[up knowledge] how to distinguish between true and false national standard cable
It’s true that it’s true and false, and it’s true and false. Nowadays, the non-standard and national standard wire and cable on the market is really dazzling. Some of the products produced by non-standard lines are even more professional than the national standard. It is really difficult to distinguish between true and false, so how to distinguish the true and false national standard line. The following six methods are recommended:
1. See product line certification
Look at the quality system certification; see if the certificate is standardized; see if there is a factory name, site, inspection chapter, production date; see if the trademark is printed on the wire, specifications, voltage, etc. A series of certificates from regular manufacturers are available. If there is no detailed quality certification certificate, the procurement company may have to examine it carefully.
2. Weighing, length
Good quality wires 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 1.5mm2 is 1.8-1.9kg per 100m; the plastic insulated single-strand copper core wire of 2.5mm2 is 3~3.1kg per 100m; the plastic of 4.0mm2 Insulated single-strand copper core wire is 4.4 to 4.6 kg per 100 m weight. Is the poor quality wire underweight? Or is it not long enough? Or the wire has too much copper core impurities. There is also the length, the country is not forced to play rice, but there are many manufacturers also played rice, playing rice is not necessarily the national standard, but the general national standard generally does not play rice. Non-standard rice is only a means, the general national standard line length is 100 meters. You should also measure the wire diameter with a micrometer. Now the minimum wire size in the house is 2.5 square meters. 1.5 is no longer played. Today's businesses often cut corners, BV2.5 square single-strand plastic copper wire core diameter should be 1.78mm, outer diameter (including leather) 3.9mm. BV4 square single-strand plastic copper wire core diameter should be 2.25mm, outer diameter (including leather) 4.4mm.
3. Look at copper
The higher the brightness of copper, the better the copper, and the smoothness, luster, and no layering. The qualified copper core copper core should be purple, shiny and soft. If you can cut off a small piece of plastic skin, look carefully at the copper wire inside, touch the top of the copper wire with your palm, feel flat and tingling, feel softer, and the copper core of the inferior copper core is purple black. , yellowish or white, with many impurities, poor mechanical strength, poor toughness, will break when used a little, and there are often broken wires in the wire. When inspecting, you only need to peel the wire 2CM at one end, then use a piece of white paper to rub it slightly on the copper core. If there is black substance on the white paper, it means that there are more impurities in the copper core. In addition, the inferior wire insulation layer seems to be very thick, and in fact it is mostly made of recycled plastic. Over time, the insulation layer will age and leak.
4. Test feeling
It is advisable to repeatedly bend a wire head by hand. Anyone who has soft hand feeling, good fatigue resistance, strong plastic or rubber feel and no crack on the wire insulation is a superior product. At the same time, because the cost of counterfeit and shoddy wires is low, so there will be differences in the feel. It is often sold at a low price and cheap, making it difficult to distinguish the authenticity.
5. Inspection sheath
The insulation layer of counterfeit products seems to be very thick? But in fact, most of them are made of recycled materials. The product has poor toughness, poor resistance to damage, and easy to peel off cracks. Especially in the process of home decoration, it is very easy to wear. There is a huge safety hazard. . As long as the general insulation sheath has no metal impurities in the material, it can pass through the high-pressure test. However, the average consumer can distinguish the quality of the jacket by a simple stretching method. The insulating sheath of the return material is mostly doped with calcium carbonate, which may appear white and easily break during the stretching process.
6. Burn with fire.
Inferior wires and cables will burn quickly with fire, and there will be an open flame and smoke. Good quality cables burn slowly, have a small amount of smoke or smoke, and have no open flame.
