRA01 manual. SRA01 can be connected directly to commonly used datalogging systems.
Applications
Albedometers are used for general meteorological observations, building physics, roof reflectance studies, climate studies and solar collector testing. A common application is for outdoor solar radiation measurements as part of a meteorological station. This application requires horizontal levelling; a bubble level is included. SRA01 is made to fit a ¾ inch NPS mounting tube. SRA01 can be ordered with longer cable and optional sun screens
Suggested use
- agricultural networks
- general meteorological observations
- building physics, roof reflectance studies