Inductive Pipe and Cable Locators
Inductive locators are used to trace the path of conductive utilities, such as metallic pipes and cables.
They do not require a direct connection to the utility but rely on inducing signals onto the target utility.
Inductive locators do not require physical access to the utility to induce a signal. Instead, they generate an electromagnetic field that induces a signal in any conductive utility within range. This method is useful when direct connection to the utility is not possible or practical. Inductive locators can be used for a quick scan of an area to detect the presence of utilities, but they may not provide as precise as conductive methods.
In inductive mode, a transmitter is placed on the ground over the buried pipe or cable. If the transmitter is not within 1.5m/5ft of the line, the signal is likely to be very weak. The inductive method tends not to work where the utility is deeper then a few meters.
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A lab study of coupling effects of electromagnetic induction on underground utilities
Highlights
This paper is the first to evaluate such EM coupling effects amongst utilities.
Mapping subsurface utilities with mobile electromagnetic geophysical sensor arrays
Highlights
Remote sensing of buried utilities and explores its uses in today’s commercial devices and in research systems that may become commercially available in the next ten years.
Inductive Clamps
In inductive clamp mode, utility locating coupling clamps are used.
When the clamp’s jaws are closed around a pipe or cable, a signal can be induced into a particular line, reducing the chance of other conductors picking up signal.
The clamp must close fully, and the conductor must be well grounded on the near and as well as the far end.