Operation - Textron GREENLEE 521A Instruction Manual

Operation

Locating Wire Path
With the probe pointed toward the ground, walk completely around the transmitter
location. An absence of tone or null will be detected directly over the path of the
wire. Movement to either side will cause the volume of tone signal intensity to
increase. Follow the null to determine the wire path. (Refer to Figure 2.)
Finding Wire Breaks and Nicks
When attempting to find breaks and nicks, you should decrease the sensitivity of
the receiver when pointing it off to either side of the null. You will be able to notice
the change in signal intensity immediately. Do not allow the meter to peg or go
above 10. This will greatly help in the fault locating process.
Note: The wire must have a path to ground to be successfully located. These
paths exist in a great majority of all direct buried wires due to insulation
imperfections, nicks, and bad splices. If not, create one by grounding the
remote end.
• The end of a cut or broken wire can be located by following the path until the
null disappears and gives way to a hot spot. Beyond the hot spot, no null can be
detected. Back up until the null is detected, and this will be the approximate end
of the broken wire. (Refer to Figure 3.)
Tone
Null
Wire
Figure 2 – Locating Wire Path
7
Receiver
Tone
Signal
Intensity
521A