Why is the copper braided wire tinned and its current carrying capacity high or low?
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Copper braided wires, copper bars, and copper cables have the same effect, and they can all be used as copper wires for various equipment connections, especially in some high-voltage power transmission equipment. So who knows which of the three products has a stronger current-carrying capacity? And why do they all have to be tinned?
The reason why it is necessary to tinn copper braided wires, copper bars, copper cables, etc., is mainly to prevent copper oxidation, although the conductivity of burning copper itself is good, but it is easy to oxidize, which will affect the conductivity, so it is generally silver plating or tin plating to prevent copper oxidation, but silver is more expensive, so tin plating slowly replaces silver plating has become a trend.
The current-carrying capacity of copper braided wire, copper bar and copper cable is related to many factors, such as short distance and small load according to the heating conditions to select the wire cross-section with the heating condition of the wire to control the current, the smaller the cross-sectional area, the better the heat dissipation, and the greater the current passing through the unit area.
On the basis of safe ampacity for long-distance and medium-load loads, it is necessary to select copper braided wires, copper bars, and copper cable wire cross-sections according to voltage loss conditions, and it is not enough for long-distance and medium-load only not to heat up, but also to consider voltage loss, to ensure that the voltage to the load point is within the qualified range, and the electrical equipment can work normally.
When under the condition of large load, it is necessary to select according to the economic current density on the basis of the qualified safe current carrying capacity and voltage drop, and at the same time consider the power loss, which requires the power loss and capital investment to be within a reasonable range. In order to ensure the continuous operation of the wire for a long time, it is also determined by comprehensive factors such as the extreme temperature, cooling conditions, and laying conditions of the core use environment of the wire.
Under normal circumstances, the conductivity of copper braided wire is stronger when the distance is short, the cross-sectional area is small, the heat dissipation is good, the temperature is low, etc., and the upper limit of safe current carrying is selected; However, the long distance, large cross-sectional area, poor heat dissipation, high temperature, poor natural environment, etc., the conductivity of copper braided wire is weaker, and the lower limit of safe current carrying is selected.
