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The national standard line is 100 ± 0.5 meters / roll, and some non-standard lines are only more than 80-95 meters / roll, generally 95 meters. 95 line refers to this kind of non-standard line with 95 meters marked with 100 meters.

one

It depends Check whether there is quality system certification; Check whether the certificate of conformity is standardized; Check whether there is factory name, address, inspection seal and production date; Check whether the trademark, specification, voltage, etc. are printed on the wire. It also depends on the cross section of the copper core of the wire. The superior red copper has bright color and soft color, otherwise it is inferior.

two

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

three

weighing. Wires of good quality are generally within the specified weight range. For example, the commonly used cross-sectional area is 1.5

Mm2 plastic insulated single strand copper core wire, per 100

M weight is 1.8 ~ 1.9

kg; two point five

Mm2 plastic insulated single strand copper core wire, per 100

M weight is 3 ~ 3.1

kg; four

Mm2 plastic insulated single strand copper core wire, per 100

M weight is 4.4 ~ 4.6

Kg, etc. The wire with poor quality has insufficient weight, or insufficient length, or excessive impurities in the copper core of the wire.

four

Look at copper. Qualified copper core wire copper core should be purplish red, shiny and soft. The copper core of the fake copper core wire is purple black, yellowish or white, with many impurities, poor mechanical strength and toughness. It will break with a little force, and there are often wire breaks in the wire. 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 substance on the white paper, it indicates that there are more impurities in the copper core. In addition, the insulation layer of fake and shoddy wires seems to be very thick. In fact, most of them are made of recycled plastic. Over time, the insulation layer will age and leak electricity.

five

Look at the price. Due to the low production cost of fake and shoddy wires, vendors often sell at low prices under the guise of low price and good quality, which deceives people.