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Acoustic pin-pointing – general
Acoustic pin-pointing is suitable for:
• High-resistive cable faults
• Cable and phase breaks
Basic principle
Surge voltage pulses are fed into the faulty phases of the cable, which lead to break-
downs at the fault. The breakdowns result in an acoustic and magnetic signal. The
dierent propagation times of the signals are compared: The magnetic signal prop-
agates almost at the speed of light and triggers a time measurement in the receiver.
The acoustic signal, which propagates only at the speed of sound, is detected by the
acoustic ground probe after a delay, whereupon the time measurement is stopped.
The dierence in propagation time between the signals is determined and displayed
as a distance from the fault location. The shorter the measured time, the closer is the
acoustic ground probe to the fault.
Required equipment
• Surge voltage generator (e.g. BAUR SSG)
• CU control unit, AGP acoustic ground probe, Bluetooth® headphones
protrac® pin-pointing system 822-186-4