Patent ID: 6236218
Filing Date: 2001-05-22
Classification: G01R

Abstract:
A method for space-charge measurement in a coaxial cable having an inner conductor, a cable screen and an electric insulation between the inner conductor and the cable screen, comprising the steps of:removing the cable screen on both sides of a measurement range,generating an electric voltage pulse by an electric pulse generator,applying the pulse over part of the insulation of the cable within the measurement range,generating an acoustic signal, in the presence of space charges in the cable insulation, by the voltage pulse in cooperation with the space charges andrecording any sensible acoustic signal by a sound-recording device, including disposing a grounded annular outer electrode around the measurement range, arranging the sound-recording device in direct contact with the annular outer electrode, and applying the voltage pulse to the cable screen on both sides of the measurement region and, connecting the pulse to the inner conductor of the cable via the impedance of the cable such that a pulse-shaped voltage will lie between the inner conductor of the cable and the annular outer electrode.