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7.6 Confirm that a fault exists
.
1
Remove the A-Frame from the ground.
2
Rotate it 180 degrees and re-insert it into the ground. The arrows should
reverse directions and point away from the ground spike.
7.7 Trace the cable with the 480B Receiver.
The 480B Line Locator allows you to trace the line and search for the fault at the same
time.
1
Check the 480B Receiver for cable tracing frequency. Aim the Receiver at the
Red lead and confirm that the tracing frequency is being received.
2
Trace and mark the cable as you proceed towards the fault.
7.8 Pinpoint the fault.
1
Keep the A-Frame parallel to the target cable
2
Insert the A-Frame every 10-20 feet. Follow the arrow and monitor the Active
number.
3
When locating with the A-Frame, make sure that the probes are inserted well
into the ground. A good physical ground connection is needed to receive
strong signal.
4
When the arrow changes direction, back track. Check the Active number and
compare it to the Reference number. If both Active and Reference numbers
have the same or similar value, you have found the major fault.
5
Insert the A-Frame every two feet until the arrow changes direction again, then
turn it 90 degrees. Check for obvious causes where a fault is suspected, such
as recent excavation.
6
Continue to move the A-Frame across the cable until a slight movement causes
the arrow to change directions. When this happens, the fault is located at the
center of the A-Frame.
7.9 Verify the fault.
1
Move slightly off to one side of the cable.
2
Insert the A-Frame into the ground at various positions around the suspected
fault site (like the hands of a clock).
3
The arrow should always point toward the fault.
4
Place the other spike in the ground at the fault site and repeat the process. The
arrow should always point inward, toward the fault
