Application & Field Experience with Metal Oxide Surge Arresters
Metal oxide surge arresters have become revolutionized in terms of application and expected performance in areas of higher stress levels. This has resulted in confidence in their reliability and offered new possibilities for overvoltage protection and improved management of power system disturbances. CIGRE Working Group A3.17 evaluated different stresses on MOSAs and also reviewed relevant test procedures, including investigation into the state of present designs. This presentation reviews the historical development of modern MOSAs and describes their interaction with system conditions and ambient stresses. The basics of the metal oxide material as well as of the various arrester designs on the market are also explained.