The effect of electric stress on the life of cables incorporating a polythene dielectric

Work on the voltage characteristics of polythene cables has been described in a previous paper; the present paper gives the results of further studies. Factors contributing to the breakdown of polythene cables have been investigated, and tests on cables have been supplemented with a similar series of tests on artificially produced voids. Voltage/life characteristics of cables with solid dielectric and a single non-stranded conductor have been examined, and voltage ratings, based on experimental work, are proposed for alternating and direct stresses.