Signal Generator:
Induction Multiple Services
It is important to check for the presence of adjacent services running close, or
parallel, to the conductor you have located.
1. Check that there are no accessories plugged into the connection socket.
2. Turn the Signal generator on and check that the batteries are OK.
3. Place the Signal generator on the ground ON ITS SIDE over the previously
located service so that you are no longer inducing a strong signal onto the service.
4. Re-scan the area looking for another peak close to where the original peak was
found. This operation should be repeated until you are satisfied that no further
services can be located.
NOTE This method can also be used to ‘mask’ one service so that another can be found.
NOTE The signal will be radiated up to 3 metres either side of the Signal generator but NOT directly below.
Limitations of Induction Method
- There are limitations concerning what can be achieved when using a Signal Generator
on the Induction mode compared to the Connected mode.
It is not normally possible to identify what the service is that has been detected with an induced signal. If the signal can
be followed far enough, a visible feature such as a valve cover or cable pit cover will be found that can indicate the
services identity.
Cables with a very small cross section may not have enough signal induced onto them to make them detectable. It is
often not possible to apply an induced signal onto just ONE specific buried service, in order to trace that service alone,
when that service is positioned close to other services.
NOTE An induced signal cannot be applied to a buried service that lies beneath reinforced concrete. The reinforcing
bars will re-radiate the induced signal masking any signal that has been induced onto the buried service below.
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