Quality of accessory components and jointing for medium voltage extruded insulation cables

UNIPEDE DISCAB undertook a fault statistics survey on accessories for MV extruded insulation cables but found it impossible to provide any coherent picture from the survey results. Much later, the Nordic countries sponsored a comparison of accessory performance. All the current technologies were represented. It was clear from this study that accessories behaved well but the accessories that gave problems in the tests were those that contained jointing errors. A Belgian study concluded that there were problems with connectors. Following discussion in UNIPEDE DISCAB, over several meetings, where members regularly provide reports on performance it was recognised that several accessory technologies now perform well, but there is still a problem in ensuring quality in jointing. It was therefore decided that a survey should be undertaken to elicit answers as to the background, specification and training for quality in accessories. A draft questionnaire was prepared within DISCAB and sent out in August 1997. Sixteen responses were received. Although this is not a comprehensive result, it nevertheless provides important insights on good practice. The results are discussed.