Commercial H 2 s sensor based on SnO 2 :CuO thin films

In the present work, a commercial device for the detection of H 2 S using SnO 2 ; CuO thin film as a sensing material has been demonstrated. A complete device consist of SnO 2 : CuO sensor thin film deposited on alumina substrate, teflon head in stainless steel housing containing the temperature control circuit with Pt-50 based heater and Pt-100 as reader, and a stand-alone monitor consisting of Data Acquisition & Control Board (DACB) and touch screen based human-machine interface (HMI) module. The monitor measures the change in resistance of sensor element on exposure to gas and displays the result in concentration (ppm). The monitor is also provided with a programmable alarm set point, touch switch to change between Normal/ Calibration Mode and provision to enter the historical logs like last sensor installation date, last sensor calibration date, last fault detail etc,.