1. Look at the packaging. Drum packaging can reduce the insulation layer wear caused in the production, shipping and handling process, and convenient for electrician installation. There should be complete certificate in the packaging, the certificate should include specifications, implementation of scale, rated voltage, length, date, name and address and other complete information.
2. Look at insulating rubber. Shoddy wire insulation looks like very thick, in fact most of them are made of recycled plastic, squeeze just a little harder, the white-like powder will fall at the place being squeezed.
3. The weight of the wire. Good quality wire from professional usb cable manufacturer is generally designated within weight range. Like the common cross-sectional area of 1.5mm2 plastic insulated single strand copper wire, the weight is 1.8 ~ 1.9kg per 100m.
4. To see the color of the copper. The copper core of qualified copper wire should be purple, shiny, soft feel, while the copper core of shoddy copper wire is purple black, yellowish or whitish.
5. Have a look at the length and the line core thickness. The relevant scale designates that the tire length error cannot be more than 2%, cross-sectional diameter must not exceed 0.02%, but there is a large number in loss in the length and fraud in cross section on the market (line section marked as 2.5 mm2, but is only 2 mm2 thick in reality) phenomenon.
6. Intercept an insulating layer, and look whether line core is located in the middle of the insulating layer. Not centered is the eccentric phenomenon caused by the not high technology, it can remain silent when use small power and once the consumes quantities are huge, the thinner side is likely to be breakdown by the current.
7. Get a wire head to repeatedly bend by hand, if it is soft, good anti-fatigue strength, plastic or rubber feel elastic and no cracking on wire insulation, it is superior product. Wire outer plastic skin should glory bright, fine texture, no flame when being ignited with a lighter.
8. First see whether there is the Chinese national compulsory product certification "CCC" and production license number on the volume of wire packaging sign; see whether there is quality system certification; see whether the certificate is qualified; see whether there is the plant name, address, overhaul chapter, production date.
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