Due to the efficiency of construction, ease of construction and environmental friendliness, many prefer wooden houses. A significant drawback of such buildings is increased fire hazard. In this regard, it is necessary to pay special attention to the issue of power supply of a wooden house. With strict adherence to the recommendations, safely and efficiently carried out wiring in a wooden house with their own hands. Step-by-step instructions will also be very useful in this matter.
Electrical installation in a wooden house with their own hands: step by step instructions
The main requirement for the supply of private homes, especially those built of wood, is safety. The installation of external and internal electrical supply systems must be performed in compliance with all rules and regulations. The documents regulating the conduct of electrical wiring are the Rules for the Design of Electrical Installations (ПУЭ), Building Norms and Rules – the section “Electrical devices”, GOST and other regulatory provisions.
In compliance with the requirements of the rules and regulations, it is possible to make the installation of electrical wiring in the house with your own hands. Step-by-step method of work includes the following steps:
- determination of the combined power of electrical equipment and the implementation of the project of power supply;
- choice of cable, electrical devices (sockets, switches), electrical appliances;
- the implementation of the input power to the house, the connection of the circuit breaker, the connection of the metering device (meter), electrical panel;
- internal cabling;
- installation of switches, sockets and lighting devices;
- device grounding system, installation of the RCD (residual current device);
- organization of preventive tests.
To start developing an individual project, it is necessary to obtain technical conditions from the electricity supplying organization (RES). They will be the basis for the work.
First of all, the total (combined) power of all electrical devices is calculated. Next step by step is developing a scheme for the electricians in the house with their own hands:
- the technical plan of the whole house building is being carried out In the scheme of electrical wiring in a private house are fixed places (points) of the location of electrical sockets, switches, lamps, as well as electrical appliances with a separate connection;
- For each electric point, the type of cable leading to them is selected. If two-button switches and grounding sockets are used, a three-core cable is connected to them;
- on the wiring diagram of the wiring in a wooden house indicate the installation location of junction boxes. It is recommended for two adjacent rooms to use one box;
- on the wiring diagram of the wiring in a private house reflects the power of each device. If the device has an electric motor, the value is indicated taking into account the starting power of the electric motor;
- all lighting devices (chandeliers, wall lamps, etc.) are connected to one group, and more powerful appliances (boilers, boilers, electric furnaces, etc.) are combined into another group. For them, the cable is supposed to be connected and connected through a separate automat;
- the diagram indicates the distance from the cable run to the doorway, windows, and the distance from the electrical points to the floor and ceiling. In the future, this will help avoid damage to electrical wiring during repairs.
Helpful advice! All turns of the internal wiring cable must be performed exclusively at an angle of 90 degrees.
After that, the calculation of the maximum power consumed by all electrical devices when they are simultaneously turned on. Determine the nominal load on the input (first along the power supply) machine.
In order to properly conduct wiring in a private house with your own hands, avoiding complicated special calculations, you can use the “Table of the ratio of cable cross-section to the corresponding load” from the electrical reference book.
From the table, select a cross-section of cable that will match the power of electrical appliances for each individual group. Each device is accompanied by a description or a technical passport, which indicates the load it consumes. Based on this data, choose an acceptable cable. In order to determine the cross-section of the input cable, sum up the power of all available devices.
The most popular cable for wiring is NYM copper cable. It has extra insulation, is sturdy and easy to handle. In the case of aluminum cable, it must be borne in mind that it is vulnerable to bends and often breaks during cutting.
A three-core wire with grounding is supplied to the sockets to ensure the safety of household electrical equipment. Lighting devices, in accordance with the Rules for electrical installation, also need to be refurbished, although many people ignore this norm. If in a private house is used to illuminate the territory of the yard and the plot powerful spotlights, the organization of grounding is a prerequisite. This rule applies to those who decide to do their own wiring diagram at the cottage.
Sockets and switches are selected based on the calculated current value, type of electrical wiring (hidden or open), the possibility of connecting the unit with a socket and a switch under the same frame.
By calculating the nominal load of all intended to install electrical appliances, determine the cross-section of the input cable. For those cases when the electrical wiring is updated with the replacement of internal wires and circuit breakers with more powerful ones, do not forget about the cable at the input. It may happen that its cross-section will not be enough for too much power – this can provoke a fire. Therefore it is necessary to contact the appropriate organization for the replacement of the input cable. This can be done at the installation stage of the metering device and its sealing.
As for the input circuit breaker, a three-pole circuit breaker is used for a three-phase power supply. If the power is single-phase, which occurs in 90% of cases, use a single-or two-pole circuit breaker, breaking the phase and neutral.
Helpful advice! An introductory circuit breaker is selected with such a rating that it does not shut off the power at home at maximum load, but breaks the circuit to prevent a short circuit.
The circuit breaker is selected based on the following:
- determine the sum of the power of all electrical equipment and calculate the value of the maximum current using the formula: Ihom = P / U x cos ?. What is cos? take 0.8. A correction factor of 1.1 is applied to the obtained value of the rated current Ihom. As a result, the maximum current is obtained at which the automaton operates. A 25 A circuit breaker is usually enough to enter the house;
- to determine the type of machine, you should know the minimum value of short circuit current. The formula for determining the current in a single-phase network (220 V) is as follows: Ikz = 3260 x S / L, where S is the cable section, (mm?); L – cable length, (m). This formula determines the current for the longest section with the smallest wire cross section;
- the ratio of the magnitude of the short circuit current to the value of the rated current determines the characteristics of the circuit breaker. The recommended automatic device for installation in a house is a switch with characteristic C. Such an automatic device works perfectly in networks with mixed loads.
