Optical sensor for ozone detection in Medium Voltage switchboard

The application of a fibre optic sensor for ozone detection in MV switchboard is evaluated. The sensor is based on the differential measure of the absorption in UV and visible spectral bandwidths. The layout exploits the use of an optical retro-reflector, to improve the detection sensitivity. Preliminary tests were performed in comparison with another calibrated system to assess the sensitivity and the linearity of the innovative sensor (0.1-10 ppm). Further results of tests carried out on a laboratory mock-up simulating predischarge phenomena are discussed confirming the compliance of the main features of the assembled system with application requirements.