1. What is the square number of wires? How to calculate the number of squares of cables?
The number of squares is a nominal value stipulated by the national standard, and the number of squares is for the user to choose the wire and cable according to the load of the wire and cable.
The number of squares of wires is an oral term in decoration and hydropower construction. The number of squares of wires that is often said is without units, that is, square millimeters.
The square of the wire actually refers to the cross-sectional area of the wire, that is, the area of the circular cross-section of the wire, in square millimeters.
Generally speaking, the empirical load capacity is about one kilowatt per square wire when the grid voltage is 220V.
Each square of copper wire can carry 1-1.5 kilowatts of electricity, and each square of aluminum wire can carry 0.6-1 kilowatts of electricity. Therefore, an appliance with a power of 1 kilowatt only needs to use one square copper wire.
As for the current, in short-distance power transmission, the copper wire can carry 3A to 5A of current per square. The heat dissipation condition is good to take 5A/square millimeter, and it is not good to take 3A/square millimeter.
2. Conversion method:
Knowing the square of the wire, calculate the radius of the wire using the formula for the area of the circle:
The number of squares of wires (mm2) = Pi (3.14) × the square of the radius of wires (mm)
Knowing the square of the wire, the same is true for calculating the wire diameter, such as:
The wire diameter of the 2.5 square wire is: 2.5 ÷ 3.14 = 0.8, and then the square root is 0.9 mm, so the wire diameter of the 2.5 square wire is: 2 × 0.9 mm = 1.8 mm.
Knowing the diameter of the wire, calculating the square of the wire is also calculated using the formula for the area of the circle:
The square of the wire = pi (3.14) × the square of the wire diameter / 4
The size of the cable is also nominally squared, and the multi-strand wire is the sum of the cross-sectional areas of each wire.
Calculation formula of wire cross-sectional area:
0.7854 × wire radius (mm) square × number of strands
Such as 48 strands (radius of each wire 0.2 mm) 1.5 square wire:
0.7854 × (0.2 × 0.2) × 48 = 1.5 square