The invention discloses a method for testing
conductivity of medium material, wherein the method comprises the following steps of: positioning an
electric potential probe at a zero
electric potential position above a sample after the preparation before testing is finished; confirming the placing position of the sample, confirming the position coordinate of an
electric potential measuring point bya probe driving mechanism, then closing a vacuum
jar, turning on the power of an electric gun, and performing electronic
irradiation to the sample via a Faraday
cut test; quickly descending an electric potential meter probe to the front surface of the sample every 10 minutes to perform inducted non-contact measurement, wherein the data measured by a micro
galvanometer and the electric potential probe is waved between negative 0.5% and positive 0.5%, then the charge of the sample is regarded as saturation; turning off the electric gun, attenuating the similar process via a tapping index form in the sample interior
electric charge Q and measuring the electric potential decay process of the sample; in a word, the attenuation relationship of the surface electric potential of the sample along time is measured by a surface electric potential probe, and the
conductivity of the sample can be calculated according to the sample surface attenuated electric potential at different time. The
conductivity testing equipment in the invention can be applied to
hazard assessment of deep charging, and also can provide valuable
engineering data for the protection of deep charging or discharging.