Wiring diagrams in a private house: rules and design errors + nuances of electrical wiring
The wiring in the house is a whole system of wires, electrical installations and protective mechanisms, the comfort and safety of the occupants depends on the correct installation.
If the project and the wiring diagram in a private house are prepared correctly, taking into account the requirements of the IEP and other regulatory documents, there is nothing to fear: there will always be light and heat in the rooms, and electrical appliances will not break from voltage surges or short circuits in the network.
General rules for designing electrical network
When there were few electrical appliances, and several 40–60 W bulbs were enough for lighting, a primitive scheme was put in place to set up the power supply system, including several switches and sockets.
Now,with the advent of a large number of volatile household appliances, a set of protective devices is necessarily included in the circuit, and the power grid is divided into several circuits connected to individual machines.
If you consider all the nuances of the location of the wiring in a private house, taking into account the use of copper wire, it will last at least 20 years. Usually the scheme is made together with the design of a new house or before major repairs.
Begin by specifying installation locations for items such as:
- junction boxes;
- lighting devices;
- powerful household appliances;
- electrical panel
At the same stage it is necessary to decide on the way of laying the cables - open or closed. In houses with plastered walls, the closed method is usually used, with wooden - open.
Whatever scheme you use, there are a number of rules from which you cannot back down. They are spelled out in the regulatory documentation, and their effectiveness has been proven for decades.
Here are some important wiring axioms that will also be required for drawing up the scheme:
In addition to the rules, you should take into account personal comfort. For example, a double bed is usually mounted two sockets - one on each side.
The switches are located at a height of 80-90 cm from the floor. In large halls, corridors, rooms install walk-through switches.
Be sure to ground all metal sockets and objects connected to power lines. For earthing in electrical installations, the third core of the cable is used - a wire in yellow-green insulation.
Wire Selection Guidelines
In the houses of brick, aerated concrete blocks, cinder blocks required interior wall decoration, and therefore, for the laying of wires using a hidden method.
To provide additional protection, and in the case of repair to quickly replace the cable, it is placed in a corrugation - an elastic sleeve made of non-combustible polymer.
In order to choose the right cross-section of the wire, experts make calculations related to the determination of the load.
However, based on typical schemes and many years of experience, qualified electricians adhere to the following parameters:
- lighting circuits - 3 * 1.5 mm² or 3 * 2 mm²;
- outlet groups - 3 * 2.5 mm²;
- electric stove / oven - 3 * 4 mm²;
- air conditioning - 3 * 2.5 mm² (devices more powerful than 5 kW - 3 * 4 mm²);
- heating boilers - 3 * 4 mm² and more (as recommended by the manufacturer).
Cable type - three-core copper: VVGng, ShVVPng. It is impossible to use wires with a cross section less than the specified one, since they will not correspond to the load and will begin to melt, creating a dangerous situation.
Parsing wiring diagrams
Consider a few typical schemes that are used in the construction or overhaul. All options are united by the presence of a protective group: by dividing the wiring of electrics into circuits, each of which is connected to a separate machine.
Option # 1 - a general plan for the whole house
This is not a wiring diagram, but a listing of all electrical devices that are planned to be placed in the house. It is possible to calculate from it how many automata and RCDs will be required and calculate the total number of power lines leading to the shield.
Here you should specify the type of mains to choose the right cable. For a 3-phase network, take a 5-core cable, for a 1-phase - 3-core cable.
The electrical panel is located in a separate room inside the house, in the corridor, in a nearby garage. Voltage stabilizers and a back-up generator are also installed there, which supplies the house with electricity during shutdown periods of the centralized line.
For the convenience of servicing a two- or three-storey mansion, an electrical switchboard is also mounted on each floor. All switchboards are connected to the input cable - copper wire with a cross section of 15-35 mm².
If you plan to place several lamps and sockets in a separate room, then you need to mount a junction box at the entrance. It connects the input cable with a line of lighting and a socket panel.
Option # 2 - sample wiring diagram
To draw the wiring diagram, you need to take a plan of the house and designate on it the place of installation of electrical equipment.
