Device for locating defects in underwater telecommunication links

Apparatus for estimating locations of faults on a subsea telecommunications link, said link comprising a cable comprising at least one electrical conductor and including repeaters or regenerators subdividing said cable into sections, the apparatus comprising:

• two terminals, one for connection to said conductor and the other for connection to the sea or to ground;
• means, connected to said conductor, for automatically delivering regulated DC to said conductor with electrical power of at least 100 W;
• means, connected to said conductor, for absorbing an electrical power of at least 1 W which can be generated by the subsea link;
• one or more databases containing data concerning the resistances per unit length of the conductor of the cable sections, or concerning the voltage/current characteristics of repeaters or of regenerators;
• means, connected to said conductor, for automatically performing measurements, individually or in communication with another, identical apparatus, to determine a portion of the voltage/current characteristic at an end of the subsea link;
• and
• means, in communication with said means for performing measurements and said one or more databases, for automatically processing said portion of the voltage/current characteristic by making use of data from said one or more databases to estimate the location of the fault by said processing, free from falsification by the voltage/current characteristic of the fault.