Leica Ultra User Manual page 87

Finding general loca-
tion of a faulted cable
Fault locating concepts
Ultra, Fault Finder on Ultra Advanced
Some things to look for when searching for the general location of a faulted cable are:
• Recently disturbed soil
• Past splices
• "Buried utility" notices
• Utility facilities without overhead lines
Isolating the cable on both ends and then energizing it with a special signal generated by a
transmitter creates an electrical circuit where current flows down the cable and seeks a path
back to the transmitter. The path back to the transmitter is along the path of the fault to
ground. Current will not flow without a path to ground.
Use a fault probe to probe the earth and measure the signal along the path of the cable.
Signal will be highest at the point of the fault where the current enters the ground and at
the transmitter ground stake. The arrows on the locator point toward the direction of the
fault.
As you move away from the transmitter, detector may stop indicating transmitter pulses. As
you near the fault, detector will resume indicating transmitter pulses. This is normal. Trans-
mitter pulses are strongest near the point of the fault (X) and at the transmitter ground.
When probes straddle the fault or transmitter ground, signal will drop.
• Function boxes
• Drop boxes
• Light poles
• Sunken ground
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