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The principle of overhead cable fault indicator

2022-09-27 15:23:47 admin

1. Principle: The fault indicator is an electromagnetic induction device that can reflect the passing of short-circuit current and the fault sign (red card). The fault indicator is installed along the distribution line. Once the line fails, the short-circuit current flows, the fault indicator will act, and the fault sign red card will appear. Then patrol along the line, the fault indicators from the power supply side to the fault point all show red cards, and the fault indicators after the fault point do not show red cards, so it can be judged that the fault point is between the last red card point and the first non-red card point.

2. The fault indicator usually includes current and voltage detection, fault identification, fault indicator drive, fault status indication and signal output and automatic delay reset control.

3. The fault indicator is generally installed on overhead lines, overhead cables or buried cables, and switch cabinet busbars. Therefore, it detects the voltage by detecting the potential gradient of the space electric field, and detects the line current by electromagnetic induction.

4. The fault indicator refers to a device installed on the power line (overhead line, cable and busbar) to indicate the fault current. Most fault indicators can only identify and indicate short-circuit faults by detecting the characteristics of short-circuit current.


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