Applicability of resistance and temperature measurements for the characterization of full tension compression splices

Overhead transmission lines are built using a multitude of different components. The ability of transmission lines to transmit energy will depend strongly on the reliability of each of these components. Compression splices are one of the important links in this chain of elements. Like many electric utilities worldwide, Hydro-Quebec considers the on-line inspection of splices to be necessary to better evaluate the network´s condition and reliability. There are two methods used to characterize splices: measuring the electrical resistance and/or measuring the temperature. As part of a research project aimed at assessing the residual life of line equipment, Hydro-Quebec have evaluated the two methods on samples taken from in-service equipment by using an Ohmstick^TM instrument and a FLIR 760 radiometric imaging system. This paper presents a quantitative and comparative evaluation of the performance and limitations of both techniques as regards their on-line applicability for splice characterization.