Direct Connection; Induction Mode - Radiodetection SuperCAT 4+ User Manual

Cable location using the
T1 transmitter
The T1 transmitter is used to actively apply a locate signal to cables
or metallic pipes. This signal can be traced using the locator in Active
Line mode (L).
Use of the T1 is strongly recommended, as passive, power or radio
signals may not be present, or detectable, on all cables and pipes.

Induction mode

The T1 has an internal aerial that will induce a signal onto a line (or lines)
directly below it. This is useful when you do not have direct access to
the line. Generally, induction is only effective to depths of 2m (6'6").
Note that the induction mode is indiscriminate and will apply a signal to
all conductors within its range.
Induction is only available with frequencies 8kHz and above.
Procedure
Place the transmitter over the approximate position of the underground
utility with arrows pointing parallel to its path. Set the locator's sensitivity
to 100% and start locating the line at least 10m (33 feet) away from the
transmitter. Mark the ground when the locator detects any signal spike.
Note: Induction cannot apply a signal to a line below reinforced
concrete.
Note: The locator may detect the transmitter signal directly
from the T1 rather than the target line, so do not attempt depth
measurements within 10 meters of the transmitter.
To check if you are detecting a signal from the T1, point the locator directly
at the transmitter. If the locator's signal strength increases, either reduce the
transmitter power or increase the distance between you and the transmitter.
If the signal strength decreases, the signal is from the buried line.
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Direct connection

Connection to a power cable sheath should only be
undertaken by qualified personnel.
Direct Connection is an effective way to apply the T1 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.
Procedure
With the T1 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 T1 on. A good connection is indicated by a drop in
loudspeaker tone. If there is no tone replace the batteries.
Start with the T1's lowest power setting. A pulsed loudspeaker tone
indicates a good connection. If there is no tonal change, check the
electrical contacts and the ground. If necessary, change the position of
the ground stake or pour water over the ground contact if placed in dry
soil or sand. If there is still no change in tone increase the power setting.
Note: The locator can detect a signal many times weaker than
what is necessary for a T1 tone change and short distances can
be traced without a pulsed tone from the loudspeaker.
To remove the direct connection cable grip the black sleeve on the
outside of the plug and ease off the connector.
Do not pull the wire as this may damage the cable and/or
socket.
Regularly check your locator and T1, in all modes over a cable which
provides a response that you are familiar with.
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