Apogee SP-214 소유자 매뉴얼 - 페이지 13

{카테고리_이름} Apogee SP-214에 대한 소유자 매뉴얼을 온라인으로 검색하거나 PDF를 다운로드하세요. Apogee SP-214 18 페이지. Pyranometer
Apogee SP-214에 대해서도 마찬가지입니다: 소유자 매뉴얼 (19 페이지)

Sensor Calibration

All Apogee un-amplified pyranometer models have a standard calibration factor of exactly:

Multiply this calibration factor by the measured mV signal to convert sensor output to shortwave radiation in units of W m

Calibration Factor (5.0 W m

5.0

Full Sunlight

(1000 W m

Spectral Errors for Measurements with Silicon-cell Pyranometers

Apogee SP series pyranometers are calibrated under electric lamps in a calibration laboratory. The calibration procedure

simulates calibration under clear sky conditions at a solar zenith angle of approximately 45°. However, due to the limited

spectral sensitivity of silicon-cell pyranometers compared to the solar radiation spectrum (see graph below), spectral errors

occur when measurements are made in conditions that differ from conditions the sensor was calibrated under (e.g., the solar

spectrum differs in clear sky and cloudy conditions, thus measurements in cloudy conditions result in spectral error because

sensors are calibrated in clear sky conditions).

5.0 W m

per mV) * Sensor Output Signal (mV) = Total Shortwave Radiation (W m

-2

200

-2

)

Sensor Output

200 mV

-2

per mV

1000

Example of total shortwave radiation measurement with

an Apogee SP-110 pyranometer. Full sunlight yields total

shortwave radiation on a horizontal plane at the Earth's

surface of approximately 1000 W m

output signal of 200 mV. The signal is converted to

shortwave radiation by multiplying by the calibration

factor of 5.0 W m

-2

per mV.

-2

)

-2

. This yields an