Kurth KE301 - Page 27

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The Probe is switched on by pressing and holding the LOW or HIGH key. To
ndasignalfromagreaterdistanceoraweaksignal,presstheHIGHkey.
In the case of large cable/line bundles at a distributor or in a platform, the
ProbeismovedatoverthebundlewhilepressingtheHIGHbuttonatthe
same time.
Once the cable/line with the strongest signal have been determined, press
theLOWkeytodenethecableyouarelookingforwithmillimeterprecision.
The highest signal level is always above the cable.
Searching Wire Pairs (Twin Wires)
When searching for twin wires and discovering overloads, an ET test lead
is connected to each core of a twin wire. In this case, it must be the twisted
pair. This can be done automatically by plugging into a junction box or by
connecting to the open cable end.
Using the Probe and holding the HIGH button down, the pair is found at
theotherendorateachdistributor.Tondtheexactpairwiththestrongest
signal, the LOW button is pressed. If the pair is twisted over the whole dis-
tance, then the exact pair is found. If, for example, there is a wire break or an
exchange of a single wire (split) on the route, several wires with the search
signal are found at the distributor. This then indicates a cabling error: Now
you have retrace back to narrow down the error.
For open cable ends, the procedure is similar. The wires are fanned out and
the Probe is moved evenly above them while pressing down the LOW button.
If the test tip of the Probe is now led over the wires, a high level is displayed
overtherstwireofthecorrectwirepair,aminimumlevelinthemiddle,and
ahighlevelagainoverthesecondwire.Thisidentiesthepairexactly.Ifno
minimum can be found, it is either the wrong pair of wires or there is a cable
fault, e.g. caused by an interruption, an exchange, or an overcurrent (what is
called a split pair).
The ET sends the search frequency with approx. 12 dB also into cables/lines
withaterminatingresistordownto50Ω.ThuswiththeET,asearchtonecan
also be sent to telephone or data lines carrying supply voltage. The maximum
cable/line/wire length is 15 km (unloaded).
2. Mode CONT – Continuity and Resistance Testing
If the slide switch on the right side of the ET set to CONT, the continuity test
mode is activated. A test voltage is applied to the test lead. This way, the
continuityofcables,lines,contacts,wires,orresistorsupto100kΩcanbe
tested easily.