In modern society, the transmission of electricity and information is inseparable from the important tool of cable. In particular, high-voltage cables and low-voltage cables have significant differences in structure, application scenarios and voltage. In this article, we'll break down the differences between the two and show how they can be used with examples.
The structure of low-voltage cable is relatively simple, mainly composed of three layers: conductor, insulation layer and sheath. Conductors are the body of electrical energy transfer and are usually made of copper or aluminum, with a relatively small cross-sectional area. The insulation layer acts as an isolation between the conductor and the external environment, preventing current leakage and loss. The sheath protects the cable and enhances its resistance to abrasion and external environmental factors.
The structure of high-voltage cables is relatively complex, consisting of multiple layers such as conductors, insulation, shielding and sheaths. Conductors are also typically made of copper or aluminum, but are able to withstand higher voltages. The insulating layer acts similarly to a low-voltage cable, acting as an isolation and preventing current leakage. The shield is used to reduce electromagnetic interference and improve the signal transmission quality of the cable. The sheath protects the entire cable, enhancing its resistance to abrasion and external environmental factors.
In terms of voltage level, low-voltage cables are mainly used to transmit electrical energy below 1kV, and are suitable for electrical connection, indoor lighting and other fields. The rated voltage of high-voltage cable is greater than 35kv, which is mainly used for power transmission in the power grid.
In terms of production process, ordinary polyvinyl chloride and cross-linked polyethylene can be used in the manufacture of low-voltage cables. Medium and high voltage cables, on the other hand, can only be manufactured with cross-linked cables. In cables from 6 kV to 35 kV, three-layer co-extrusion and high-density cross-linked polyethylene production processes are often used. The thickness of the insulation layer of low-voltage cables and high-voltage cables is also different.
For example, a household wire is a typical low-voltage cable. It uses copper conductors, which have good electrical and thermal conductivity and are able to safely transmit low-voltage electrical energy. The insulation layer is made of polyvinyl chloride (PVC), XLPE and other materials to effectively isolate the conductor from the external environment and reduce the risk of current leakage. The sheath of household wires is generally made of PVC material, which has good wear resistance and fire resistance.
High-voltage cables, on the other hand, are mainly used in power transmission and industrial applications. For example, in transmission lines, high-voltage cables are able to withstand higher voltages and currents to ensure the stability of power transmission over long distances. In addition, in the industrial field, high-voltage cables are often used in scenarios such as motor drive, inverter control, etc., to support the operation of high-power equipment.
Through the above comparative analysis, we can see that there are indeed obvious differences between high-voltage cables and low-voltage cables in terms of voltage, structure and application. In practical applications, it is important to choose the right cable type to ensure the safety and reliability of power transmission and information transmission. At the same time, in the process of using cables, we should pay attention to safety issues, avoid circuit shorts and cable damage, and ensure the safety of people and property.