Stable supply of electricity to any house or the apartment is important condition of comfortable stay in them. Correctly picked up section of wires on which current moves is one of the main factors of the solution of this task.
During electric installation work and if more precisely, at stage of laying of wires and cables, at the people wishing to make everything it is competent, there are many various questions, for example, why to sockets the cable with a section of 2.5 mm², though if to proceed from the spent power is carried out, then there are enough only 1.5 mm². The choice of necessary section of wires depends not only on spent, but also on the total total power of future direct consumers of current.
Calculation of section
Laying of electrical wiring in the house, the apartment or dachas begins with introduction cable. The main load which is available in the house is placed on it. To learn what area of cut of introduction cable is necessary, it is necessary to count the total power of all electric devices in the house. Then to increase this number by coefficient 0.75, the received result and there is size of necessary section.
Choice of wires
Further it is possible to start process of selection of cable. It is better to take wires copper, aluminum are less reliable and have the smaller term of operation. Each type of section maintains certain capacity and current intensity at which it is possible to look in the table below.
If in the house or the apartment the grounding contour is provided, it is recommended to use three-core wires if there is no grounding, also two-core will approach.
The following that should be made, it to calculate the necessary section of wires and cables for lighting and socket groups. Using this table for carrying out simple calculations, it is possible to find out that, for example, for socket groups there is quite enough wire with the section of 1.5 mm², and for groups of lighting and at all there will be enough 0.5 mm².Но, generally for lighting use wires with diameter from 1.5 mm², and for socket groups use wires which section not less than 2.5 mm² if use of the devices demanding the high power which is going beyond which the wire is capable to sustain is planned, then it is necessary to choose wider section. It is connected with the fact that wires irrespective from what metal they are made, subject to corrosion, various mechanical loadings during mounting and to permanent loads during operation. For example, using the table, it is possible to find out that at line voltage of 220B, the wire with a section of 2.5 mm² can sustain current up to 27A (5.9 kw). To protect wires and consumers, in this case the automatic machine is installed. The maximum current from which there is operation has to be no more than 25A.
It is impossible to connect among themselves aluminum and copper wires so-called "twists", they can unite only by means of the special terminals which are not allowing contact of copper with aluminum.
During process of laying of wires it is very important to take the extent of the highway which will supply the end user with energy into account. During planning and further mounting of electrical wiring, it is worth to remember also about selectivity of automatic machines. It is important to remember that electricity cannot be seen, it never forgives mistakes and the irresponsible relation to work.