Aerial bundled cables (also known as aerial cables or simply ABC) are overhead power transmission lines. It is usually tightly bundled with several insulated phase wires, and is usually used with bare neutral conductors.
For example, the commonly used three-layer service introduction cable is in contrast to the traditional practice of using non-insulated conductors separated by an air gap. This change in overhead power lines uses the same principles as bundle conductors, except that they are closer to the contact point, but each conductor is surrounded by an insulating layer (except the neutral wire).
The main objection of the traditional design is that multiple conductors are considered unsightly, and external forces (high wind conditions) will cause them to contact and short-circuit. The resulting sparks are one of the causes of forest fires in arid areas. In the UK, some supplies of rural property have been switched from TT grounding systems to PME / MEN. Some people worry that only low-level conductors may be damaged (eg, through high-altitude vehicles or fallen trees), but the upper phase conductors are intact. This is a potentially dangerous failure condition.
In a humid climate, tree growth is an important issue for overhead transmission lines. The aerial bundled cable will not arc when touched by a tree branch. Although continued friction is still a problem, pruning trees can reduce costs.
Low-voltage overhead cables have been developed in many countries around the world, and are becoming cheaper, safer, more reliable, require less tree cleaning and construction, more beautiful, less labor-intensive, require less maintenance and eliminate wires Jungle fire caused by collision.
Advantages our traditional overhead lines:
1. Be relatively immune to short circuits caused by external forces (high winds, fallen branches). Unless they scratch the insulation.
2. Can stand close to trees / buildings, and touch will not produce sparks.
3. There is almost no need to trim trees.
4. The installation is simpler and does not require cross bars and insulators.
5. Convenient installation and hanging line, low labor intensity, less construction resources required.
6. More aesthetics.
7. Significantly improved the safety of staff, especially working on live conductors.
8. Make stealing electricity more difficult.