Fault-locator for use in locating high-resistance ground faults in or on concentric-ground electrical power cables

摘要

Faults in electrical coaxial power cables are detected by transmitting a pulsed signal into the cable at a frequency of 512 Hz at an amplitude of the order of 4000 volts peak-to-peak. The capacitance of the cable is adjusted by a separate capacitive tuning box to generate a parallel resonant condition between the transmitter and the cable. These parameters create a condition in which the resistive current generated by the fault is larger than the capacitive/reactive current per foot of the cable enabling detection of the fault by a manually transported receiver dedicated to the frequency of the transmissions.