Sensoric Toxic Gas Sensors (Mini, Classic, Smart, 4-Series, 7-Series)

Electrochemical toxic gas sensors are micro fuel cells, designed to be maintenance-free and stable for long periods. They have a direct response to volume concentration of gas rather than partial pressure. The simplest form of electro-chemical toxic sensor comprises two electrodes: sensing and counter, separated by a thin layer of electrolyte. This is enclosed in a plastic housing that has a small capillary to allow gas entry to the sensing electrode and includes pins which are electrically attached to both electrodes and allow easy external interface. These pins may be connected to a simple resistor circuit that allows the voltage drop resulting from any current flow to be measured (figure 1). Gas diffusing into the sensor is either oxidized or reduced at the sensing electrode and, coupled with a corresponding (but converse) counter reaction at the other electrode, a current is generated through the external circuit. Since the rate of gas entry into the sensor is controlled by the capillary diffusion barrier, the current generated is proportional to the concentration of gas present outside the sensor and gives a direct measure of the toxic gas present.

Availability: Commercially Available