Apogee Instruments SP-722-SS, Руководство оператора

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SPECIFICATIONS
Calibration Traceability
The pyranometers on Apogee Instruments model SP-722 albedometers are calibrated through side-by-side
comparison to the mean of four Apogee model SP-510 transfer standard pyranometers (shortwave radiation
reference for upward-looking pyranometer on albedometer) or to the mean of four Apogee model SP-610 transfer
standard pyranometers (shortwave radiation reference for downward-looking pyranometer on albedometer)
under high intensity discharge metal halide lamps. The transfer standard pyranometers are calibrated through
side-by-side comparison to the mean of at least two ISO-classified reference pyranometers under sunlight (clear
sky conditions) in Logan, Utah. Each of four ISO-classified reference pyranometers are recalibrated on an
alternating year schedule (two instruments each year) at the National Renewable Energy Laboratory (NREL) in
Golden, Colorado. NREL reference standards are calibrated to the World Radiometric Reference (WRR).
SP-722-SS (Upward-looking) SP-722-SS (Downward-looking)
ISO 9060:2018 Class C N/A
Power Supply 5.5 to 24 V
Current Draw
Heaters off: ≈ 5 mA
Heaters on: ≈ 31 mA
Calibration Uncertainty ± 5 % (see Calibration Traceability below)
Measurement Range 0 to 2000 W m -2 (shortwave irradiance)
Measurement Repeatability Less than 1 %
Long-term Drift (Non-stability) Less than 2 % per year
Non-linearity Less than 1 %
Field of View 180° 150°
Spectral Range (wavelengths where
response is 50% of maximum)
385 to 2105 nm 370 to 2240 nm
Directional (Cosine) Response
Less than 30 W m
-2
at 80° solar zenith
Less than 20 W m
-2
for angles
between 0 and 60°
Temperature Response Less than 5 % from -15 to 45 C
Zero Offset A
Less than 2 W m -2 ; Less than 10 W
m
-2
(heated)
Less than 1 W m -2 ; Less than 5 W m -2
(heated)
Zero Offset B Less than 5 W m
-2
Uncertainty in Daily Total Less than 5 %
Operating Environment -50 to 80 C; 0 to 100 % relative humidity
Heater 390 Ω, 30.8 mA current draw and 370 mW power requirement at 12 V DC
Dimensions 66.5 mm height, 74.4 mm length, 33 mm width
Mass 247 g