A review of methods for condition monitoring, surveys and statistical analyses of disconnectors and circuit breakers

There is a need for a new survey of condition-monitoring methods for circuit breakers and disconnectors, since during the last two decades less than ten surveys have been carried out. The paper presents several statistical surveys and analyses. The methods of condition monitoring found are reviewed and classified according to the different types of failure identified in the surveys. Some research gaps are identified, such as the prediction of the degradation of the contacts, the signal processing of coil and motor currents and the switching.