How to Deal with Moisture in Electrical Power Cables

In urban power grid reconstruction projects, electrical power cables have been widely used. However, due to the particularity of the cable, there are special requirements for the installation, operation and maintenance of the cable. Moisture or water ingress of the cable reduces the insulation resistance of the cable, which is an important aspect of the operation accident of the cable line.

Ⅰ. Reasons and hazards of electrical power cables getting wet and entering water

1. When the new cable leaves the factory, both ends are sealed with plastic sealing sleeves, but after a section is used according to the actual situation at the construction site, the remaining part is simply wrapped with plastic cloth. If it is not placed and sealed well, over time, water vapor will inevitably seep into the cable.

2. When laying electrical power cables, it is necessary to often cross roads, bridges and culverts. Due to weather or other reasons, a lot of water often accumulates in the cable trench. During the laying process, it is inevitable that the cable head will be immersed in water. .

3. After the laying of the electrical power cable is completed, the cable head cannot be made in time due to the limitations of the site construction conditions, so that the unsealed cable fracture is exposed to the air for a long time, or even immersed in water, so that a large amount of water vapor enters the cable.

4. In the process of making the cable end, due to human negligence, moisture may penetrate into the process of handling the cable end.

5. During the normal operation of the cable, if there is a breakdown such as breakdown for some reason, the accumulated water in the cable trench will enter the cable along the fault point, and the cable insulation will be seriously damaged, which will also cause the cable to enter the water.

Ⅱ. What should I do when the electrical power cable enters the water and gets damp?

1. After the cable is laid, make the cable head in time, and complete the wiring to eliminate hidden dangers in the bud.

2. If only two ends of the cable enter the water, it is only necessary to cut off the two ends and reconnect the cable ends.

3. If the cable has an obvious water inlet point, it is necessary to cut off the cable near the water inlet point and make an intermediate joint.

4. There is inevitable water accumulation in outdoor cable wells or cable passages. Try to fix the cables with brackets as high as possible.

5. Use special hot nitrogen to pressurize and dry the cable inside. Generally, there is no such professional equipment.

6. Regularly conduct pressure and leakage tests on the cables to ensure timely understanding of the running status of the cables.

The best solution to avoid water ingress of electrical power cables is prevention. Once the cable is seriously damped, it is basically scrapped, so we can choose high-quality cables to reduce the risk of dampness in the early stage. In addition to the selection of high-quality cables, daily inspection and maintenance are also very important. After all, various hidden troubles have been eliminated, so that the electrical power cables can be used normally and will not cause more serious accidents. Only in this way can the safety of the power distribution network be guaranteed. Stable operation.