Radiodetection rd7000+, Руководство по эксплуатации

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The user in the boat should be a specialist or have
considerable experience using a locator so that they
can give concise instructions to the diver.
It is prudent for the pair to practice working together on
dry land before attempting to locate underwater. Using
the antenna the diver should locate and trace a known
line blindfolded receiving directions from the user with
the locator out of sight of the line and the diver.
Because of rapid signal loss and a combination of large
surface area and very conductive soil there may be
problems applying a suitable signal for tracing a large
diameter pipe. It may be necessary to use a high power,
low frequency tracing signal.
It is necessary to define a method of recording target
line position and depth before starting work in the boat
or on the seabed.
Figure 8.11: Using a submersible antenna
WARNING: The operator using the submersible
antenna must be a properly licensed and experienced
diver.
Section 9 - Fault-Finding
9.1 About fault-finding
The PLM and TLM are capable of locating
cable to ground faults caused by damaged cable
sheaths and can also be used to locate damage to
insulation on pipelines. This process is known as Fault-
Finding and uses specific fault find signals applied to
the target.
Fault find signals can only be applied using direct
connection method.
The accessory A-frame is used to locate cable sheath
faults on power and telecom cables or insulation faults
on pipelines. To use Fault-Find you will need the
following equipment:

locator

Tx-5 or Tx-10 transmitter

Accessory A-frame with connecting lead

Direct connection lead and earth stake
9.2 Preparation
Using standard locating techniques locate the
cable or pipe for a short distance and trace and mark its
route. Remove all earth bonds from the line to be traced
during the fault-finding survey. If there are any earth
bonds along the path the fault find signal may direct the
user to this location as this will be the preferred path for
the fault find signal to leak away into the ground and
may result in the fault not being located.