The national standard wire is the wire produced in full accordance with the national standard. General household, common wires are standard specifications of performance, the national standard specifies the common 5 specifications of performance.

1, appearance standard, the wire must have certification mark, manufacturer, wire diameter, etc., ground wire with yellow green insulation

2. Mechanical strength

3, the insulation of the sheath (generally greater than 100MΩ) and compressive strength (500V below 1500V)

4, wire resistance (a certain wire diameter, conductivity, length is not greater than a certain resistance)

5, high temperature impact 150 degrees, low temperature -30 degrees under the wire shall not crack.

distinguish

1, to see

See whether there is a quality system certificate, see whether the certificate is standardized; See whether there is a factory name, factory address, inspection seal, production date; See if the wire is printed with trademarks, specifications, voltage, etc. Also look at the cross section of the wire copper core, excellent copper color bright, soft color, otherwise it is defective.

2. Experiment

It is advisable to bend a wire head repeatedly by hand, and those with soft feel, good fatigue strength, large plastic or rubber feel elasticity and no cracks on the wire insulator are excellent products.

3. Weigh

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

4. Look at the copper

Qualified copper wire copper core should be purple, shiny, soft. The shoddy copper core wire is purplish black, yellow or white, many impurities, poor mechanical strength, poor toughness, a little force will break, and the wire is often broken. When checking, you just peel off one end of the wire 2 cm, and then rub a piece of white paper on the copper core slightly, if there is black material on the white paper, it means that there are more impurities in the copper core. In addition, the insulation layer of shoddy wire seems to be very thick, in fact, most of them are made of recycled plastic, and over time, the insulation layer will age and leak electricity.

5. Look at the price

Because of the low production cost of fake and shoddy wires, vendors often sell at low prices under the guise of cheap and good quality, so that people are fooled.