Look at the qualified certification: no matter how bad the national standard line is, it is much better than the non-standard line. Look at whether there is a "CCC" and production license number of the national compulsory product certification, see whether there is a quality system certification, see whether the certificate is standardized, and see whether there are trademarks, specifications, voltages, etc. printed on the wire.
Look at the color of the copper core: peel off the insulation layer of a section of the wire, look at the color of the copper core conductor inside, the high-quality copper core wire is purple-red, called copper or red copper, the poor copper wire is golden yellow, called brass, and the worst copper wire is black, called iron copper.
Look at the insulating rubber: the insulation layer of the fake and shoddy wire looks very thick, but in fact most of them are made of recycled plastic, as long as you squeeze it a little harder, the extrusion will be white, and some powder will fall off. Scratch the insulation with your fingernails, if you can leave scratches, it proves that the insulation is less elastic.
Bending detection: take a section of wire, bend repeatedly in a certain place, high-quality wire can feel very soft in the bending process; if the insulation layer is white after bending, it proves that the insulation layer is too hard, too brittle, and it is easy to leak electricity after long-term use.
Combustion detection: burn the insulation layer with a lighter until the insulation layer catches fire, then take the lighter away, and calculate the extinguishing time of the insulation layer. Automatic extinguishing within 5 seconds, proving that the flame retardant performance of the insulation layer is up to standard; if the automatic extinguishing time is long, or even more and more vigorous, the flame retardancy is too poor, it is recommended not to buy.
