The specialty of Overhead power line and Insulated electric cable
1. Overhead line: The cable is a non-insulated bare metal conductor. In the aerial, the insulator string is fixed in the tower, and the air is insulated. The main advantage: low cost. Its disadvantage is that it uses more land resources (line corridors), which affects the appearance of the city.
2. Electrical insulated cable: Use metal conductor insulated from the outside world. They are laying the ground or underground. Its main advantage is that it is more convenient to lay, occupy less land resources, and does not affect the appearance of the city. The disadvantage is that the cost is too high.
At present, it is considered to be safe, due to the material and manufacturing process…the safety of overhead cables is better than that of power insulated cables, and the failure rate is much lower than that of power cables. In addition, there is also a “pipeline insulation car”, which is filled with gas (or other) as an insulating medium in conductors and metal shells. Higher cost.