Measurement of Relative Humidity Using Electrochemical Sensors

Highly sensitive and accurate determination of relative humidity of technical gases is required in many branches of human activities (health care, food packing, etc.). In this paper, a new series of electrochemical sensors manufactured by BVT Technologies is introduced; they measure changes in conductivity of hygroscopic materials with changing content of water vapour in ambient gas. The main topics of the contribution focus on a description of the physical principles of these electrochemical sensors taking advantage of a hygroscopic layer, sensor arrangements, sensor signal processing and electronic equipment architecture. Achieved results and errors analysis are discussed in detail.