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Operating Principle
Manufacturers of safety cut-outs and breakers have different installation positions of the magnetic sensing
coil. If no clear signal can be pin-pointed, it is recommended that the receiver head is rotated by 90° either
left or right.
5.10 Locating of short-circuits in conductors (double-pole method)
When locating short-circuits in conductors, any existing circuits within the cable must be voltage-free.
Connect the transmitter as shown in Figure 10; and carry out this example as described in the application
example.
NOTE : The tracing depth for sheathed cable and conductors are different due to the fact that the
individual leads in the sheathed cable are twisted around themselves. Usually, short-circuits can
only be correctly detected when the short-circuit resistance is lower than 20 Ohm. The verification
of the short-circuit resistance can be carried out with any multimeter.
Figure 10:
Should the short-circuit resistance amount to more than 20 Ohm, it may still be possible to detect it using
the line interruption method. Different transmitter signals may also provide an accurate location.
NOTE : Switching sensitivity between Level 1 and Level 3 increases the sensitivity by a factor of 5.
Setup: manual mode, minimal sensitivity. Maximum tracing depth 0.5 m
5.11 Tracing installed water and heating pipes (single-pole method)
NOTE : The tracing conditions: The pipe to be located must be separated from the equipotential
bonding.
WARNING : For safety reasons the circuit must be switched off and isolated as per local
regulations.
Connect the transmitter “red” terminal to the pipe or conductor to be traced. The “black” terminal must be
connected to the Main Earth terminal. (Figure 11)
NOTE : Switching sensitivity between Level 1 and Level 3 increases the sensitivity by a factor of 5.
Setup: manual mode, minimal sensitivity. Maximum tracing depth 2.0 m.
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General