We all know that copper and aluminum are the most commonly used conductors for wires and cables. Do you know what advantages copper core cables have over aluminum core cables?
- Low resistivity and low energy consumption: The resistivity of copper cables is 1.68 times lower than that of aluminum cables, and the power loss is low. This is conducive to improving the utilization rate of power generation and protecting the environment.
- Good ductility: The ductility of electrical copper is above 30%, while that of aluminum alloy is only 18%.
- High strength: The allowable stress at room temperature is 7~28% higher for copper than for aluminum. Especially at high temperatures, the stress is far different.
- Anti-fatigue: Copper is not easy to break after repeated bending, while aluminum is easy to break after repeated bending. In terms of elasticity index, copper is also about 1.7~1.8 times higher than aluminum.
- Good stability and corrosion resistance: Aluminum core is easy to oxidize and corrode, while copper core is relatively stable and has strong anti-oxidation ability.
- Large current carrying capacity: Copper core has low resistivity, so the current carrying capacity (i.e. the maximum current that can pass) of copper core cable is 30% higher than that of aluminum core.
- Convenient construction: ① The copper core has good flexibility and a small allowable bending radius, so it is easy to turn and pass through the pipe; ② The copper core is fatigue-resistant and not easy to break after repeated bending, so it is convenient to connect the wires; ③ The copper core has high mechanical strength and can withstand large mechanical tension, which brings great convenience to construction and laying, and also creates conditions for mechanized construction.
- High safety: The connector of copper core cable has stable performance and will not cause accidents due to oxidation. The unstable connector of aluminum core cable often causes accidents due to oxidation, which increases the contact resistance and heats up. Therefore, the accident rate is much higher than that of copper core cable.
What are the advantages of aluminum core cable?
- Cheap price: Copper rod is more than 3 times the price of aluminum rod, and copper is 3.3 times heavier than aluminum, so aluminum core cable is much cheaper than copper core cable, suitable for low-cost projects or temporary power supply.
- The cable is very light: The weight of aluminum core cable is 40% of that of copper core cable, and the construction and transportation costs are low.
- Anti-oxidation: Aluminum reacts quickly with oxygen in the air to form an oxide film that prevents further oxidation, so aluminum conductors are the must-have material for high-voltage, large-section, and large-span overhead power transmission.
Although aluminum cables are relatively cheap, copper cables have the characteristics of low accident rate, corrosion resistance, high reliability, and convenient construction and maintenance in cable power supply, especially in the field of underground cable power supply. This is also the reason why copper cables are currently mainly used in China, especially for home decoration wires.