The measurement of water tree growth in cross-linked polyethylene cables

Discusses measurements of tree growth on full scale production cables. In this paper an ageing system is reported in which water trees have been grown in short lengths of production cable. Using this measuring system a wide variety of controlled experiments has been made on ideal samples, cheaply and in a relatively small laboratory area. Both vented and bow-tie tree growth have been measured in triple extruded core over a range of times up to 1800 hours. The effect of various surface conditions has been determined. A comparison is made with measurements of trees grown in other geometries moulded in the laboratory