People who are in contact with the wire and cable industry are more or less aware that there is a national standard line and a non - marking line in the wire and cable industry. Non marking, has been a serious threat to people's life and property safety, because many tragic fire caused by non marking also alert us at the moment, non marking is not only the wire and cable industry problems, but is closely related to people's life and property, and resist against non marking, it is our duty to every person should do the.

A national standard wire and cable:
It is the electric wire that is produced according to the national standard. General household and common wire are standard specifications and performance, the national standard stipulates the common 5 specifications and performance.
Two the main criteria of measurement:
1. the appearance standard, the wiring must have the certification mark, the manufacturer, the line diameter and so on, the ground wire uses the yellow green insulating layer
2. mechanical strength
3. insulation (generally greater than 100M omega) and pressure resistance (below 500V 1500V)
4. wire resistance (certain line diameter, conductivity, length is not greater than a certain resistance)
5. under the high temperature impact of 150 degrees, the wire shall not appear cracking at low temperature -30 degrees.
The distinction between the three countries and the non national standards:
The top quality products of GB line are 100 + 0.5 m / roll, and no marking line. Some of them are only 80-95 M / V, generally 95 m, and the 95 line is 95 m, which is marked 100 m.
1, we need to see whether there is quality system certification, see whether the qualification certificate is standardized, see whether there are factory names, factory locations, inspection chapters and production dates, and see whether there are trademarks, specifications, voltage and so on. Also look at the cross section of wire copper core, the superior products of copper bright color, color and lustre, otherwise it is the secondary.
2 to try. It is advisable for a wire head to be repeatedly bent by hand, which is soft and anti fatigue strength, plastic or rubber feel elastic and no cracks on wire insulation are excellent products.
3 weigh the weight. Good quality wires are generally within the specified weight range. For example, the commonly used plastic insulated single strand copper core with a cross-sectional area of 1.5 mm2, the weight of every 100 m is 1.8 to 1.9 kg; the 2.5 mm2 plastic insulated single stranded copper core line, each 100 m weight is 3 ~ 3.1 kg; 4 mm2 plastic insulated single stranded copper conductor, 100 m weight is 4.4 to 4.4 kg. Poor quality wires are not enough, either the length of the wire is not enough, or the copper core of the wire is too much.
4 look at the copper. The copper core copper core of the qualified copper core should be purple red, luster and soft hand. However, the copper core of fake and inferior copper core is purple black, yellowish or partial white. There are many impurities, poor mechanical strength and poor toughness. It will break if a little force is applied, and the wire break phenomenon often occurs. When checking, you just peel the wire 2 cm, then rub it on the copper core with a piece of white paper. If there is black substance on the white paper, it means that there are more impurities in the copper core. In addition, the insulating layer of the fake and shoddy wires seems to be very thick. In fact, most of them are made of recycled plastic, with a long time, and the insulation layer will be aging and leakage.
5 look at the price. As the cost of making fake and shoddy wires is low, the sellers often sell at low price under the guise of good price and beauty.