The most commonly used cable conductors are copper and aluminum. Now we will compare them in terms of conductor performance, so that you can choose the right cable products correctly.
1. Advantages of copper core cables
1. Low resistivity: The resistivity of aluminum core cable is about 1.68 times higher than that of copper core cable.
2. Good ductility: The ductility of copper alloy is 20~40%, the ductility of electrical copper is above 30%, while that of aluminum alloy is only 18%.
3. High strength: the allowable stress at room temperature, copper is 7~28% higher than that of aluminum. Especially the stress at high temperature, the difference between the two is even greater.
4. Anti-fatigue: aluminum is easy to break after repeated bending, but copper is not. In terms of elasticity index, copper is also about 1.7~1.8 times higher than that of aluminum.
5. Good stability and corrosion resistance: The copper core is oxidation-resistant and corrosion-resistant, while the aluminum core is susceptible to oxidation and corrosion.
6. Large current carrying capacity: Due to the low resistivity, the copper core cable with the same cross-section is about 30% higher than the allowable current carrying capacity (the maximum current that can pass through) of the aluminum core cable.
7. Low voltage loss: Due to the low resistivity of the copper core cable, the same current flows through the same section. The voltage drop of copper core cable is small. Therefore, the same power transmission distance can ensure higher voltage quality; in other words, under the condition of allowable voltage drop, the copper core cable can transmit power to a longer distance, that is, the power supply coverage area is large, which is conducive to network planning and reduces Set number of power supply points.
8. Low heating temperature: Under the same current, the heating value of the copper core cable with the same section is much smaller than that of the aluminum core cable, making the operation safer.
9. Low energy consumption: Due to the low resistivity of copper, it is obvious that copper cables have low power loss compared to aluminum cables. This is conducive to improving the utilization rate of power generation and protecting the environment.
10. Anti-oxidation and corrosion resistance: The performance of the connector of the copper core cable is stable, and there will be no accidents due to oxidation. The joints of aluminum core cables are often unstable due to oxidation, which increases the contact resistance and generates heat, resulting in accidents. Therefore, the accident rate is much larger than that of copper core cables.
11. Convenient construction: ①The copper core is flexible and the allowable curvature radius is small, so it is convenient to bend and pass through the pipe; ②The copper core is fatigue-resistant and not easy to break after repeated bending, so the wiring is convenient; ③The mechanical strength of the copper core is high, It can withstand large mechanical tension, which brings great convenience to construction and laying, and also creates conditions for mechanized construction.
Second, the advantages of aluminum core cable
1. The price is cheap: the copper rod is 3.5 times the price of the aluminum rod, and the proportion of copper is 3.3 times that of the aluminum, so the aluminum core cable is much cheaper than the copper core cable, which is suitable for low-cost projects or temporary electricity.
2. The cable is very light: the weight of the aluminum core cable is 40% of that of the copper core cable, and the construction and transportation costs are low.
3. Anti-oxidation and corrosion resistance: Aluminum reacts with oxygen in the air to quickly form an oxide film, which can prevent further oxidation, so aluminum wire is a must-have material for high-voltage, large-section, long-span overhead power transmission.
Although aluminum core cables are cheap and cheap, copper cables have outstanding advantages in cable power supply, especially in the field of underground cable power supply. The use of copper core cables for power supply underground has the characteristics of low accident rate, corrosion resistance, high reliability, and convenient construction and maintenance. This is also the reason why copper cables are mainly used in underground cable power supply in China.