Working principle of hydrogen sulfide detector
As is well known, hydrogen sulfide gas is very dangerous, not only explosive, but also highly toxic. Therefore, in order to detect hydrogen sulfide, it is necessary to be fast and accurate. At this time, a hydrogen sulfide detector is needed for detection. So how much do you know about the working principle of hydrogen sulfide detectors?
Working principle of hydrogen sulfide detector:
The hydrogen sulfide gas detector uses an electrochemical sensor, usually consisting of three electrodes immersed in the electrolyte. The working electrode is made by coating a metal with catalytic activity on a breathable but hydrophobic membrane.
The measured gas diffuses through a porous membrane and undergoes electrochemical oxidation or reduction reactions on it. The properties of the reaction depend on the thermodynamic potential of the working electrode and the electrochemical (oxidation or reduction) properties of the analyzed gas. In electrochemical reactions, electrons participating in the reaction flow into (reduce) or out (oxidize) the working electrode. The working signal of the working electrode is amplified by the operational amplifier U2 to become the output signal of the instrument.
The circuit maintains the voltage of the working electrode at its bias voltage VBIAS, while the reference electrode provides a stable potential for the working electrode in the electrolyte. After comparing the reference electrode potential with VBIAS, the output voltage signal of the operational amplifier U1 is exactly the same as generating a current signal that is equal to and opposite to the working electrode.
The working principle of the hydrogen sulfide detector mentioned above is shared here. The main function of the hydrogen sulfide detector is to detect the concentration of hydrogen sulfide gas in the air. When the concentration in the air reaches a certain level, the hydrogen sulfide gas detector will automatically sound and light an alarm, reminding staff to take corresponding measures in a timely manner to avoid major accidents.
