Instructions for calculating suitable cable diameter for use capacity.

tính toán chọn tiết diện dây dẫn phù hợp

Our country is developing very fast according to the trend of the era, the demand for housing is increasing with the development and urbanization.

Currently, investment in new construction and upgrading of housing infrastructure is increasing.

The development and upgrading of electrical systems in buildings, large and civil systems is necessary to increase according to practical needs.

However, ensuring proper technical standards and safety for electricity use and saving investment costs is a problem that many people care about.

In the electrical system, the leveling is very important.

Calculating cable diameter is very much interested, not only because of safety, saving investment costs but also reducing power loss transmission, saving power for users as well as electricity industry.
“Calculate cable Diameter” is an indispensable requirement

If using a wire with a cross section less than the permitted level, the following phenomenon will happen.

The wire is always in overload

Hot wire

Prolonged use will lead to brittle wires

Melting insulation causes breakage

Short circuit, burnt wiring, causing damage on large lines.

Hướng dẫn tính toán chọn tiết diện dây

If the cross section of wire is too large, it will cause waste of investment, the construction process will be affected much to the art of the house.

Some Tips for selecting the cross section of wire.

– Selecting cross section of wire according to calculation formula

– Selecting the cross section of wire according to the standard

– Selecting the cross section of wire according to user experience

For residential electricity, it is possible to apply simple options as follows:

– Cable cross section select 6A / 1mm2

– Calculate the total power used (including room for later expansion) before selecting for the total power supply cord.

– It is recommended to use 70% of the rated capacity (eg 1mm2 withstand 6A line, we only use equipment with a capacity of 4A).

For 220V household electricity, choose the following.

The total capacity of household appliances is 5kW (theory published by the manufacturer), we calculate the following:

– Total current It = P / U = 5000/220 = 22.7A

– Then choose wire cross section of S = 22.7 / 6 = 3.78mm2

– We should choose the wire diameter of 4mm2

-To ensure redundancy (according to each use request) we choose S=1.75×3.78=6.615mm2.

So we should choose the wire with cross section of 6mm2 to reserve the capacity to add load (at the allowable level for each house) as the main power supply cord.

For power supply line branching to each floor, indoor room depending on the level of layout of electrical appliances, we choose as follows: split load by floor, choose 4mm2 wire, supply power to the socket, choose the  2.5mm2 wire, lighting wire select 1-1.5mm2

In order to be calculated correctly, you should calculate the power details before choosing to ensure the most optimal.

Hao Phuong is currently an importer and distributor of industrial electrical equipment with major brands in the world such as IDEC, FUJI ELECTRIC, TOGI, KANSAI, NICHIFU, CIRCUTOR, HONEYWELL, TAIWAN METTERS, Bin Master, … at the same time, Hao Phuong was also the leading industrial system integrator in Vietnam.