What type of sensors are used in instruments?
Most of the sensors used in madur flue-gas analysers are of the electrochemical type. The major elements of Toxic Gas electrochemical sensors are three coated electrodes (sensing, counter, and reference) and a small volume of an acidic or alkaline solution. In use, the gases diffuse through an orifice on the sensing face of the sensor onto the electrode surface and cause a small electrical current. This current is amplified and measured by the electronics. The measured value is then displayed and available for printing, storing or downloading to a computer. In its simplest form, a sensor operating on electrochemical principles requires two electrodes x a sensing and a counter x separated by a thin layer of electrolyte. Gas diffusing to the sensing electrode reacts at the surface of the electrode either by oxidation or reduction. This reaction causes the potential of the electrode to rise or fall with respect to the counter electrode. With a resistor connected across the electrodes, a c
