Cable-fault location by impulse-current method

The paper presents a new approach to cable-fault location based on the use of high-voltage impulse generators. It is shown that, when an impulse generator is connected onto a faulty cable, the waveform of the generator output current can be used to determine the position of a fault. Several advantages are gained by the use of a linear coupler to provide the signal to the instrumentation, and it is shown that the signal also indicates whether or not an acoustic signal is being produced at the fault. The nonlinear characteristics of faults, which introduce errors and complications into most existing methods of fault location, are fully exploited with the new technique. Digital transient recorders are shown to have many advantages over the currently used methods of recording impulse waveforms. The information stored in the memory of a transient recorder can be easily transmitted to another location for interpretation by an experienced engineer. The more complex waveforms obtained on multibranched networks would be interpreted with the aid of a computer. It is suggested, that both the hardware and software being developed for cable-fault location purposes will also find application in the growing field of diagnostic testing.