Firstly, there are six points to distinguish between "national standard" and "non-standard" cables: (1) observation, (2) testing, (3) weighing, (4) comparing prices, (5) examining copper quality, and (6) quality inspection.

(1) Look: It means to lookwire and cableWhether the product has a quality system certification, whether the certificate of conformity is standardized, whether there is a factory name, address, inspection seal, and production date, and whether there are trademarks, specifications, and voltage printed on the wires. Finally, we also need to look at the cross-section of the copper core of the wire. High quality purple copper has a bright and soft color, otherwise it is a defective product.

(2) Trial: Refers to repeatedly bending a wire end by hand. Any product that feels soft and has good fatigue resistance, as well as plastic or rubber with high elasticity and no cracks on the wire insulation, is considered superior.

(3) Weighing: High quality wires and cables generally weigh within the specified range every 100 meters. For example, commonly used plastic insulated single stranded copper core wire with a cross-sectional area of 1.5mm2; 1.8-1.9kg per 100m; 2.5mm2 plastic insulated single stranded copper core wire; Plastic insulated single stranded copper core wire with a weight of 3-3.1kg4.0mm2 per 100m and 4.4-4.6kg per 100m, etc. Poor quality wires will have insufficient weight, either due to insufficient length or excessive impurities in the copper core of the wire.

If it is a cable, especially a large-sized cable, the weighing method is a simple way to reflect whether the cable meets the copper content standard and whether the conductor cross-section is sufficient. Generally, cables with small cross-sections made by stealing copper can be considered non-standard if the copper content of the cable falls below the weight range allowed by national specifications and standards.

(4) Comparison: Due to the low production cost of fake and inferior wires and cables, vendors often sell them at low prices under the guise of good quality and low price, which can deceive people. Therefore, when purchasing cables, be careful not to be deceived by the seller's claim of 'good value for money' cables, and be tempted by cheap prices.

(5) Check the copper quality: A qualified copper core wire should have a purple red color with luster and a soft touch when touched. Poor quality copper core wires have a color of purple black and yellowish or white, with many impurities and poor mechanical strength and toughness, and can break with just a little force. And there are often broken wires inside the wires. When checking, you just need to peel off one end of the cable and rub a piece of white paper slightly on the copper core. If there is black substance on the white paper, it indicates that there are more impurities in the copper core, and it can be identified as a 'non-standard' wire and cable.

(6) Quality inspection: In case of differences in cable quality, it can be sent to a third-party testing agency for inspection. Use the inspection report as the basis for determining whether the cable is qualified.