The SB-41A is a tin dioxide semiconductor gas sensor which has a high sensitivity to HFCs (e.g. Freon: R22) with improved cross sensitivity to other gases. This model is suitable for R22 and other new Freon family which contains R22.A significant feature of low power consumption design (120 mW) is advantageous for portable devices.
Structure
Gas sensitive semiconductor material is a mini bead type and a heater coil and electrode wire are embedded in the element. The sensing element is installed in the metal housing which uses double stainless steel mesh (100 mesh) in the path of gas flow.
Sensitivity characteristics
The sensitivity characteristics of the SB-41A is specified by the following parameters.
Sensor resistance level: at R22 1000 ppm
Sensor resistance change Ratio: between R22 300 ppm and 1000 ppm
Sensor resistance change ratio: between clean air and R22 300 ppm