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Apogee SN-500 Net Radiometer
The new Apogee Instruments SN-500 four-component net radiometer features SDI-12 output. Shortwave (Pyranometers): 385nm to 2105nm (upward looking); 295 to 2685 nm (downward-looking); (50 % points) Longwave (Pyrgeometers): 5 to 30 ?m (50 % points) The detectors have a linear response (less than 1% nonlinearity) in the following ranges: Net shortwave: 0 to 2000 W m-2 Net longwave: -200 to 200 W m-2 Four-component Net Radiometer An upward-looking and downward-looking pyranometer, and an upward-looking and downward-looking pyrgeometer provide separate measurements of the four components of net radiation. Onboard A/D Conversion and SDI-12 Output Apogee net radiometers feature onboard A/D conversion and SDI-12 output to eliminate the requirement of multiple analog datalogger channels. Individually Heated Radiometers Each radiometer includes an individual heater to increase accuracy by minimizing the influence of dew, frost and snow on the filter. Compact and Light Weight Designed to be light weight and small in size to facilitate easy mounting. Cost-effective Apogee’s net radiometer is low cost compared to other four-component net radiometers on the market.
Net radiation is the sum of the four components shown above (incoming shortwave, outgoing shortwave, incoming longwave, outgoing longwave). Incoming shortwave incident on the surface is either reflected or absorbed by the surface material, and longwave radiation is emitted from the surface and emitted from the molecules of air in the atmosphere. Typical clear sky summer fluxes over grass and clear sky winter fluxes over snow are shown. A typical summer flux at solar noon would be +650 W/m2; in winter it would be 0 W/m2.
Enabling better global research outcomes in soil, plant & environmental monitoring. www.ictinternational.com :
[email protected] : +612 6772 6770
Apogee SN-500 Net Radiometer
Specifications SL-500 Series Sensitivity
0.10mV per W m-2 (variable from sensor to sensor, typical value listed)
Calibration Factor (Reciprocal of Sensitivity)
10W m-2 per mV
Temperature Dependence
TBD
Calibration Uncertainty
±5%
Measurement Range
-200 to 200 W m2 (net longwave irradiance)
Measurement Repeatability
less than 1%
Zero Offset
TBD
Long-term Drift
less than 2% change in sensitivity per year
Non-linearity
TBD
Response Time
less than 0.2s
Field of View
150°
Tilt Error
TBD
Spectral Range
5 to 30 µm (wavelengths where response is 50% of maximum)
Operating Environment
-50 to 80°C
Temperature Sensor
30 k? thermistor, ±1°C tolerance at 25°C
Output from Thermistor
0 to 2500 mV (typical, other voltages can be used)
Input Voltage Requirement for Thermistor
2500 mV excitation (typical, other voltages can be used)
Heater
780?, 15.4mA current drain and 185mW power requirement at 12V DC
SP-500 Series Sensitivity
0.055mV per W m-2 (Upward-looking); 0.15 mV per W m-2 (Downward-looking); (variable from sensor to sensor, typical values listed)
Calibration Factor (Reciprocal of Sensitivity)
18.2 W m-2 per mV (upward-looking); 6.67 W m-2 per mV (downward-looking)
Calibration Uncertainty
±5%
Measurement Repeatability
less than 1%
Long-term Drift
less than 2% per year
Non-linearity
TBD
Response Time
Less than 0.2s
Enabling better global research outcomes in soil, plant & environmental monitoring. www.ictinternational.com :
[email protected] : +612 6772 6770
Apogee SN-500 Net Radiometer
Field of View
180° (upward-looking); 150° (downward-looking)
Spectral Range
385nm to 2105nm (upward-looking); 295 to 2685nm (downward-looking); (wavelengths where response is 50% of maximum)
Directional (Cosine) Response
TBD
Temperature Response
TBD
Operating Environment
-50 to 80°C; 0 to 100% relative humidity.
SN-500 Input Voltage Range
5-16V DC (Heaters designed to run at a nominal 12V DC)
Current Draw (12V DC Supply Voltage)
Heaters On and Taking Measurement: 62mA; Heaters On: 61mA; Heaters Off and Taking Measurement: 1.5mA; Heaters Off: 0.6mA
Response Time (using SDI-12 Protocol)
1s
Dimensions
116.0mm length and 66.0mm height
Mass
90g (with mounting rod and 5m of lead wire)
Enabling better global research outcomes in soil, plant & environmental monitoring. www.ictinternational.com :
[email protected] : +612 6772 6770
Apogee SN-500 Net Radiometer
Enabling better global research outcomes in soil, plant & environmental monitoring. www.ictinternational.com :
[email protected] : +612 6772 6770 Powered by TCPDF (www.tcpdf.org)
