Temperature effects on the electrical conductivity of dielectric liquids

The effect of temperature on electrical conductivity of low-conductivity liquid solutions is discussed theoretically and experimentally. A well-known expression for liquid viscosity is used to derive an empirical correlation for temperature dependency of electrical conductivity of insulating liquids. Five different solutions all composed of polyol (hindered) esters were tested over a wide temperature range. Viscosity measurements were used to extract the constants in the viscosity correlation. The measured electrical conductivity of the tested fluids varied over 1000-fold for the temperature range. It is shown that the suggested correlation could predict reasonably well the temperature dependency of electrical conductivity for single-phased solutions.