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3 Using the vLoc3 RTK-Pro
3.3.2 Signal Clamp (for frequencies above 8kHz)
In many situations, it is not possible to gain access to a cable to make an electrical contact. Or if there is, it is not safe to do so.
The signal clamp provides an efficient and safe method of applying a locate signal to a cable.
Note that for the best results, the cable should be grounded at both ends. The clamp should be fully closed for optimal current
induction. A small amount of current will still be induced if the jaws are open.
When clamping around a cable, make sure the clamp is placed below the grounding point, as shown below.
When applying a clamp close to a grounding point where multiple grounds or a grounding bus exists, ensure that you place the
clamp around the target line and not to the ground bus or other grounds. This will help focus the applied signal to the target line.
Clamp Extension Rod
A useful accessory to the clamp is the extension rod:
The extension rod is fitted with a 10mm threaded male stud. This male thread screws into the handle of the signal clamp to
extend the distance of the clamp. This is helpful in areas with difficult access, such as in manholes or overhead cables (not to be
used on uninsulated overhead power cables).
The extension rod is also fitted with a female thread in the handle, which enables the rods to be fitted together to further extend
the range. To access this thread, slide the yellow handle off the rod.
To operate the clamp jaws when attached to the rod, gently pull on the clamp cord, which will open the jaws. Release cable to
close them.
