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8.2 Faults Under Pavement
Faults under pavement or other slightly conductive surfaces can be found using the foam
pads supplied with the unit. Saturate the pads with water and insert the A-Frame spikes
into the pads. Locate the fault as you normally would. Be sure to keep the pads as moist
as possible, but do not let the water form a continuous puddle between the pads as this
will short out the signal.
8.3 Long Distance Tracing.
As the distance to the fault increases, the signal picked up by the A-Frame is
proportionally reduced. This condition can lead to problems if the signal levels are
reduced to the point that they can no longer be detected by the A-Frame.
Whenever working with weak signals due to long distance faults (or other reasons),
increased sensitivity can be obtained by extending the distance between the A-Frame
spikes using the extension cable. This extension method can be applied to any of the
previously discussed methods including the conductive foam pads. When working with
very long distances, as in fiber optic runs, the sensitivity can be increased even further
using a longer insulated wire to extend the A-Frame span. See
Figure 8-4
.
Figure 8-4: Fault Location Using Extension Cable for Increased Sensitivity
