In recent years, with the emergence of copper-clad aluminum cables, the price of pure copper cables, which was originally expensive, has also become people-friendly, which has promoted the development of China's wire and cable industry in a certain sense. Copper-clad aluminum is concentrically coated with a copper layer on the surface of the aluminum or aluminum/steel alloy core material, which is drawn and the thickness of the copper layer is more than 0.55mm. What is the difference between copper-clad aluminum cable and pure copper cable in terms of performance, what are the advantages, and what are the shortcomings?
at In terms of mechanical properties, the strength and elongation of pure copper conductors are greater than those of copper-clad aluminum conductors, which means that pure copper is better than copper-clad aluminum in terms of mechanical properties. From the perspective of cable design, pure copper conductors have better mechanical strength than copper-clad aluminum conductors points, not necessarily needed in the actual application process. Copper-clad aluminum conductors are much lighter than pure copper, so copper-clad aluminum cables are lighter than pure copper conductor cables in terms of overall weight, which will bring advantages to cable transportation and cable racking facilities Convenient. In addition, copper-clad aluminum is a little softer than pure copper, and the cable produced with copper-clad aluminum conductor is a little better than pure copper cable in terms of flexibility.
In terms of electrical properties, because the conductivity of aluminum is worse than that of copper, copper-clad aluminum is made The DC resistance of the conductor is larger than that of the pure copper conductor, which mainly depends on whether the cable will be used for power supply, such as providing power to the amplifier, if it is used to supply power, the copper-clad aluminum conductor will cause additional power consumption, voltage Lowered more. When the frequency exceeds 5MHz, there is no noticeable difference in the AC resistance attenuation between these two different conductors. Of course, this is mainly due to the skin effect of high-frequency current, the higher the frequency, the flow of current The closer it is to the surface of the conductor, the surface of the copper-clad aluminum conductor is actually pure copper material, and when the frequency is high to a certain point, the whole current is plated in the copper material and flows. In the case of 5MHz, the current is approximately 0.025 mm thickness, while copper-clad aluminum conductors have about twice the thickness of the copper layer. For coaxial cables, because the transmitted signal is above 5MHz, copper-clad aluminum conductors and pure copper conductors transmit the effect is the same. This can be demonstrated in the actual test of cable attenuation.
In terms of economy, copper-clad aluminum conductors are sold by weight, pure copper conductors are also sold by weight, and the price of copper-clad aluminum conductors is high It is a bit more expensive than pure copper conductors of the same weight. But the same weight of copper-clad aluminum is much longer than the length of pure copper conductors, and the cable is calculated by length. The same weight copper-clad aluminum cable is 2.5 times the length of the copper wire, and the price is only one A few hundred dollars more per ton. Taken together, copper-clad aluminum cables are very advantageous. Because the copper-clad aluminum cable produced by Asian cable is relatively light, the transportation cost, installation and erection cost of the cable will be reduced, and the construction belt will be given Come to a certain convenience.
Copper-clad aluminum cable is also a good way to relieve the current pressure on enterprises, aluminum wire outer bread a layer of copper drawn bimetallic wire, due to the advantages of small specific gravity, good transmission performance and other advantages, especially suitable for making RF coaxial cables of inner conductors, compared with pure copper wire, its density is about 40% pure copper. The transmission characteristics are better than pure copper wires, and it is the most ideal conductor in the RF coaxial cable branch line.