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What are the differences between power cables and control cables?


Power cables are cable products used to transmit and distribute high-power electrical energy in the main line of the power system, including high-voltage cables with various voltage levels and various insulations of 1-500 kV and above. High-voltage cables are cables used to transmit and distribute electrical energy, and are often used in urban underground power grids, the emergence of power stations, internal power supply in industrial and mining enterprises, and underwater transmission lines across rivers and oceans.

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Power cables are cable products used to transmit and distribute high-power electrical energy in the main line of the power system, including high-voltage cables with various voltage levels and various insulations of 1-500 kV and above. High-voltage cables are cables used to transmit and distribute electrical energy, and are often used in urban underground power grids, the emergence of power stations, internal power supply in industrial and mining enterprises, and underwater transmission lines across rivers and oceans. 
 

Basic structure of high voltage power cable

The basic structure consists of four parts: core conductor, insulating layer, shielding layer and protective layer. The core core is the conductive part of the power cable, which is used to transmit electrical energy and is the main part of the power cable. The insulating layer is an indispensable part of the power cable structure, which directly separates the conductor from the ground and conductors of different phases to ensure the transmission of electrical energy. The shielding layer of 15KV and above generally has a conductor shielding layer and an insulating shielding layer. The function of the protective layer is to protect the power cable from external impurities and moisture, and prevent external forces from directly damaging the power cable.
Main advantages of high voltage power cables
1. It occupies less land area, and is generally buried in the soil or laid indoors, in a ditch, or in a tunnel. The insulation distance between the lines is small, no tower poles are required, the floor space is small, and the floor space is basically not occupied.

2. High reliability, less affected by climatic conditions and surrounding environment, stable transmission performance and high reliability.

3. The distributed capacitance is large.

4. The maintenance workload is reduced.

5. The possibility of electric shock is small.

                                                
The difference between power cable and control cable

Power cables are used to transmit and distribute large-scale electrical energy in the mains of the power system. Control cables directly transmit electrical energy from the distribution point of the power system to the power supply connection lines of various electrical equipment and appliances.

1. Differences in function: Control cables directly transmit electrical energy from the distribution points of the power system to the power supply connection lines of various electrical equipment and appliances, while power cables are mainly used in power generation, distribution, transmission, transformation, and power supply lines. Electric energy transmission, the passing current is large, and the power cable is used to transmit and distribute large-scale electric energy in the main line of the power system.

2. The difference between the implementation standards: the control cable standard is 9330, the power cable standard is GB12706,

3. The difference of the core color: the color of the insulated core of the control cable is generally black and white, and the low voltage of the power cable is generally color-separated.

4. The difference in cross-section: the power cable is a primary load wire, the current carrying capacity increases with the increase of power, and the application cross-section of the wire must also increase with the increase of the current, so the specifications of the power cable are generally larger, as large as 500 square meters (the range that conventional manufacturers can produce), no matter how large the cross-section can be, there are relatively few manufacturers that can do it, and the control cable is a secondary command wire, which controls the current-carrying operation of devices such as contactors, and the load current is extremely small. , the wire cross-section is extremely small, so the cross-section of the control cable is generally small, and the maximum is generally not more than 10 square meters.

5. The difference of rated voltage: the rated voltage of the power cable is generally 0.6/1kV and above, and the control cable is mainly 450/750V.

6. The difference between the wire sheath: the power cable requires the wire sheath to have sufficient compressive strength, tensile strength, temperature resistance and corrosion resistance. Control cable requirements are relatively low. When the industrial electrical power cables and control cables of the same specification are produced, the insulation and sheath thickness of the power cables are thicker than those of the control cables.

7. The difference in the number of cable cores: the number of power cable cores is small, there are single core, two cores, 3 cores, 4 cores (three-phase four-wire system), 5 cores (three-phase five-wire system), according to the requirements of the power grid, Usually up to 5 cores. The control cable is used to transmit control signals, and the number of cores is large, ranging from 2 cores to 61 cores, or even more. The control cable also adopts various core structures, shielding and other measures to obtain satisfactory electromagnetic compatibility effects.