1. At present, there are many types of wires and cables on the market, with many specifications and chaotic prices, making it very difficult for consumers to choose. In general home decoration, two types of copper core wires, 2.5 square millimeters and 4 square millimeters, are commonly used. However, in terms of price, the price of a coil of wire with the same specifications can vary by 20 to 30 yuan due to different manufacturers. As for the quality and whether the length meets the standard, it is even more difficult for consumers to judge. According to industry insiders, the huge price difference in wires and cables is due to the different raw materials used in the production process. The main raw materials for the production of wires and cables are electrolytic copper, insulation materials and sheathing materials. At present, electrolytic copper in the raw material market costs more than 70,000 yuan per ton, while recycled miscellaneous copper is much cheaper; the price difference between high-quality products and defective products of insulation materials and sheathing materials is even greater. In addition, insufficient length and insufficient glue content in the insulator are also important reasons for the price difference. The length of each coil of wire is 100 meters for high-quality products, but only about 90 meters for defective products. The glue content of the insulator accounts for 35 to 40 meters for high-quality products, while only 15 for defective products. Through comparison, it is not difficult for consumers to see that the difference in sales price of finished wires and cables is caused by the flaws in the materials. So, how to identify the pros and cons when buying wires and cables?
One thing to look at: see if there is a quality system certification; see if the certificate is standardized; see if there is a factory name, address, inspection seal, production date; see if there are trademarks, specifications, etc. printed on the wires and cables. voltage etc. It also depends on the cross-section of the copper core of the wire and cable. The high-quality copper is bright and soft in color, otherwise it is a defective product.
Two things to try: You can take a wire and cable head and bend it repeatedly by hand. Any product that feels soft, has good fatigue resistance, has high elasticity in the plastic or rubber feel and has no cracks in the wire and cable insulator is a high-quality product. Wires and cables are indispensable materials for users in the process of using electricity. Their quality is directly related to the electricity safety of thousands of households. Therefore, when purchasing or selecting, how to quickly and accurately check the quality of wires and cables is a skill that the majority of electricians must master.
2. 1. Weight: Good quality wires and cables are generally within the specified weight range. For example, the commonly used plastic insulated single-strand copper core wire with a cross-sectional area of ??1.5 mm2 weighs 1.8 to 1.9 kg per 100 m; the plastic insulated single-strand copper core wire with a cross-sectional area of ??2.5 mm2 weighs per 100 m. 2.8 to 3.0 kg; 4.0 mm2 plastic insulated single-strand copper core wire weighs 4.1 to 4.2 kg per 100 m, etc. Poor quality wires and cables have insufficient weight, insufficient length, or too many copper core impurities in the wires and cables.
2 Copper quality: The copper core of qualified copper core wires and cables should be purple-red, shiny, and soft to the touch. The copper core of fake and inferior copper core wires is purple-black, yellowish or white, with many impurities, poor mechanical strength, and poor toughness. It will break with a little force, and there are often disconnections in wires and cables. When checking, you only need to peel off 2 cm of one end of the wire and cable, and then rub the copper core with a piece of white paper. If there is black substance on the white paper, it means there are more impurities in the copper core. In addition, the insulation layer of fake and inferior wires and cables seems to be very thick, but in fact most of them are made of recycled plastic. Products produced from this material have poor toughness, poor damage resistance, and are easy to peel and crack. Over time, the insulation layer will age and deteriorate. Electricity leakage may cause safety accidents.
3 Manufacturers: Counterfeit and shoddy wires and cables are often "three-no products", but they also have ambiguous origin and other markings on them, such as Made in China, Made in a certain province or city in China, etc. This is actually equivalent to unlabeled products. Origin.
4 Price: Due to the low production cost of counterfeit and inferior wires and cables, vendors often sell them at low prices under the guise of low price and high quality, which deceives people.