Cable Identifier is a special instrument used to identify a particular cable from a bunch of cables in the erection, migration and maintenance of power cables and fault treatment. The cable identification instrument is composed of signal generator, clamp signal detector and indicator. The signal generator mainly produces special pulse modulation signal. The output line is added to the cable under test when it stops running. The cable under test is searched in the field by the receiving clamp. When the receiving clamp detector detects the special signal applied on the cable, the meter pointer on the signal detector and the communication are applied. No.1 Frequency oscillates synchronously, while the signals detected on other cable lines are much smaller and in opposite directions. It is easy to determine the measured cable by indicating the magnitude and direction by the meter.

According to the conditions of use, the searching methods of cable identification instrument can be divided into live cable identification instrument and non-live cable identification instrument. Their respective searching methods are pointed out below.

1. Search method of live cable identifier

When the line is live, we can't affect the normal operation. When identifying the cable with a point, we use induction method to measure it. The high frequency signal is transmitted by the caliper. After receiving the signal characteristics, the receiver filters the software and hardware to identify the phase. When the receiving caliper is in accordance with the current direction card cable, the identified cable ammeter deviates to the right, accompanied by acousto-optic indication. The current direction of other cables is opposite to that of the identified cables, and the ammeter pointer is left-sided. There is no sound and light indication. This reflects the uniqueness of the identified target cable. It is easy to distinguish the identified cables from multiple cables.