Glomar C.A.T4 Handbuch Seite 4

loCaTI N G s Mall d IaM eTe r CaB le s
C.A.T4 and Genny4 have been designed to increase the likelihood of
detecting smaller cables such as telephone lines or CATV, particularly
service drops from the road or pathway to a property. The Small
Diameter Locate frequency transmitted from the Genny4 is designed
to 'jump' onto these cables using one of three methods:
signal jumping through external insulation /coatings
With the Genny4 switched off, plug the direct connection leads into
the Genny4 and connect the black lead to the earth stake or suitable
ground point. Clip the red lead directly onto the cable insulation to
allow the Small Diameter Locate signal to jump onto the metallic wires
inside. If clipping on is not possible, place the red clip as near to the
cable as possible, which may include clipping to the protective cover
of the service. Alternatively, run the red lead around a non-metallic
casing or conduit containing the target utilities, and clip it to itself to
achieve this effect.
Switch on the Genny4 and set the C.A.T4 to Genny mode to locate
the buried cable. Note that the signal boost function will not have a
significant effect in this mode.
signal jumping from an accessible cable
If a small diameter cable runs close to, or parallel to, a more
accessible cable – e.g. a street lighting cable, the Small Diameter
Locate signal may be able to jump from one cable to another. Use the
Direct Connection or Signal Clamping methods as described below to
transmit both signals to the accessible cable. When scanning an area
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for underground utilities, the jumping Small Diameter Locate frequency
can be differentiated from the standard Genny signal by a different
audio tone.
d I r e CT CoN N e CTI oN
Connection to a power cable sheath should only be
undertaken by qualified personnel.
Direct Connection is an effective way to apply the Genny4 locate
signal to a specific cable or pipe network so that it can be traced
from above ground. Connections can be made to any metallic part of
the pipe or cable such as valves, meters, junction boxes, street lights,
pipeline markers or other access points.
With the Genny4 switched off, plug the Direct Connect lead into
the accessory socket. Attach the red lead to the pipe or cable
(if necessary, clean the connection point to ensure a good electrical
contact). If the jaws of the clip do not open far enough, and if the
connection point is a suitable material, use the supplied magnet.
Connect the black lead to the earth stake which should be secured in
the ground 3 – 4m away from, and at right angles to the target line.
Alternatively the black lead may be clipped to a valve box, manhole
cover or another earthed point. Use the earth spool lead to extend the
earth connection if necessary.
Switch the Genny4 on. A good connection is indicated by a drop
in loudspeaker tone. If there is no tone, or if the power boost LED
flashes, replace the
batteries.
Use the C.A.T4 to
scan the area for
the target pipes or
cables (see 'Locating
with C.A.T4').
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