Advantages and disadvantages of copper and aluminum wires

2020-03-03 10:52:52 1035

Advantages of copper wire:

(1)Low resistivity: The resistivity of aluminum cable is about 1.68 times higher than that of copper cable.

(2)Good ductility: the elongation of copper alloy is 20 ~ 40%, the elongation of copper for electrical use is more than 30%, and that of aluminum alloy is only 18%.

(3) High strength: The allowable stress at room temperature is that copper is 7-28% higher than aluminum. Especially the stress at high temperature, the difference is even greater.

(4) Anti-fatigue: aluminum is easy to break after repeated bending, but copper is not easy. In terms of elasticity index, copper is also about 1.7 to 1.8 times higher than aluminum.

(5) Good stability and corrosion resistance: Copper wire is resistant to oxidation and corrosion, while aluminum wire is susceptible to oxidation and corrosion.

(6) Large current carrying capacity: Due to the low electrical resistivity, the copper wire cables with the same cross section are about 30% -50% higher than the current carrying capacity (maximum current that can be passed) of aluminum wire cables, especially more and more household appliances. , Home improvement basically uses copper wire.

(7) Low voltage loss: Because the resistivity of the copper wire cable is low, the same current flows in the same section. The voltage drop of the copper cable is small. Therefore, the same transmission distance can ensure higher voltage quality; or, under the condition of allowable voltage drop, the copper cable power transmission distance reaches a long distance, that is, the power supply coverage area is large, which is conducive to network planning and reduces Set number of power points.

(8) Low calorific value: at the same current, the calorific value of the copper wire cable with the same cross section is much smaller than that of the aluminum wire cable, which makes the operation safer.

(9) Low electrical loss: Due to the low electrical resistivity of copper, it is obvious that copper cables have lower power loss than 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 wire cable is stable, and no accident will occur due to oxidation. The joints of aluminum cable are unstable, and often the contact resistance increases due to oxidation, which causes heat and accidents. Therefore, the accident rate is much higher than that of copper cable. Especially in some places where copper and aluminum wires are connected, problems will occur as long as they are not connected for a long time. Therefore, the copper and aluminum wires must be connected strictly.

(11) Convenient construction:

① The copper wire has good flexibility and small allowable bending radius, so it is convenient to turn and easy to pipe.

② The copper wire is resistant to fatigue and is not easy to break after repeated bending, so the wiring is convenient;

③ The copper wire 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.


Disadvantages of copper wire:


The high price of copper wire and the large proportion of copper wire determine the high cost of copper wire. As a cable, there are many advantages in performance, which is high cost! So our common overhead wires basically do not use copper wires, which is good or too heavy, so overhead wires often use more aluminum wires, and ground wires usually use copper wires.

Advantages and disadvantages of aluminum wire:

The high price of copper wire and the large proportion of copper wire determine the high cost of copper wire. As a cable, there are many advantages in performance, which is high cost! So our common overhead wires basically do not use copper wires, which is good or too heavy, so overhead wires often use more aluminum wires, and ground wires usually use copper wires.

1. Advantages and disadvantages of aluminum wire:

(1) Cheap: Copper rods are 3.5 times the price of aluminum rods, and copper's specific gravity is 3.3 times that of aluminum. Therefore, aluminum cables are much cheaper than copper cables, which is suitable for low-cost projects or temporary electricity.

(2) The cable is very light: the weight of the aluminum cable is 40% of that of the copper cable, and the construction and transportation costs are low.

(3) Anti-oxidation and corrosion resistance: Aluminum reacts quickly with oxygen in the air to form an oxide film, which can prevent further oxidation. Therefore, aluminum wire is a necessary material for high-voltage, large-section, long-span overhead power transmission. These advantages no longer exist for low-voltage lines.

Disadvantages of aluminum wire:

Aluminum wire has low conductivity, large electrical loss, poor tensile strength, low corrosion resistance, and the joint part is particularly susceptible to oxidation. If it is connected to copper wire, the joint part is more prone to corrosion due to the potential difference, and it is easy to cause open circuit estimation . These are relative to the use of low-voltage lines, but the advantages of aluminum wires on high-voltage lines are also quite obvious. We must figure this out, and we cannot assert it across the board.


Advantages and disadvantages of copper and aluminum wires