Assessment of dielectric properties of cable insulation

Abstract

Absorption current measurements and very low frequency dielectric measurements were performed to evaluate the insulation properties of halogen free fire retardant cables at various temperatures. Changes of electrical parameters have been used for the cables characterization and comparison. The results of measurements proved a complex character of the dielectric phenomena, which consist of several independent processes with individual response to the temperature changes. In the paper a technique of dielectric measurements and analysis of their results was reviewed with emphasis on the range of very low frequencies. The measured and calculated parameters will be used in the future as a start point for evaluation of the cables ageing.