The national standard wire rod is completely produced according to the national standard. General household and common wires meet the standard specifications, and the national standard stipulates five common specifications. See if there is a quality system certificate; See if the certificate is standardized; See if there is a factory name, address, inspection stamp and production date; See if there are any trademarks, specifications, voltages, etc. Printed on the wire.
It also depends on the cross section of the copper core of the wire. Superior copper is bright and soft, otherwise it is inferior. It is recommended to bend the end of the wire repeatedly by hand. All products with soft hand feel, good fatigue strength, elasticity in plastic or rubber, and no crack on conductor insulator are excellent products. High quality welding wire is usually within the specified weight range. For example, ordinary plastic insulated single-stranded copper core wire has a cross-sectional area of 1.5mm2 and a weight of 100m1.8-1.9kg..
Selection of national standard wire
The copper core of qualified copper core wire should be purple-red, shiny and soft to the touch, while the copper core of fake copper core wire is purple-black, yellow or white, with many impurities, poor mechanical strength and toughness, which will break with a little force and often break wires. When checking, just peel off one end of the wire by 2cm, and then gently rub it on the copper core with a piece of white paper. If there is a black substance on the white paper, it means that there are many impurities in the copper core.
In addition, the insulation of fake and inferior wires seems to be very thick. In fact, most of them are made of recycled plastics. Over time, the insulation layer will age and leak electricity. Because of the low production cost of fake and shoddy wires, vendors often sell them at low prices under the guise of good quality and low price, which makes people fall for it. The wires with poor quality have insufficient weight or length, or the copper core of the wires has too many impurities.