As a part of power lines, power cables are widely used because of their low probability of failure, safety and reliability, and flexible outlets. However, once a fault occurs, the maintenance is more difficult, so special attention should be paid to the maintenance and testing.

1. Preparation before work

One type of work ticket should be used for power outage work, and the second type of work ticket should be used for work that does not require power outage. Before work, you should check the relevant path diagrams, arrangement diagrams, and the drawings and materials of the concealed project in detail. You must check the cable name and whether the identification plate is consistent with the work ticket. Work can only be started after the safety measures are correct and reliable.

2. Matters needing attention at work

The cables to be repaired must be confirmed when working. The cables to be overhauled can be divided into two types:

(1) Cables with terminal head failure and obvious failure points on the surface of the cable body. This kind of cable failure has obvious signs of failure and is easy to confirm.

(2) The cable surface does not expose the cable of the fault point. For this type of faulty cable, in addition to checking the data and verifying the cable name, it must also be identified with a cable identifier to distinguish it from other live cables in operation, especially when there are many cables in the same section. It is particularly important to distinguish the cables that need to be overhauled from other live cables. At the same time, this can also effectively prevent the misidentification of the cable due to the wrong cable tag, which leads to accidental disconnection of the live cable.

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