Some remarks regarding the test cells used for electric strength measurements

This paper deals with the influence of the test cell on the results of electric strength measurements performed on polymeric materials. Two different types of electrodes are considered, i.e. rods and Pseudo-Rogosky configurations, surrounded by different media, that is, oil, SF6, and epoxy resin. An Ethylene-Propylene-Rubber (EPR)-based insulation was tested, in the form of flat specimens having different thickness. The results show that the scale and shape parameters of the two-parameter Weibull function employed to fit the breakdown data significantly changes when different specimen thickness, surrounding media and types of electrodes are used