This document becomes the basis for drawing up estimates - it is easy to count not only the number of switches, sockets and additional materials, but also to calculate the footage of the wires.
The entry point of the power line to the house and the installation site of the electrical panel is necessarily indicated.Then, on separate lines, it should be noted junction boxes, electrical installations, lighting devices.
High power devices also need to be designated, since they are powered from individual lines.
If the outbuildings are connected to the building - bath, garage, workshop - this should also be reflected in the diagram, as it is part of the wiring of electricians in a particular private house.
For schemes drawn by hand, there are no special symbols, the main thing is that the owner of the house and the installers understand what lies behind each symbol.
Option # 3 - a technical solution for a small house
All plans and schemes are similar, since they are built on the same principle, but they can differ in the number of installed outlets and lighting circuits, and therefore in the number of protective devices connected to them.
An input switch is installed in front of the network, which, if necessary, can de-energize the entire house and turn off the electricity metering device. Then the counter follows, and after it the protective groups.
For powerful units, such as a heating boiler or a washing machine, they install automatics on 25-40 A. The cross-section of wires must also be increased to 3.5-5 mm².
With this scheme, do not calculate the footage of the wires, but the number of sockets, electrical distribution boxes, switches, RCD, circuit breakers is easy to calculate.
Option # 4 - wiring diagram for basement / garage
Often, the basement of a private house becomes a utility room, where they install a washing machine and equip a dryer, a cellar for storing crops, or even a warm garage. It is much more convenient when such a room is fully equipped with sockets and lamps.
If you do not take into account the meter, on the switchboard there will remain input circuit breakers, a ground bus, a RCD of 20 A, three circuit breakers: on the lighting line, for sockets and for the compressor. Extra powerful equipment also needs automatic protection.
Option # 5 - principles of kitchen wiring
The electrics scheme for the kitchen in a private house is almost the same as for a city apartment.
Its feature is a large number of connected electrical devices, therefore, it will be necessary to allocate several power lines with separate circuit breakers.
When drawing up a vertically oriented scheme, it is necessary to display the furniture set with the arrangement of all the equipment on paper.
Straight-free connections, for example, at the oven, are made under the tabletop, near the wall, while sockets for the toaster, electric kettle, multivark, combine to carry over the desktop.
Small household appliances are easier to disconnect from the network if the wiring device is at hand. Outlets mounted near the sink must have a degree of protection against IP44 or higher.
Review of frequent design errors
Deficiencies in the scheme or planning work entail installation errors, and this threatens to disrupt the operation of the electrical grid. The result could be the failure of expensive equipment, and even worse, the electric shock of one of the tenants.
What mistakes should be avoided:
- use substandard products without labeling and certification;
- make calculations "one-in-one" - any technical products and materials must be purchased with a stock;
- put in the project the installation of conventional sockets for connecting hobs, boilers, heat guns;
- in wooden houses to plan the use of closed wiring - more complex and complying with the list of requirements of the ПУЭ;
- design switching in one junction box of low-voltage and high-power power wires;
- plan the connection of wires dangerous for further maintenance and operation of twisting; best option - ready terminals;
- make chains of aluminum and copper wires, as well as use aluminum wiring.
Some errors relate to incorrect calculations. For example, cable grooves with a closed installation method should be laid to a depth of 2-2.5 cm, not less.
Do not connect the grounding of sockets with the help of a loop, to ground to the cast-iron sewer or steel gas pipes.
If you do not know how to properly conduct electrical wiring in the house, contact the project organization. Specialists will travel to the site and draw up a wiring diagram, based on specific installation conditions.
Conclusions and useful video on the topic
Analysis of the floor plan:
Rules for drawing up wiring diagrams:
Description of the device diagram on the switchboard:
Responsibility and risks for "self-activity" in the preparation of the project fall on the shoulders of the home owner.If you do not have the appropriate education and experience, we recommend ordering documents from an organization that is engaged in professional development of electrical projects.