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Comparison of the characteristics of small commercial NDIR CO2 sensor models and development of a portable CO2 measurement device.

Yasuda T, Yonemura S, Tani A - Sensors (Basel) (2012)

Bottom Line: When the correction was applied to the sensors, the accuracy of measurements improved significantly in the case of the K30 and AN100 units.In particular, in the case of K30 the relative RMS error decreased from 24% to 4%.This indicates that acceptable accuracy can be realized using the calibration method developed in this study.

View Article: PubMed Central - PubMed

Affiliation: Plant and Environmental Sciences, Department of Environmental Health Science, University of Shizuoka, Shizuoka Japan. p09402@u-shizuoka-ken.ac.jp

ABSTRACT
Many sensors have to be used simultaneously for multipoint carbon dioxide (CO(2)) observation. All the sensors should be calibrated in advance, but this is a time-consuming process. To seek a simplified calibration method, we used four commercial CO(2) sensor models and characterized their output tendencies against ambient temperature and length of use, in addition to offset characteristics. We used four samples of standard gas with different CO(2) concentrations (0, 407, 1,110, and 1,810 ppm). The outputs of K30 and AN100 models showed linear relationships with temperature and length of use. Calibration coefficients for sensor models were determined using the data from three individual sensors of the same model to minimize the relative RMS error. When the correction was applied to the sensors, the accuracy of measurements improved significantly in the case of the K30 and AN100 units. In particular, in the case of K30 the relative RMS error decreased from 24% to 4%. Hence, we have chosen K30 for developing a portable CO(2) measurement device (10 × 10 × 15 cm, 900 g). Data of CO(2) concentration, measurement time and location, temperature, humidity, and atmospheric pressure can be recorded onto a Secure Digital (SD) memory card. The CO(2) concentration in a high-school lecture room was monitored with this device. The CO(2) data, when corrected for simultaneously measured temperature, water vapor partial pressure, and atmospheric pressure, showed a good agreement with the data measured by a highly accurate CO(2) analyzer, LI-6262. This indicates that acceptable accuracy can be realized using the calibration method developed in this study.

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Comparison of CO2 concentration measured with the portable CO2 measurement device and LI-6262 on 7 February 2010.
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f8-sensors-12-03641: Comparison of CO2 concentration measured with the portable CO2 measurement device and LI-6262 on 7 February 2010.

Mentions: Owing to the response delay of the sensor in the developed device, the measured CO2 data had to be time-shifted to the CO2 data obtained with the LI-6262. Subsequently, the RRMS difference of the portable CO2 measurement device against the LI-6262 was calculated. The RRMS difference was 3.5%, indicating a good agreement of the outputs between the high-precision CO2 analyzer and the developed device (Figure 8).


Comparison of the characteristics of small commercial NDIR CO2 sensor models and development of a portable CO2 measurement device.

Yasuda T, Yonemura S, Tani A - Sensors (Basel) (2012)

Comparison of CO2 concentration measured with the portable CO2 measurement device and LI-6262 on 7 February 2010.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3376595&req=5

f8-sensors-12-03641: Comparison of CO2 concentration measured with the portable CO2 measurement device and LI-6262 on 7 February 2010.
Mentions: Owing to the response delay of the sensor in the developed device, the measured CO2 data had to be time-shifted to the CO2 data obtained with the LI-6262. Subsequently, the RRMS difference of the portable CO2 measurement device against the LI-6262 was calculated. The RRMS difference was 3.5%, indicating a good agreement of the outputs between the high-precision CO2 analyzer and the developed device (Figure 8).

Bottom Line: When the correction was applied to the sensors, the accuracy of measurements improved significantly in the case of the K30 and AN100 units.In particular, in the case of K30 the relative RMS error decreased from 24% to 4%.This indicates that acceptable accuracy can be realized using the calibration method developed in this study.

View Article: PubMed Central - PubMed

Affiliation: Plant and Environmental Sciences, Department of Environmental Health Science, University of Shizuoka, Shizuoka Japan. p09402@u-shizuoka-ken.ac.jp

ABSTRACT
Many sensors have to be used simultaneously for multipoint carbon dioxide (CO(2)) observation. All the sensors should be calibrated in advance, but this is a time-consuming process. To seek a simplified calibration method, we used four commercial CO(2) sensor models and characterized their output tendencies against ambient temperature and length of use, in addition to offset characteristics. We used four samples of standard gas with different CO(2) concentrations (0, 407, 1,110, and 1,810 ppm). The outputs of K30 and AN100 models showed linear relationships with temperature and length of use. Calibration coefficients for sensor models were determined using the data from three individual sensors of the same model to minimize the relative RMS error. When the correction was applied to the sensors, the accuracy of measurements improved significantly in the case of the K30 and AN100 units. In particular, in the case of K30 the relative RMS error decreased from 24% to 4%. Hence, we have chosen K30 for developing a portable CO(2) measurement device (10 × 10 × 15 cm, 900 g). Data of CO(2) concentration, measurement time and location, temperature, humidity, and atmospheric pressure can be recorded onto a Secure Digital (SD) memory card. The CO(2) concentration in a high-school lecture room was monitored with this device. The CO(2) data, when corrected for simultaneously measured temperature, water vapor partial pressure, and atmospheric pressure, showed a good agreement with the data measured by a highly accurate CO(2) analyzer, LI-6262. This indicates that acceptable accuracy can be realized using the calibration method developed in this study.

Show MeSH