It may be more difficult to find out whether the cable is full of meters because customers generally do not have the equipment to measure the meters, and the same method can be used to determine whether the cable is full of meters. It is also a good way to print the rice mark when the factory produces. However, it should be noted that there is no way to print the rice mark on the line with the diameter less than 5mm.
Square copper is a kind of precious metal. If the copper diameter is deficient, a large amount of raw material cost can be reduced. In this way, micrometer is needed to measure the diameter of copper wire. If you don't have a micrometer, it's easier to weigh a whole coil of wire to see if it's much lighter than a good cable. Or refer to the nominal weight given by the factory. The nominal weight given by some factories is too low to guarantee the product quality.
How to identify the internal quality of wires and cables:
High quality copper cable uses high purity oxygen free copper, copper core color is bright, poor copper wire surface is relatively dark.
Plastic plastic uses high-quality primary plastic, good bending performance, bending cable will not produce texture, poor recycled plastic will appear obvious texture after bending several times, and fracture occurs after many times of bending.
Auxiliary materials in order to ensure the roundness of the cable, for multi-core cables, fillers will be added to the core, and the sheath thickness is relatively thick. If the cable is not round, it means that the filler is little and the sheath is thin.
Bundle wire multi strand copper wire will be bundled in production to improve the tensile performance, roundness, electrical performance and tightness with the insulation layer of copper core. However, due to the increase of copper consumption, many factories have omitted this step. The resolution method is to cut open the core wire of the cable to see whether the copper wires inside are regularly twisted together.
Braided cable with copper mesh braided layer, the braided layer accounts for a large part of the cost of cable raw materials, and the coverage rate of braided layer directly affects the electrical performance of the cable. At the same time, the tight braided layer can increase the strength of the cable, and the wire and cable can reduce the decline of the electrical and pneumatic performance of the cable in the bending state. Therefore, it is an important means to distinguish the advantages and disadvantages of cables to see whether the braided layer has high coverage and uniform and fine braiding.