Oxygen Gas Sensors

An Oxygen or Gas sensor is an electronic device that measures the proportion of oxygen in the gas or liquid being tested. The original sensing element is made with zirconia ceramic coated in the form of a thimble shape. These were coated on both exhaust and reference sides with a thin layer of platinum and comes in both unheated and heated form. The most common application of this type of sensor is in the automotive industry to measure the exhaust gas concentration of oxygen for the engines. The probe sensor element itself is a ceramic cylinder plated inside and out with porous platinum electrodes and the whole assembly is then housed in a metal gauze. It works by measuring the difference in oxygen between the exhaust gas and external air, and then generates a voltage or changes its resistance depending on the difference between the two.