Electric strength measurements for quality control of EPR compound for high voltage cables

The results of a test procedure aiming at quality control of EPR to be used for high-voltage cable insulation are described in this paper. The electric strength is the property chosen as significant for assessing the quality of the product. Samples were obtained by random choice from compounds manufactured at different times. Moreover, in order to check appropriately the significance of the data variance, samples of improved and worsened quality were considered. The effect of specimen thickness is also investigated. It is shown that electric strength measurements can provide useful information on the quality of the pellets of a box which is going to be used for cable production.