By using a transmitter to place a signal with a certain frequency on the pipeline, the CP-interference can be localised above-ground and followed with the aid of a receiver. If the signal suddenly drops or if it deviates from the exact location of the pipe as indicated on the underground area drawing, there may be a CP-disturbance at this location.
The next step is to then excavate the detected location for a visual inspection. If a CP-breakdown is found, the disturbance has to be fixed by electrically separating the pipe and the third object(s), for example by using PE-strips.
