A cable is a conductor that is covered with an insulating layer, a protective layer, a shielding layer, and the like for transmitting power or signal current and signal voltage. It can be divided into high voltage cable and low voltage cable according to voltage. Compared with low-voltage overhead lines and low-voltage overhead insulated lines, low-voltage cable lines are more costly and difficult to lay and maintain. Characteristics, and is widely used in low-voltage power distribution systems. It consists of three parts: wire core, insulation layer and protective layer.
The core is used to conduct current, and is generally made of stranded copper or aluminum strands. Low-voltage cables are single-core, double-core, triple-core, and quad-core. Two-core cables are used for single-phase lines, three-core and four-core cables are used for three-phase three-wire lines and three-phase four-wire lines, respectively. Single-core cables can be applied to single-phase lines or three-phase lines as required. Common low-voltage cable core cross-sections are 10, 16, 25, 35, 50, 70, 95, 120, 150, 185, 240 mm and so on.
The common laying methods for low-voltage cable lines are: ① directly buried; ② Lay in the cable trench; ③ Laying along the wall; ④ Lay inside a cable tunnel, etc. The type of low-voltage power cable is mainly selected according to the environmental conditions and laying methods used. Compared with low-voltage overhead lines and low-voltage overhead insulated lines, low-voltage cable lines are more costly and difficult to lay and maintain. Characteristics, and is widely used in low-voltage power distribution systems. Low-voltage cable lines are mainly used in places where high reliability of power supply is required, where corrosive gases and flammable, explosive, etc. should not be used to install low-voltage overhead lines or low-voltage overhead insulated lines.