Przetwornik do pomiaru stȩżeń gazów w mieszaninie gazowej

Gas sensors are widely applied in gas detectors. In such application a good metrological properties are not essential. In measuring devices, however, good metrological properties are very important. Good linearity of calibration curve, small sensitivity to additional quantities (including other gasses) are required. Unfortunately such properties are not typical for gas sensors. In this paper an measuring transducer of methane and carbon monoxide concentrations in gas mixture is proposed. Two sensors of FIGARO type 3870 and 2442 and integrated humidity and temperature sensor SHT75 are applied. The gas sensors were investigated - calibration curves and influences of other mentioned quantities were determined. The calibration data allowed to create a mathematical model for reconstruction of gases concentration in mixture. Conditioning circuits for both sensors are presented, too.