Operating instructions for Cable Detector, article 37270766
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5.2.3 Locating the cause of a short-circuit
Requirements:
The circuit must be voltage-free.
Connect the transmitter per Fig. 3-2-3.
The measurement procedure is the same as shown in the example.
1.
If the line is live, first turn the power off and make the circuit voltage-free.
2.
When searching for short-circuits in coated electric lines and cables, the search depth will vary as the
centre wires in the sheath are twisted around each other. Our experience has been that only short-
circuits with an impedance lower than 20 Ohms can be correctly detected. The impedance of the
short-circuit can be determined with a multimeter.
1.
If the impedance of the short-circuit is higher than 20 Ohms, try using the procedure for locating
interruptions in circuits to find the short-circuit. Use a relatively high current to connect the faulty
component (low Ohm connection) or interrupt it.
2.
When the signals to the receiver suddenly get weaker during testing along the line, the location of the
short-circuit has been found.
3.
Adjust the transmitter power to suit the different search radii.
4.
Set the receiver to manual mode and set the right sensitivity to precisely locate the circuit.