Degradation of 230/400 V distribution cables with PVC insulation

Durability and reliability of cable lines is related to the quality of insulation materials, proper installation and maintenance during operation, as well as its mode of operation and not least by the action of degradation factors during operation. Neglecting any of these factors can significantly shorten the designed life or cause damage during operation. Producers in technical terms normally guarantee 20-30 years lifetime. Another serious problem is the so called synergistic effect, which occurs with action of several degradation factors superposition. The result may be different degree of insulation aging which would arise, if the individual stress act sequentially and individually. The paper presents the results of operation of water and cyclic thermal stress on the properties of the core insulation of the CYKY-J 4×16 cable.