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Sheath fault location – general
Sheath fault location is suitable for:
• Low-resistive faults due to earth contact
• Cable sheath faults
Basic principle
A series of HV pulses are fed into the faulty cable. At the fault, the voltage pulses
discharge into the surrounding ground due to the fault resistance and form a voltage
gradient on the earth surface. The step voltage that can be measured on the earth sur-
face, rises in the direction of the fault and changes the polarity directly above the fault.
Required equipment
• HV generator (e.g. BAUR shirla)
• CU control unit, SVP step voltage probes
• To improve the contact between the SVPs and the ground for sheath fault location
on sealed surfaces (concrete, asphalt): canister of salt water, sponges
User interface
HV source
protrac® pin-pointing system 822-186-4