Electrical field grading material and use thereof in electrical cable accessories

Abstract

Electrical field grading material which comprises a non-polar elastomeric polymer, a phyllosilicate filler and a carbon black filler, wherein any carbon black filler present in the electric field grading material has a dibutyl phthalate (DBP) absorption number from 30 to 80 ml/100 g. The above material may be used in electrical cable accessories, particularly electrical cable joints or terminations for medium or high voltage cable. The electrical field grading material according to the present invention has varioresistive properties, particularly a significant variation of electrical conductivity as a function of the applied voltage within a reduced voltage range, so as to guarantee a high value of conductivity above a critical value of the electrical field, and therefore to ensure an even distribution of the electrical field lines within the material.

Dependencies are inferred from the claim text.