Thermal Effects on Crosstalk of Multiconductor PVC Cables and Estimation of Thermal Accelerating Ratios

This article is concerned with how crosstalk amplitudes of multiconductor polyvinyl chloride cables vary with heating temperatures and time to determine thermal effects on the cables in realistic conditions and thus proposes a method to estimate aging rates and accelerating ratios with respect to the variation of crosstalk amplitudes. First, the mechanism of thermal effects on the crosstalk of multiconductor cables is analyzed: high temperatures accelerate chemical reactions in insulating materials to change their microstructures as well as their permittivity. The resulting variation of permittivity leads to changes in crosstalk amplitude. Then, experiments are conducted to measure crosstalk amplitudes of cables in a thermal chamber. Finally, based on measured results, time-based variations of crosstalk amplitudes at different temperatures are demonstrated and the equivalent chemical reaction rates are calculated. By fitting the rates with the Arrhenius equation, accelerating ratios between different temperatures are obtained.