Types of the electrical wiring and ways of input of the cable
Today such important issues as input of the electric power to the building and main types of the electrical wiring indoors will be considered.
Ways of input of the electric power to the building
Input from the air power transmission line
Inputs from the air power transmission lines to buildings are divided into two sites:
- 1. The branch from the air-line before input is the site of wires from the support (column) before input to the building.
- 2. Input to the building – the site from insulators of the outside wall of the building to the input device which is in this or that room.
The branch from the air-line before input in the structure and also intra domestic networks should be carried out insulated conductors or the cable laid on the trosovka or in the earth. Section of wires in the branch has to be not less than 6 mm ² for copper and not less than 16 mm ² for aluminum. Section of cable cores – not less than 4 mm ² for aluminum and 2,5 mm ² – for copper.
The distance from branch wires to the earth has to be not less than 6 m in the carriageway, and in the yards – not less than 3,5 m.
Distance from the earth to the insulator of input to the building – not less than 2,75 m. Wires of the outside electrical wiring always have so that they were unavailable to accidental touch.
The wires laid openly on walls have to be at the following distances:
- over the balcony, the porch – 2,5 m;
- over the window – 0,5 m;
- under the window – 1 m;
- under the balcony – 1 m, is horizontal laying.
At vertical laying to the window – 0,75 m, to the balcony – 1 m.
At the suspender of wires on support about buildings the distance from wires to balconies and windows has to be not less than 1,5 m.
Inputs to the building are carried out always only by insulated conductors. Each wire is concluded in separate rubber isolation. In the building plugs are put on tubes. Openings in the wall it is surely closed up. Passes through walls in tubes are carried out with the bias outside that water could not get in the room. After laying of the opening are closed up by water-proof solution. Input in the structure is carried out by the cable in the nonflammable cover, with a section not less than 4 mm ² for aluminum and 2,5 mm ² for copper or insulated conductors of the same sections.
Input of the cable to the building the pole
Input by the pole through the wall is more convenient. Here it is always necessary to watch that the lower horizontal end of the pipe was with the bias 5 ° outside, and in the lower point of the pole the opening with a diameter of 5-10 mm for the moisture exit is surely drilled.
Also there is the input the pole through the roof. It is applied if the distance from the Earth's surface to the bottom of the pole established on the wall will be less than 2 m.
Input of the cable to the building the subway
From the support to the building wall the cable is laid in the trench which depth has to be not less than 0,7 m. The branch from the air-line is carried out the cable. In this case the cable is laid on the support before its soft junction in previously dug trench. From accidental damages the cable on the support is protected the pipe or any other design on height to 2 m.
In the base of the building the opening for input makes the way. Input is always carried out in the pipe. The pipe is selected more than diameter of the cable with a diameter at 2-5 mm. Pipes keep within with the bias outside to exclude hit of moisture to the room. Depth not less than 0,5 m. From the inside of the building the pipe has to act on 50 mm, and with outside on 600 mm from the base.
At input to the building in the trench the small stock of the cable on any unexpected situations is always left. In one pipe one cable is laid. If it is necessary to enter several cables into the building, then the distance between pipes has to be not less than 10 cm, and from the base if pipes are laid lengthways, not less than 0,6 m.
In apartment houses the feeding cable is entered into the input box which is connected by the crossing point to the distribution board. Struts which are laid vertically on mines in walls depart from it. Floor boards from which wires already disperse on apartments are attached to struts on each floor.
Distribution of electricity between apartments and all-house loadings – rather difficult thing. Distribution in this case is carried out by means of electrotechnical devices. Their amount, installation sites and ways of fastening have to be strictly agreed with the structure of the house.
Input of cables to buildings is quite difficult and responsible process where it is impossible to neglect all established rules that then there were no problems.
Types of the electrical wiring in the apartment and the house
Before beginning electric installation work, it is necessary to decide in what way you will lay the electrical wiring.
There are three main ways:
- Buried electrical wiring.
- Open electrical wiring.
- Electrical wiring in electrotechnical products.
When mounting wiring in all cases it is necessary to follow the following rules:
- horizontal wires have to go strictly horizontally,
- vertical – vertically.
The buried electrical wiring – at this way of the wire pass in flexible tubes (corrugation) or bury in walls. The buried wiring is done in not trimmed rooms, that is before plaster works. In rooms which are plastered for laying of wires or the cable it is necessary to do shtroba.
At the shtrobleniye it is necessary to consider the following requirements:
- shtroba should not reduce wall durability,
- the shtrobleniye within the walls of flues is inadmissible.
At the shtrobleniye of channels it is possible to use shtroborezy or the Bulgarian. Performing this work, it is necessary to consider depth of the canal as you should lay to it to the corrugation (if the wire keeps within in special the corrugation for the hidden electroconductings) and then to close up all this solution that the place of laying of the wire was aflush with the wall.
Telephone cables cannot be carried out in one corrugation with power. The distance between them has to be not less than 10 cm.
The open electrical wiring is mounted more simply, causes at the same time smaller damage of walls. There are several options of mounting of the open electrical wiring.
The 1st way is the fastening of wires directly to the wall. This way can be chosen at insignificant expansion of the electrical wiring, but here it is necessary to consider that with the electrical wiring of this kind there was no direct contact or accidental touch.
The 2nd way is the electrical wiring in rigid plastic pipes. In this case electrical wires place in rigid plastic pipes which fasten to walls by means of special support.
Council: do not use the old or recovered pipes.
The table of the applied insulating pipes which are used for the hidden and open laying of the electrical wiring is included below. Marking of pipes always is on the surface and contains all necessary data. How to decipher designations in the provided table?
The first letter of marking can be the I (insulating), M (mechanical), With (composite).
The second letter (and also the third if marking contains four letters) can be R (rigid), With (bending), T (elastic in transverse direction), S (flexible).
The third letter designates appearance of the pipe: And (corrugated), L (smooth).
The series from four digits after three or four letters designates one after another compressive resistance, resistance to blows, minimum temperature of use and maximum temperature of use.
The 3rd type of the electrical wiring is the electrical wiring in electrotechnical products. Are meant by electrotechnical products the box and the plinth.
The table of the most often applied materials.
At the choice of the electrical wiring it is also necessary to consider in what room it will be carried out.
All rooms are divided into the following categories:
Dry call rooms in which relative air humidity does not exceed 60%.
Dry rooms are called normal if there are no conditions especially crude, hot, dusty.
Wet are those rooms in which relative air humidity more than 60%, but does not exceed 75%. Vapors or the condensing moisture in them are emitted temporarily and in small amounts.
Rooms belong to crude. in which air humidity the long time exceeds 75%.
Besides, rooms are divided into the following types on fire danger degree:
- normal rooms;
- rooms with the increased danger;
- especially dangerous rooms.
And, respectively, wires approach all this. The table is included below:Top