Cables are the electrical products used for the transmission of electrical energy, the transfer of information and the conversion of electromagnetic energy. Wires and cables play an important role in all economic activities and social life. Wherever there is production, transport and economic activity, wires and cables are inseparable, so the quality of wire and cable directly affects our lives.
The main problems of substandard products exist in the structure, conductor size, conductor resistance, insulation and tensile strength of the sheath before ageing. Consumers using such products are prone to the dangers of leakage, electric shock and even fire, and these poor quality products have laid many hidden dangers for the normal operation of the power system.
1. After a single-phase grounding (short circuit) incident on a wire or cable, the relay protection device causes the cable to overheat due to failure to cut off the fault, resulting in spontaneous combustion of the insulation.
2. The tensile strength and elongation of the insulation sheath before aging greatly shortens the working life of the wire and cable. And it is easy to make the insulator fracture during construction or in long time energized and high temperature environment, resulting in exposed charged conductors and the risk of electric short circuit.
3. The conductor resistance is not qualified. Conductor resistance is an important indicator to check whether the conductor material and cross-section of the wire and cable are in compliance. When the conductor resistance exceeds the standard, it increases the loss of current through the wire and intensifies the heating of the wire and cable. The reason for the conductor resistance failure, mainly in order to reduce costs, the enterprise will account for 80% of the cost of raw materials, copper shrinkage, or reduce the cross-sectional area of the conductor, or the use of excessive impurities in recycled copper, so that the conductor resistance of wire and cable seriously exceeds the standard, in addition to the use of the process is prone to fire, but also accelerate the aging of the insulation layer covering the wire.
4. The insulation layer of the cable will gradually age in normal operation, and its service life is generally 15-20 years. If the wire is often overloaded or over-voltage due to long use, coupled with the thickness of the insulation layer not up to standard, improper installation (such as the bending radius of the cable is too small, the diameter of the wire protection tube is too small), it may cause accidents.
5. Substandard structure and dimensions. The main problem with structural dimensions is sheath thickness and insulation thickness. When the sheath and insulation thickness of the cable is not up to standard, the electrical strength of the wire and cable will be seriously reduced, resulting in a shortened service life of the wire and cable, which can seriously lead to wire and cable breakdown, the insulation (sheath) layer can not play a normal protective role, resulting in electrical short circuits and fire phenomena.
Shanghai Aein Wire&Cable Co., Ltd. focused on international standard cable manufacturing, with more than 100 invention and utility patents, is a member of the CableWire industries Association of Shanghai(CAS), and has participated in the preparation of several series of industry standards for special cables. We have a wide range of cables to meet the diverse needs of our customers and support customised solutions.
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