Wire cross-section for wiring

Electricity has become so firmly entrenched in our lives that with the sudden disconnection of electrical power our lives seem to freeze, and we look forward to it being restored. We are surrounded by a huge number of different electrical appliances that connect to the home network either directly through the sockets, or through Extension cords or carrying.

Sometimes it is necessary to light the garage or other economic building, replace the wire or make a self-made extension cord. Or you need to find out which maximum number of devices can be simultaneously included in one tee so that it does not heat the wire and cause a fire due to a short circuit. In such cases, the wire section must be calculated in advance to ensure the safety of the installed wiring.

Which wire should I choose?

It's no secret that copper has less resistance compared to aluminum, and therefore if you compare copper and aluminum wires with the same wire cross-section, then in the first case the permissible load will be somewhat larger. The copper wire is stronger, softer and does not break at the points of inflection. In addition, copper is less prone to oxidation and corrosion. The only advantage of an aluminum wire is its cost, which is three times or four times less than the copper one.

Calculation of the wire cross-section by power

Any electrical wiring must match the load connected to it. The wire cross-section is calculated based on the maximum allowable heating of the current-carrying conductor. The amount of heating depends on the power of the connected electrical appliances. Thus, by calculating the maximum possible total capacity of devices in the room, you can determine what the wire cross section should be. In practice, it is convenient to use an online calculator or special tables that contain information about the permissible current load on the cable.

How to check the wire cross section?

Since the wires most often have a circular cross-sectional shape, the shear area is calculated by the formula:

S = π х d² / 4 or S = 0,8 х d², where
S - cross-sectional area of the vein in mm.kv .;
Π - 3,14;
D is the diameter of the core in mm.

Let's assume, for example, that the wire diameter is 1.3 mm., Then S = 0.8 • 1.3² = 0.8 • 1.3 x 1.3 = 1.352 mm.kv.
If the wire consists of several wires, then the cross section of one core is counted and multiplied by their total number in the bundle. Diameter is usually measured with a caliper, but if it is not, the usual ruler will do. In this case, tightly wound a pencil about 10-15 turns, measure the length of the winding ruler and divide the obtained value by the number of turns.

With any electrical installation work, you need to remember that with electricity you can not tolerate negligent treatment and do not forgive mistakes. Electrical safety and reliability - this is what you should always strive for in any work with electrical wiring in the apartment, at the cottage or in the house.