How to Identify the Quality of the National Standard Power Cord

National standard wire: It is the wire that is produced in full accordance with the national standard. General household and common wires have standard specifications. The national standard specifies 5 common specifications.

Metrics:

• Appearance standard, there must be certification mark, manufacturer, wire diameter, etc. on the wire, and the ground wire uses a yellow-green insulation layer;
• Mechanical strength;
• Insulation (generally greater than 100MΩ) and compressive strength (1500V below 500V) of the sheath;
• Wire resistance (no more than a certain resistance under a certain wire diameter, conductivity, and length);
• Under the high temperature impact of 150 degrees, the wire shall not be cracked under the low temperature of -30 degrees.

The distinction between national standard and non-national standard:

The premium products of the national standard line are 100±0.5 meters/roll, and some of the non-standard lines are only more than 60-75 meters/roll.

To see

It depends on whether there is a quality system certification, whether the certificate is standardized, whether there is a factory name, site, inspection stamp, production date, and whether there are trademarks, specifications, voltages, etc. printed on the wires. It also depends on the cross section of the copper core of the wire. The high-quality copper is bright in color and soft in color, otherwise it is inferior.

To try

It is preferable to bend a wire head repeatedly by hand. Anything with soft hand feeling, good fatigue resistance, elastic hand feeling of plastic or rubber and no cracks on the wire insulator is the superior product.

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 has a weight of 1.8 to 1.9 kg per 100 m; a 2.5 mm² plastic insulated single-strand copper core wire has a weight of 3~3.1 per 100 m. kg; 4.0 mm2 plastic insulated single-strand copper core wire, weighing 4.4 to 4.6 kg per 100 m. Poor quality wires have insufficient weight, either the length is not enough, or the copper core of the wires is too impurity.

Look at the quality of copper

The copper core of the qualified copper core wire should be purple-red, shiny and soft to the touch. The fake and inferior copper core wire is purple-black, yellowish or white, with many impurities, poor mechanical strength, poor toughness, and it will break with a little force, and there are often disconnections in the wire. When checking, you just need to peel the wire 2 cm off one end, and rub a piece of white paper on the copper core. 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 fake wires seems to be very thick, but in fact, most of them are made of recycled plastics. Over time, the insulating layer will age and cause leakage.

Price

Due to the low production cost of counterfeit and shoddy wires, vendors often sell them at low prices under the guise of low prices and good quality when selling, which makes people fooled.