Diagnostic Testing for Assessment of Distribution Cables

Distribution network system owners and managers are increasingly more conscious on the significance of their ability to improve the condition and reliability of their network system. A combination of pertinent diagnostic testing are sought after for condition assessment. Adoption of the most appropriate diagnostic system between the one that are already developed and practiced and others that are promising but still in development is not an easy task to achieve. Installations of MVUG in TNB network system basically consist of PILC, XLPE, and mixed (PILC and XLPE) cables. The PILC cables were the first to be introduced. The XLPE cables came in the late 1980s. Currently only XLPE cables are used for new installation but limited length of PILC cables are still kept for maintenance purposes. The voltage levels for the underground cable network system are 11 kV, 22 kV, and 33 kV. At these voltage levels, the total lengths as of year 2004 are roughly 289,000 km for PILC cables and 257,000 km for XLPE cables. The performance of PILC cable is important in terms of supply reliability as its total length is still significant in the network. Therefore, monitoring the condition of these cables is considered very important and has to be looked into seriously