Integrated CO2 and H2O Open-Path Gas Analyzer and 3-D Sonic Anemometer
Campbell Scientific’s IRGASON® fully integrates the open-path analyzer and sonic anemometer. Designed specifically for eddy-covariance carbon and water flux measurements, the patented design is easier to install and use than separate sensors and provides increased measurement accuracy. The IRGASON® simultaneously measures absolute carbon dioxide and water vapor, air temperature, barometric pressure, three-dimensional wind speed, and sonic air temperature. U.S. patent D680455
For more information about the benefits of having a colocated measurement, refer to the poster “Improved eddy flux measurements by open-path gas analyzer and sonic anemometer co-location.”
Benefits and Features
- Combined support structure causes less flow distortion than two separate sensors
- Truly colocated gas analyzer and sonic anemometer measurements avoid flux loss due to sensor separation
- Synchronized gas analyzer and sonic anemometer measurements avoid the need to correct for time lag
- Low power consumption; suitable for solar power applications
- Measurements are temperature compensated without active heat control
- Low noise
- Maximum output rate of 60 Hz with 20 Hz bandwidth
- Angled windows shed water and are tolerant to window contamination
- Field rugged
- Field serviceable
- Factory calibrated over wide range of CO2, H2O, pressure, and temperature in all combinations encountered in practice
- Extensive set of diagnostic parameters
- Fully compatible with Campbell Scientific dataloggers; field setup, configuration, and field zero and span can be accomplished directly from the datalogger
- Sonic temperature determined from three acoustic paths; corrected for crosswind effects
- Innovative signal processing and transducer wicks considerably improve performance of the anemometer during precipitation events
Specifications
Patent | U.S. Patent No. D680455 |
Operating Temperature Range | -30° to +50°C |
Calibrated Pressure Range | 70 to 106 kPa |
Input Voltage Range | 10 to 16 Vdc |
Power | 5 W (steady state and power up) at 25°C |
Measurement Rate | 60 Hz |
Output Bandwidth | 5, 10, 12.5, or 20 Hz (user-programmable) |
Output Options | SDM, RS-485, USB, analog (CO2 and H2O only) |
Auxiliary Inputs | Air temperature and pressure |
Warranty | 3 years or 17,500 hours of operation (whichever comes first) |
Cable Length | 3 m (10 ft) from IRGASON® to EC100 |
Weight |
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Gas Analyzer | |
Path Length | 15.37 cm (6.05 in.)
A temperature of 20°C and pressure of 101.325 kPa was used to convert mass density to concentration. |
Gas Analyzer – CO2 Performance | |
-NOTE- | A temperature of 20°C and pressure of 101.325 kPa was used to convert mass density to concentration. |
Accuracy |
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Precision RMS (maximum) | 0.2 mg/m3 (0.15 μmol/mol)
Nominal conditions for precision verification test: 25°C, 86 kPa, 400 μmol/mol CO2, 12°C dewpoint, and 20 Hz bandwidth. |
Calibrated Range | 0 to 1,000 μmol/mol (0 to 3,000 μmol/mol available upon request.) |
Zero Drift with Temperature (maximum) | ±0.55 mg/m3/°C (±0.3 μmol/mol/°C) |
Gain Drift with Temperature (maximum) | ±0.1% of reading/°C |
Cross Sensitivity (maximum) | ±1.1 x 10-4 mol CO2/mol H2O |
Gas Analyzer – H2O Performance | |
-NOTE- | A temperature of 20°C and pressure of 101.325 kPa was used to convert mass density to concentration. |
Accuracy |
|
Precision RMS (maximum) | 0.004 g/m3 (0.006 mmol/mol)
Nominal conditions for precision verification test: 25°C, 86 kPa, 400 μmol/mol CO2, 12°C dewpoint, and 20 Hz bandwidth. |
Calibrated Range | 0 to 72 mmol/mol (38°C dewpoint) |
Zero Drift with Temperature (maximum) | ±0.037 g/m3/°C (±0.05 mmol/mol/°C) |
Gain Drift with Temperature (maximum) | ±0.3% of reading/°C |
Cross Sensitivity (maximum) | ±0.1 mol H2O/mol CO2 |
Sonic Anemometer – Accuracy | |
-NOTE- | The accuracy specification for the sonic anemometer is for wind speeds < 30 m s-1 and wind angles between ±170°. |
Offset Error |
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Gain Error |
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Measurement Precision RMS |
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Speed of Sound | Determined from 3 acoustic paths (corrected for crosswind effects) |
Rain | Innovative signal processing and transducer wicks considerably improve performance of the anemometer during precipitation events. |
Basic Barometer (option -BB) | |
Total Accuracy |
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Measurement Rate | 10 Hz |
Enhanced Barometer (option -EB) | |
Manufacturer | Vaisala PTB110 |
Total Accuracy | ±0.15 kPa (-30° to +50°C) |
Measurement Rate | 1 Hz |
Ambient Temperature | |
Manufacturer | BetaTherm 100K6A1IA |
Total Accuracy | ±0.15°C (-30° to +50°C) |