Vaisala GMP252 - Environmental Compensation; Figure 4 CO 2 Measurement in the Measurement Cuvette

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Figure 4 CO
2
Measurement in the
Measurement Cuvette
1 Gold-plated mirror
2 Light absorbed by CO
2
in the measured
gas
3 Hermetic window
4 Fabry-Pérot interferometer
5 Light source (Microglow)
6 Hermetic window
7 Thermopile detector
2.4 Environmental Compensation
When necessary, various environmental compensations can be applied to improve the CO
2
measurement accuracy of the probe.
The probe can compensate for the eects of the following parameters:
• Temperature
• Pressure
• Background gas oxygen (O
2
) content
• Background gas relative humidity (%RH)
To apply an accurate relative humidity compensation, make sure that also the temperature
compensation and pressure compensation
configurations match the measurement
environment.
The probe has an on-board temperature sensor that can be used to compensate for
temperature. Additionally, if the probe is integrated in a system that measures one or more
of the compensation parameters (T, P, RH, O
2
), they can be updated to the probe
continuously.
Chapter 2 – Product Overview
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