What is the national standard wire!

People who have been in contact with the wire and cable industry know more or less that there are national standard lines and non-standard lines in the wire and cable industry. The existence of non-standard line has seriously threatened the safety of people's lives and property, and many tragic fires caused by non-standard line are always alerting us. Non standard line is not only a problem in the wire and cable industry, but also a problem closely related to people's lives and property. It is our duty to strike and resist non-standard line.

National standard wire and cable:

That is, the wire is produced completely according to the national standard. General household and common wires are of standard specification and performance, and the national standard stipulates five common specifications and performance.

2. Main measurement criteria:

1. Appearance standard, the wire must have certification mark, manufacturer, wire diameter, etc., and the ground wire shall be yellow green insulating layer

2. Mechanical strength

3. Insulation of sheath (generally more than 100m Ω) and withstand voltage strength (below 500V, 1500V)

4. Line resistance (no more than a certain resistance under a certain wire diameter, conductivity and length)

5. Under 150 ℃ high temperature impact and - 30 ℃ low temperature, the wire shall not crack

The distinction between three national standards and non national standards:

The national standard line top grade product is 100 ± 0.5 m / roll, and some non-standard lines are only 80-95 M / roll, generally 95 m is in the majority. 95 line refers to this kind of 95 m non-standard line marked with 100 m.

1. Check whether there is quality system certification; check whether the certificate is standard; check whether there is factory name, address, inspection seal and production date; check whether there is trademark, specification and voltage printed on the wire. But also look at the cross-section of the wire copper core, superior copper color bright, soft color, otherwise it is inferior.

2. Try. Take a wire head and bend it repeatedly by hand. Those with soft handle, good fatigue resistance, high elasticity of plastic or rubber handle and no crack on the wire insulator are excellent products.

Three weights. Good quality wires are generally within the specified weight range. For example, the weight of the commonly used plastic insulated single strand copper wire with a cross-sectional area of 1.5 mm2 is 1.8-1.9 kg per 100 m; the weight of the plastic insulated single strand copper wire with a cross-sectional area of 2.5 mm2 is 3-3.1 kg per 100 m; the weight of the plastic insulated single strand copper wire with a cross-sectional area of 4.0 mm2 is 4.4-4.6 kg per 100 m. The weight of the poor wire is not enough, or the length is not enough, or the copper core of the wire is too much impurity.

Look at the copper. Qualified copper wire copper core should be purplish red, glossy and soft. The copper core of the fake copper wire is purple black, yellow or white, with many impurities, poor mechanical strength and poor toughness. It will break with a little force, and the wire is often broken. When checking, you just peel off one end of the wire for 2 cm, and 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 insulation layer of fake 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.

5. Look at the price. Because of the low production cost of fake wires, vendors often sell them at low prices under the guise of low price and good quality.