The invention relates to a real-time measuring
system for changes of an
electric potential on the surface of an insulating material. The
system comprises a pedestal, a probe and
electrode fixing support, a slide rail scale, a prober holder, a supporting column, a high-
voltage electrode, a ground
electrode, a
capacitance probe, a probe protective cover, an insulating material fixing groove, a static
voltmeter, a
data acquisition system, a data process system, and a display interface. The probe and electrode fixing support is fixed above the pedestal through the supporting column. A slide guide rail is arranged on the fixing support. The high-
voltage electrode, the probe protective cover and the probe holder are vertically arranged on the fixing support in sequence. The upper end of the
capacitance probe is connected to the static
voltmeter. The ground electrode is fixed to the pedestal. The insulating material fixing groove is arranged on the pedestal. The static
voltmeter, the
data acquisition module, the data process system and the display interface are connected in sequence. The system can measure on-line in real time electric potentials on the surfaces of different
solid insulating materials and the same kind of
solid insulating materials at DC voltages as well as in a power-off condition after
surface modification.