Method of distinguishing the quality of wire and cable
In recent years, the news of counterfeit and shoddy cable products has emerged in an endless stream. Many unscrupulous manufacturers in the cable industry have sacrificed product quality for the pursuit of interests, making the cable market a must-have. As for the quality of the quality, the length is up to standard, consumers are more difficult to determine. In the past 3.15, some unqualified cable products were ruthlessly exposed, which also sounded the alarm for the cable industry - quality and efficiency, a long way to go.
1. Recognize the certificate identification
When purchasing, be sure to check whether there is a “3C” certification mark on the certificate. The model specifications, rated voltage, length, date of manufacture, certification number, inspection, execution standard, factory name, and factory address are clear.
2. Pay attention to the packaging
When purchasing, pay attention to the packaging, the printing should be clear, the model specifications, factory name, and factory address are complete. Counterfeit and shoddy wires and cables are often "three no products", but there are also ambiguous origins and other signs, such as manufacturing in China, manufacturing in a certain province of China or a certain city, which is actually equal to the unmarked place of origin.
3. View the appearance
When purchasing, pay attention to the appearance of the film to be smooth and round, uniform in color and good in feel. In the case of rubber wire and cable,the sheath and insulation can be burned with a cigarette but the surface is completely free of damage.
4. Check the conductor
The conductor should have a certain luster and moderate softness, and the conductor size should meet the requirements of national standards. The cross section of the copper wire of the wire and cable, the superior product copper color is bright and the color is soft, otherwise it is a defective product.
5. Check the length
When purchasing weak electric cables, don't try to buy cheap cables. If you buy only 90m or 80m, or even the length and length of the wire and cable, the length must meet the standard requirements of 100 (+/-) 0.5m.
6. Look at the PVC sheath
The surface can be seen to have a regular "unevenness" in the inner mesh, which indicates that the processing technology is good and does not produce relative sliding. It is a good cable. The appearance is smooth, and the "unevenness" of the compacted net is not seen. The hand-pinched jacket has a loose feeling, which is a poor cable;
7. Check the shield layer network
Whether the number is enough for copper meshing, check for solderability, tinned copper wire scrape to see if it is copper wire,the hardness of aluminum-magnesium alloy wire is obviously larger than copper wire; the mesh is sparse, the distribution is uneven, and the insulation layer is not wrapped. Tight is the difference cable;
8. Check the core
Diameter - SYV cable is 0.78-0.8mm, SYWV cable is 1.0mm; recently there is a SYV75-5 core wire diameter of 1.0mm cable, the characteristic impedance of this cable is certainly not 75 ohm, not applied to 75 In an ohmic transmission system.