Wire quality identification

Cable

Wires and cables are essential materials for users in the process of power consumption. Their quality is directly related to the power safety of thousands of households. Therefore, when purchasing or selecting, how to quickly and accurately check the quality of wires (compensation wires, compensation cables, shielding compensation wires, shielding compensation cables, high temperature resistant compensation wires, high temperature resistant compensation cables, computer shielded cables, K-type compensation wires, S-type compensation wires and other wires and cables) is a skill that the majority of electricians must master.
When purchasing wires, you should buy them in regular shopping malls and recognize the national electrician certification mark (Great Wall pattern) and the trademark, specification, voltage, etc. printed on the wires.
One look and two try
Home decoration is inseparable from wires, especially old houses. Although wires are small, the "task" is great. Many fires are caused by aging wires, unreasonable configuration, or poor quality of wires. Therefore, when buying wires, consumers must polish their eyes, carefully identify and take precautions.
There are many varieties, specifications and prices of wires in the market, which makes it very difficult for consumers to choose. In terms of the price of 2.5 mm2 and 4 mm2 copper core wires commonly used in family decoration, the price of a coil of wires with the same specification can vary by 20% ~ 30% due to different manufacturers. As for the quality and length, it is difficult for consumers to judge whether they are good or bad.
According to insiders in the wire industry, the huge price difference of wires is due to the different raw materials used in the production process. The main raw materials for producing wires are electrolytic copper, insulating materials and sheath materials. In the raw material market, electrolytic copper is about 20000 yuan per ton, while the recovered miscellaneous copper is only about 15000 yuan per ton; The price of high-quality products of insulating materials and sheath materials is 8000 yuan ~ 8500 yuan per ton, while the price of defective products is only 4000 yuan ~ 5000 yuan per ton, which is even worse. In addition, insufficient length and insufficient glue content of insulator are also important reasons for the price difference. The length of each coil is 100 meters for high-quality products, while only 90 meters for defective products; The rubber content of insulators is excellent, accounting for 35% - 40%, while that of defective products is only 15%. Through comparison, it is not difficult for consumers to see that the difference in the sales price of finished wires is due to the fishy material.
So, how to identify the advantages and disadvantages when buying wires? I want to see. Check whether there is quality system certification; Check whether the certificate of conformity is standardized; Check whether there is factory name, address, inspection seal and production date; Check whether the trademark, specification, voltage, etc. are printed on the wire. It also depends on the cross section of the copper core of the wire. The superior red copper has bright color and soft color, otherwise it is a defective product. Second, try. A wire head can be bent repeatedly by hand. Those with soft hand feeling, good fatigue resistance, large elasticity of plastic or rubber hand feeling and no crack on the wire insulator are excellent products.