Wires and cables are the main carriers of power transmission and are widely used, especially in the transformation and new construction of urban and rural power grids. For this reason, this article specifically analyzes and identifies some inferior products based on several types of wires and cables with relatively high demand in the market.
Generally speaking, the authenticity of insulated wires sold or used on the market is mainly determined by the labels, logos and 3C marks on the products or packaging. However, judging from the actual purchase situations of users, many insulated wires have 3C marks on their products or packaging even if they have quality problems. Therefore, it is difficult to find out whether there are any problems at the moment. In such a case, you cannot easily believe it.
Poor quality wires are very harmful. First, the safety performance is low. The insulation layer of many wires is not made of regular insulating plastic, but made of recycled plastic. The insulation layer can be peeled off at will, which can easily cause the insulation layer to be broken down by current and leak, which will also pose a great threat to human life safety. Second, the thickness of the conductive inner conductor determines the load of the wire on the current. The larger the current, the thicker the conductive inner core is required.
During the inspection, it was found that the actual cross-sectional area of the core of many wires was much smaller than the size indicated. For example, many wires claimed that the core cross-sectional area was 4 square millimeters, but when measured, it was only 2.5 square millimeters, and some were even only 1.5 square millimeters. When users use such products, it will cause excessive resistance and heat, causing the risk of electrical fire.
Poor quality wires can cause the insulator to break, exposing the live conductor, which can easily lead to the risk of electric shock, short circuits, power outages, damage to electrical equipment, and even fire and other serious consequences.
There are several ways and techniques to identify inferior insulated wires:
A. Look carefully at the printed label. If the words are blurred or unclear, it means to look at the printed words on the label and the insulation cover. If there are typos or the printing depth is different or the words are blurred, you should pay attention.
B. Rub the insulation with your hands, and the color and characters will fade, which indicates poor quality. This means rubbing the insulation with your fingers. Some inferior insulation wires are prone to discoloration, especially red wires. If the color of the wire remains on your fingers or the characters printed on the wire are wiped off after rubbing, it is generally a poor quality wire.
C. Use your fingernails to scratch or pinch the wire. If you scratch or pinch off a piece of the insulation, it is generally a poor quality wire.
D. Repeated bending of insulated wires will break after three to four times. This means that the insulation layer of inferior wires is generally made of poor quality and will break after 3 to 4 times of bending.
E. Use fire to ignite the wire insulation, and the wire will spontaneously combust without the open flame. This means that the insulation layer is ignited, and the wire that can spontaneously combust without the open flame is a low-quality wire.
F. The core of the wire is usually made of aluminum and copper, which makes the color darker and less shiny. This refers to the color of the core of the wire. The inferior wire is dark in color and has no metallic luster.
G. Measure the inner diameter and outer diameter carefully, and check the weight before weighing. If the above 6 methods still cannot determine, you can also measure the outer diameter and core diameter of the insulated wire. The allowable error is ±10%. If the measured value exceeds the allowable error, it is basically a low-quality insulated wire.
