The main types of products that are currently used for medium and low voltage cable accessories are heat shrinkable accessories, prefabricated accessories, and cold shrinkable accessories. They have the following characteristics: 1 Heat shrinkable accessories The material used is generally a blend of polyethylene, ethylene-vinyl acetate (EVA), and ethylene-propylene rubber. This kind of product mainly … Read more
Strengthen cable construction management. The following points should be done during cable construction: a. Strengthen the handover and acceptance. Before laying the cable, verify whether the type, specification, and quantity of the cable are consistent with the design drawings, and conduct insulation tests, and do not use unqualified cables; b. Strengthen the management of cable … Read more
Actively develop the ABC cable distribution network to meet the needs of load growth and urban construction (improvement of the city appearance and reduction of land occupation). In recent years, with the extensive use of cables in urban network construction and transformation, cable failures have gradually increased. It is an important task for electric power … Read more
The degree of crosslinking (hot extension) is unqualified If the degree of cross-linking does not meet the standard, the thermal-mechanical properties of the cable are unqualified and cannot meet the requirement of 90°C working temperature. The reasons for the unqualified cross-linking degree are the unqualified formula and the improper proportion of the compounding agent. The … Read more
The inspection of overheadcable is one of the basic contents of the operation and maintenance of overhead lines. Defects can be found in time through inspections so that preventive measures can be taken to ensure the safe operation of the line. Usually, line inspectors should do “nine inspections” when inspecting overhead lines. Check the pole … Read more
Commonly used plastics for wires and cables include polyethylene, cross-linked polyethylene, polyvinyl chloride, polypropylene, polyolefin, fluoroplastics, nylon, etc. Polyethylene is currently the most widely used and most used plastic. From the data in the table, it can be seen that polyethylene has low meson loss, high electrical resistivity, high breakdown field strength, good weather resistance, … Read more
The most direct cause of wire and cable aging failure is the breakdown of the insulation due to degradation. There are many factors that lead to the reduction of conductive insulation. According to actual operating experience, it can be summed up as the following situations. 1) Reasons for cable aging: external force damage. Judging from … Read more
What should a “smart cable” look like? Some experts gave an example of whether the wire and cable can understand the conveying capacity through the color of the surface, can have a temperature sensing function, and the color display can be different at different temperatures. For example, if the wire is transported more than 1000 … Read more
Power cable section The selection of power cable conductor cross-section should meet the following requirements: 1 The temperature of the cable bare conductor under the action of the maximum operating current shall not exceed the allowable value of the service life of the cable. Cable conductor work of continuous working loop The temperature should meet … Read more
1 The current and voltage of dual protection, as well as the two systems that need to enhance reliability, such as DC power supply and trip control loop, should use separate control cables. 2 In the following cases, the same control cable should not be used together: 1 Weak current signal, control circuit and strong … Read more