What effect does temperature have on the performance of power cords

As an important part of connecting power supply and electrical equipment, the performance of power cord has a direct impact on the safety and stability of the equipment. Temperature is one of the key factors affecting the performance of power cord. The performance of power cord in high or low temperature environment is significantly different, which will have a profound impact on its conductivity, insulation and mechanical strength.

Conductive performance
The conductivity of power cord is closely related to the resistance of the material used. Copper and aluminum are commonly used conductor materials for power cords, and the resistance of these materials changes with temperature. According to the principles of physics, the resistance of metals increases with increasing temperature. This means that in high temperature environments, the current carrying capacity of power cords may decrease, resulting in increased power loss and increased heating. For example, the resistivity of copper is about 1.68×10^-8 Ω·m at 20°C, while at 100°C, the resistivity will increase by about 1.5 times. This increase in resistance will cause more heat to be generated when current passes through, forming a vicious cycle. Therefore, in high temperature environments, the rated current carrying capacity of power cords must be re-evaluated to avoid overload and potential fire risks.

Insulation performance
The insulation layer of the power cord is an important part of protecting the conductor and preventing leakage. The performance of insulating materials can show significant differences under different temperature conditions. High temperature can intensify the movement of insulating material molecules, causing them to age, degrade or even melt, thereby reducing the insulation performance. Common insulating materials such as polyvinyl chloride (PVC), polyethylene (PE) and cross-linked polyethylene (XLPE) have different heat resistance and aging rates in high temperature environments. For example, the heat resistance of PVC is usually around 70°C. After exceeding this temperature, its insulation performance decreases significantly, increasing the risk of leakage or short circuit. In contrast, cross-linked polyethylene (XLPE) has higher heat resistance and can usually work stably in environments between 90°C and 120°C. Therefore, in high temperature environments, it is crucial to choose the right insulating material.

In low temperature environments, insulating materials are also affected. Some insulating materials may become brittle at low temperatures, increasing the risk of cracking. At this time, cracks may appear in the insulation layer of the power cord, causing leakage or short circuit. Therefore, in extreme low temperature environments, power cords suitable for low temperature operation should be selected to ensure the effectiveness of their insulation performance.

Mechanical strength Temperature fluctuations also affect the mechanical strength of the power cord. In high temperature environments, the insulating material may soften, resulting in a decrease in the tensile strength and bending resistance of the power cord. In this case, the power cord is more likely to break or be damaged when subjected to mechanical stress (such as stretching, bending or compression). In low temperature environments, the toughness of some materials may decrease, becoming more fragile and easily broken under external forces. Therefore, when selecting a power cord, the temperature range of the use environment must be fully considered to ensure that its mechanical strength can meet actual needs.