With the rapid development of the national economy and the continuous advancement of science and technology, power cables are now widely used in the construction of rural and urban networks. At present, in order to reduce the impact of cable construction workers on urban road traffic and improve the appearance of the city and the city, each city is actively improving its construction technology. In order to reduce the occurrence of cable faults, extend the service life of the cable and improve the reliability of the power supply system. This article mainly discusses wire and cable selection and laying installation technology. In the supply and distribution lines for civil buildings, the wires used are mainly wires and cables. The cable is a special kind of wire, which is composed of one or several insulated wires combined into a core, and a sealed packing layer on the outside, such as steel tape, rubber, and plastic, to protect it. In all kinds of electrical equipment, the conductors are the most used and most widely distributed in buildings. Selection of wire and cable models When using wire and cable, consider the use, laying conditions and safety conditions (1) Wire type wires are divided into bare wires and insulated wires. Bare wire models are JL (TJ) bare aluminum (copper) stranded wire, JL/G1A steel-cored aluminum stranded wire, etc., which are commonly used in overhead lines such as poles and towers. Insulated wire models include BVR, BLV, BVV, and BV. (2) Cable Types The cable types include VLV, VV, YJV, WDZA-YJY, and NH-VV. VLV (VV) type is PVC insulated, PVC sheathed aluminum (copper) core power cable, also known as plastic cable, commonly used in indoor distribution trunk lines. Selection of wire and cable cross-sectional area According to the environmental conditions of the wire and cable, after determining the type of the wire or cable, correct selection of the cross-sectional area of ​​the wire and cable is an indispensable and important condition for guaranteeing the safe and reliable use of electricity. The choice must take into account both safety and economics. How to choose the right wire and cable and laying installation technology Wire and Cable Consider mainly from three aspects: current carrying capacity, voltage loss conditions and mechanical strength (1) Current carrying method. The current-carrying capacity is the value of the current that is allowed to pass when the guideline or cable is continuously loaded for a long period of time. (2) Voltage loss conditions. The voltage loss refers to the loss on the line. The longer the line is, the greater the voltage drop will be and the load at the end of the line will not work properly. (3) Mechanical strength. Wires and cables should have sufficient mechanical strength to avoid breakage during wind, ice, or construction, resulting in power interruptions and other accidents. Cable laying method selection Cable laying methods should be based on local conditions, and should generally be determined based on site conditions such as the location of electrical equipment, outlets, groundwater level, and layout of process equipment. The main building is generally as follows. (1) All control cables leading to the central control room shall be laid overhead. (2) 6kV cables should be laid by tunnels or pipes, and the groundwater table can be overhead or laid with pipes. (3) For 380V cables, when the gap between the two ends of the equipment is zero meters, the tunnel, trench or platoon pipe should be laid; when one end equipment is on top and the other end equipment is down, some can be laid overhead; when the groundwater level is higher, Overhead cable. Power cable route path selection The power cable line should be based on the needs of power supply to ensure safe operation, easy maintenance, and take full account of the ground environment, soil data and underground road facilities, to save costs, facilitate construction and other comprehensive factors, to determine an economic and reasonable route direction . Specific requirements are as follows. (1) Save investment and try to choose the shortest path. (2) Select the cable path in combination with the long-range plan, and try to avoid the place where the plan needs to be constructed. (3) Cable paths Minimize the number of passes through various pipelines, railways, and other power cables. In buildings, the number of crossings of walls and building floors should be minimized. (4) In order to ensure that the safe operation of the cable is not affected by environmental factors, the cable must not be affected by external mechanical forces, chemical corrosion, vibration, and geothermal heat. (5) When one side of a road is provided with a drainage ditch, a gas pipe, a main water supply pipe, a weak current line, etc., the power cable should be laid on the other side of the road. After the cable path survey is determined, construction must be carried out with the consent of the local competent authority. Wire and Cable Cable laying requirements and exhibition methods (1) Directly laid cables should avoid the places where the upper level of the building needs to be excavated in the plan so that the cables will not be damaged or corroded. The buried cable must be armored and protected against corrosion. In flat design, choose short and straight paths as much as possible. (2) Manholes shall be provided when concrete pipes or pipes are used for laying. Manholes shall also be installed in branches, turnings, catchment wells and areas where the height difference is large. The distance between manholes is not more than 50m. Try to avoid and reduce the passage of underground pipes (including hot pipes, upper and lower water pipes, gas pipes), roads, railways, and communication cables. (3) The selection of cable laying methods should generally be considered from three aspects: saving investment, convenient construction and safe operation. The cable is directly buried and the construction workers are the most convenient, the construction cost is the lowest, and the heat dissipation is better. It should be preferred. (4) When determining cable structures, reserve brackets and holes should be reserved in conjunction with the expansion plan. Custom Cabinet CNC Router suitable for cutting on various flat materials, 2D engraving, 3D engraving. The size and function of the machine can be customized according to the requirements of the customer. 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Electrical Encyclopedia: How to Choose the Right Wire and Cable and Laying Installation Technology