Precise locating of line interruptions using two transmitters
Example 8 (single-pole application)
NOTE:
By touching the contact electrode „7" the sensitivity range is increased to factor 1.5.
When locating a line interruption using one transmitter to feed from one conductor end,
the location of interruptions may not be precisely located in case of bad conditions due to a
field disturbance. Furthermore, when feeding with only one transmitter, special case has to
be taken that the transition resistance of the interruption is higher than 100kOhm.
The drawbacks described above can easily be avoided when using two transmitters (one from
each end) for line interruption detection. In this instance, each of the transmitters are set to
a different line code (e.g. transmitter one to code „F", the other transmitter to code „C"). A
second transmitter with a different line code is not included within the scope of supply and,
therefore, has to be ordered separately.
The transition resistance of the line interruption has to be higher than 10 kOhm for this
application.
If the transmitters are connected in accordance with the figure shown below, the receiver
indicates „E" at the left side of the line interruption. If you continue further than the
interruption, towards the right, the receiver displays „F". If you are directly above the
interruption, no line code is displayed, due to the overlapping of both transmitter signals. The
line interruption is located exactly in the middle between the displayed line codes „E" and
„F".
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