It is recommended to select products manufactured by reputable manufacturers and vendors. Wires packaged in coils should be accompanied by a certificate of conformity; the wire itself should bear printed markings indicating the manufacturer's name or trademark, voltage rating, and the 3C certification mark. Counterfeit and substandard wires often lack clear information, or their labeling may be ambiguous-for instance, merely stating "Made in China" or listing a specific province or city-which is tantamount to failing to specify a concrete place of origin.
The primary conductor materials used in wiring installations are copper and aluminum. When making a purchase, one should select the appropriate specifications based on the electrical load requirements. For example, lighting circuits can utilize 1.5 mm² copper wire or 2.5 mm² aluminum wire, while appliances such as air conditioners and microwave ovens may require 2.5 mm² copper wire or 4 mm² aluminum wire. Selecting the appropriate specifications helps prevent short circuits or fires caused by insufficient current-carrying capacity. Furthermore, attention should be paid to the quality of the conductor material; high-quality copper-core wires typically utilize copper that is purplish-red in color, lustrous, and soft to the touch. In contrast, the copper cores of substandard products may appear purplish-black, yellowish, or whitish; they often contain high levels of impurities, possess poor mechanical strength and ductility, and are prone to breakage-specifically, the individual strands within a multi-strand wire may snap, thereby compromising the wire's service life.
The outer sheath of wiring cables typically consists of polyvinyl chloride (PVC) insulation material. In high-quality wires, the insulation layer appears smooth, and the printed markings are crisp and legible. When viewed in cross-section, the insulation layer should be of uniform thickness and free from eccentricity (i.e., the conductor should be centered within the insulation). While the insulation layers of some substandard wires may appear thick, they are often manufactured using recycled plastics; over time, these materials are prone to aging, which can lead to electrical leakage.
When purchasing, the following methods can also be employed to assist in assessing quality. Observe the surface of the insulation layer to check for uniform thickness and the absence of defects. National standards stipulate specific requirements regarding wire length and conductor diameter; for instance, a standard BV 2.5 mm² wire should measure 100 meters in length, with a conductor diameter of approximately 1.78 mm. Significant deviations from these specifications may indicate that the product fails to meet quality standards. Additionally, high-quality copper material typically exhibits a reddish-purple hue and possesses a relatively soft texture [3].
4. High-quality wires typically fall within a prescribed weight range. Counterfeit and substandard products, due to their lower production costs, are often sold on the market at significantly lower prices.