According to the wiring diagram in the private house with their own hands set the introductory machine after the metering device. Circuit breakers for united in one group of devices, metering device, input circuit breaker and RCD are mounted on a special metal profile (din-rail) in the switchboard. Next, make the wiring according to the wiring diagram of the wiring in a private house.
The installation of electrical wiring begins as soon as all necessary devices are acquired: cable, sockets, switches, breakers, lighting devices.
According to the existing scheme, junction boxes are mounted, fixing points for fixing sockets, switches and lighting devices. If indoors all walls will be sewn up with finishing material, the cable is laid in a metal sleeve.
The body of the electrical panel is fixed in the place established by the scheme. Then do the following:
- the metering device is mounted in the housing of the shield;
- An introductory automat is installed on a special metal profile (din-rail). Phase and neutral are fed to the bipolar automat;
- output terminals (terminals) of the metering device are connected to the input of the input circuit breaker;
- the wire is brought into the house and connected to the input terminals of the metering device (meter);
- din-rail mounted voltage relays, machines for different power groups (sockets, lighting), RCD;
- electrical appliance clips are connected with a single cable.
The input of the power cable to the wooden house must be carried out in accordance with the PES and SNiP.
The input cable can be brought into the room by air or underground. It should be noted that the air method is less expensive, but not entirely reliable. In such cases, use self-supporting insulated wire (CIP). In the case of air entry, it is imperative that a non-combustible liner be installed in the wall through which the entry will take place.
The underground wire is laid underground in a metal pipe that protects it from all kinds of influences. Such cable laying is necessarily coordinated with the distributing power company.
If the project provides for open wiring, there are several ways to install it:
- Ceramic rollers for open wiring – this method is convenient for laying wires on a wall of logs. It will be appropriate in the retro interior;
- metal pipes – this method reliably protects housing from fire. Pipes should be filled with wire not more than 40%. It is recommended to use copper wire that bends easily;
- cable channels made of plastic – the channels are attached to the wall, you can choose plastic channels of different colors to match the finish of the walls;
- plinth with a special channel (chute) – with this method, clamps are installed in the plinth channels for fastening the wire;
- fastening with clips – plastic clips are selected according to the size of the wire section. This method is most often used for wiring in utility rooms due to unattractive appearance.
Helpful advice! All passages of the electric wire from room to room through the wall must be equipped with metal fireproof sleeves, through which the cable is pulled.
In some cases, the cable is laid under the floor of the boards using metal pipes.
It is possible with the help of cable channels to mount electrical wiring in a wooden house with your own hands. Step by step instructions for laying wires in the cable channel:
- mark up the line of passage of the wire, according to the existing scheme;
- the cross section of the cable channel depends on the number of wires placed in it;
- remove the box cover and fasten it with screws to the wall or ceiling. Screws have an interval of half a meter. Turning places are additionally reinforced with self-tapping screws;
- junction boxes are installed in the established places;
- the necessary wires are laid in the cable channels and snap-on the lid. In places where the sockets and switches are connected, a margin of wire is left to connect them;
- connect all the wires in the junction boxes, connect to the terminals of circuit breakers, switches and sockets.
Installation stages can be seen on various photos of electrical wiring in a wooden house.
The rules provide for the connection of wires inside the wiring box. Boxes are installed in places where there will be bends from the main cable. The wires are connected by such methods:
- the connection can be made using self-clamping terminals (Wago). With this method, it is sufficient to remove 10 mm of insulation from the wire. Terminals are selected according to the size of the cross section of the wire together with an insulating coating;
- You can connect the wires with insulating caps for twisting. With this method, the insulation is removed from the wire so that the length of the bare segment does not exceed the length of the cap. Inside it has a conical spring. When the cap is wound on a twist – the spring firmly clamps the wire, and the plastic sheath provides insulation;
- Twisting involves cleaning the wires from the insulating coating by 4 cm and tight twisting. All stranding is recommended to be soldered and wrapped with insulating tape.
Helpful advice! The number of wire connections in the network affects the ability of the system to transfer loads: the more connections, the lower the load capacity.
When connecting wires, it is necessary to consider the color of the insulation. Red, brown color of insulation – wires with a phase, blue, white – neutral (zero), yellow, greenish – ground wire.
Modern home appliances home appliances can not do without such appliances as a boiler, washing machine, refrigerator and many others. The presence of electrical equipment with a metal casing implies a mandatory grounding device.
The order of the grounding device is as follows:
- three reinforcement rods 3 m long and 3 cm in diameter are prepared. A trench in the shape of an equilateral triangle with a side length of 1 m is excavated. A trench depth is 30 cm. The armature is placed in the ground at the corners of the resulting triangle;
- reinforcement rods are interconnected by a metal angle with the help of welding;
- A loop (eye) is welded to one of the corners and a rod made of steel 1 cm thick is attached by means of a screw connection or by welding.
- the rod is laid in a trench in such a way as to connect it to the grounding conductor in the electrical panel. Grounding cables have yellow-green insulation.
To protect a person from electric current when it leaks onto the body of electrical equipment, a protective shutdown device (RCD) is used. This device is mounted in the shield after the metering device. Based on the magnitude of the nominal current in the network, they select the parameters of the RCD that reacts to the slightest leakage of current. The presence of such a device is especially important for rooms with high humidity.