CS IRGASON, Instruction Manual

Page: 15 / 74

IRGASON
®
Integrated CO
2
/H
2
O Open-Path Gas Analyzer and 3D Sonic Anemometer
3
These measurements are required to compute carbon dioxide and water vapor
fluxes using the:
• Standard outputs:
o u
x
, u
y
, and u
z
orthogonal wind components
o sonic temperature (based on the measurement of c, the speed of
sound)
o sonic diagnostic flags
o CO
2
density, H
2
O density
o gas analyzer diagnostic flags
o air temperature, air pressure
o CO
2
signal strength, H
2
O signal strength
o Air temperature and air pressure are auxiliary sensor inputs
Datalogger compatibility: CR6
CR1000
CR3000
CR5000
Measurement
Rate:
60 Hz
Output bandwidth 2 : 5, 10, 12.5, or 20 Hz
Datalogger-prompted
output rate: 1 to 60 Hz
Output rate 2 : 10, 25 or 50 Hz
Operating temperature: –30 to 50 °C
Gas analyzer
Measurement precision
1
CO
2
density: 0.2 mg · m –3 (0.15 µmol · mol –1 )
H
2
O density: 0.00350 g · m –3 (0.006 mmol · mol –1 )
Factory calibrated range
CO
2
: 0 to 1000 µmol · mol –1
H
2
O: 0 mmol · mol –1 to 37 °C dewpoint
Analyzer temp: –30 to 50 °C
Baro pressure: 70 to 106 kPa
CO
2
performance
Zero max drift 3 : ±0.55 mg · m –3 · °C –1 (±0.3 μmol · mol · °C –1 )
Gain Drift:
±0.1% of reading · °C –1 (maximum)
Sensitivity to H
2
O: ±1.1 x 10
–4
µmol CO
2
· mol
–1
H
2
O (max)
H
2
O performance
Zero max drift
3
: ±0.037 g · m
–3
· °C
–1
(±0.05 mmol · mol
–1
· °C
–1
)
Gain Drift: ±0.3% of reading · °C –1 (maximum)
Sensitivity to CO
2
: ±0.1 mol H
2
O · mol –1 CO
2
(maximum)
Sonic measurement precision
4
u
x
: 1 mm · s –1
u
y
: 1 mm · s –1
u
z
: 0.5 mm · s –1
Sonic temperature: 0.025 °C