Cable is an important bridge for power transmission and information transmission. However, some people always buy unqualified cables and wires because of cheap prices, and even some companies supply unqualified wires and cables in order to obtain more benefits. These products are used in a large area, and the consequences will be unimaginable in the event of fire or electricity leakage. The hazards of unqualified cables include:
1. In order to reduce costs, some companies shrink the copper material, which accounts for 80% of the raw material cost, either reduce the cross-sectional area of the conductor, or use recycled copper with excessive impurities, which causes the wire and cable conductor resistance to seriously exceed the standard and produces conductor resistance. Unqualified cable. When the resistance of the conductor exceeds the standard, the loss when the current passes through the line is increased, and the heating of the wire and cable is exacerbated. In addition to being prone to fire during use, it will also accelerate the aging of the insulating layer covering the wire.
2. Wires and cables with unsatisfactory tensile strength and elongation before the aging of the insulation sheath directly greatly shorten the working life of the wires and cables, and are prone to appear during construction or in a long-time energized and high temperature environment The insulator breaks, leaving the live conductors exposed, resulting in the risk of electric shock short circuit.
3. Cables with unqualified marks are easy to cause identification errors of construction personnel, which may cause electrical accidents in serious cases. The mark is the main way to identify the basic information of wire and cable products, and is an important basis for selecting wire and cable products. The main contents of the standard cable marking are: product models, specifications, standard numbers, factory names, places of production, etc. have a certain range of use.
4. The main problem of wire and cable with unqualified structural size is that the thickness of the sheath and insulation of the cable is not up to the standard. It will cause the electrical resistance of the wire and cable to be seriously reduced, resulting in a shortened service life of the wire and cable. In severe cases, it may cause the wire and cable to be broken down, and the insulation (sheath) layer does not provide normal protection, resulting in electrical short circuits and fires. .