Condition based maintenance of PE/XLPE-insulated medium voltage cable networks-verification of the IRC-analysis to determine the cable age

For a preventive maintenance and a more economical operation of polymer insulated cable networks a destruction free estimation of the status of laid PE/XLPE-cables is a basic need. This contribution presents a condition based maintenance concept with the IRC-Analysis applied on a part of the 20 kV-cable network of a major German utility. With this concept the distributor was able to reduce the amount of insulation failures-especially for cables manufactured before 1984. The general tendency of increasing faults was broken and a higher quality of energy supply was achieved.