These are works on the replacement or repair of electrical network elements: lamps, sockets, switches, etc., which are carried out without changing the unified scheme, as well as work on the complete or partial replacement of the electrical network, which are carried out with changes to the unified scheme.
To carry out work of the first type, it is not required to draw up a new electrical work project. During their implementation, it is necessary to strictly observe safety precautions in order to avoid possible accidents.
Before starting the repair or replacement of individual electrical elements, it is necessary to turn off the machine located in the electrical panel in order to de-energize the wires. It is advisable to additionally check the wires for the absence of current using a special indicator screwdriver. The indicator, in contact with the wire, shows whether there is a phase on it or it is absent.
Very often in modern country houses there are problems with electrical wiring due to its overload. Today, even a seasonal home is equipped with a variety of powerful household appliances: an electric kettle, air conditioning, a washing machine, an electric oven with an air grill, etc. In this case, the craftsmen offer to make a complete replacement of the electrical wiring. But, firstly, it will require significant financial costs, and secondly, to lay new lines, it will be necessary to ditch the walls. Consequently, after the completion of electrical work, repairs will be required in all rooms, which is far from always desirable.
Of course, a complete replacement of the electrical wiring is ideal, but it is not suitable for every family. Therefore, in this case, it is worth giving preference to a partial change of wiring.
Since the main consumers of electrical energy in modern homes are washing machines, split systems and kitchen appliances, it is enough to extend new lines for them to solve problems with electrical wiring. An operation of this kind is carried out quickly and causes minimal damage to the appearance of the home. After all, with a partial replacement of electrical wiring, the cable is laid externally. The route for such a laying is chosen so that the lines laid in the cable channel are hidden by decorative elements and are almost invisible to the eye.
In the production of a partial replacement of the electrical wiring, any part of the dwelling is chosen, where the old wiring is turned off and a new one is laid, which will best meet the requirements of the people living in the country house. All new electrical wiring is brought into junction boxes. They are temporarily connected to the cable that feeds the old wiring.
After that, the replacement of electrical wiring is carried out in other rooms. Then the new wiring is connected to each other in junction boxes, after which it is connected to the electrical panel.
Disadvantages of Partial Rewiring
When choosing a partial replacement of electrical wiring, laying wires in one of the rooms, you will need to power the new fixtures and sockets from the old existing junction box. It should be recalled that the old electrical wiring was usually aluminum wires. If they are directly connected to new copper wires, electrochemical incompatibility will occur, which is unacceptable.
Of course, for this purpose, you can purchase special connecting terminals, which are presented on the modern electrical market in a wide range. But you should take into account all the possible difficulties associated with their use.
In addition, there may simply not be free space in the junction box for new connections, or there may be so many old connections that brittle aluminum wires will need to be reconnected.
There will also be certain difficulties with the uniform distribution of the load and the compliance with it of the cross section of the electrical wires in the wiring. If, for example, you replace the old wiring in one of the rooms, increasing the total number of “points” in it and connecting the new wiring to an existing junction box, there will be a current overload of those wires that feed this box.
If the electricity suddenly cuts off in the house, you must immediately disconnect all high-power electrical appliances from the sockets, since when the power is turned on suddenly, the inrush currents of the devices can overload the power grid and cause damage to it. Starting currents are available in every electrical equipment. For example, the current in an incandescent lamp exceeds its nominal value by 3-4 times.
The thing is that the old wiring in almost all houses is made with only one power supply group of aluminum wires, the cross section of which does not correspond to the significant power consumption, as well as the number of modern household appliances.
In this case, it is desirable to power the room by bypassing the junction box. To do this, it must be connected directly to the circuit breaker in the switchboard.
But even such a solution cannot be called universal, since the wires laid to the electrical panel through the whole house (even hidden in the cable channel) are unlikely to decorate the home. And if it is not planned to carry out repairs in the house, it will not work to hide the wiring in the strobes.
Thus, the disadvantages of partial replacement of electrical wiring include:
- an increase in electrical wiring switching points, which in the future may become a potential source of problems;
- an increase in the number of consumables, since all cables will need to be brought into junction boxes, and when completely replaced, they go directly to the electrical panel;
- increasing labor costs and, consequently, the cost of replacing electrical wiring in general.
Before embarking on a partial replacement of electrical wiring, you should stock up on tools. To perform such work, you will need screwdrivers, a puncher, a grinder, a soldering iron, terminal blocks, pliers, a knife, a building level, a spatula, and a phase indicator.
Rewiring must be carried out in such a way that overvoltage does not occur in the network and failures do not occur. Therefore, each device included in the network must have enough power.
Power directly depends on the cable cross-section. In order not to make a mistake with the choice, you should make a small calculation. First, add up the power of all household appliances that are planned to be included in the network. After that, for each electrical appliance, it is necessary to add an additional 100 W, the number obtained as a result of the calculations, divided by 220.
If the final number is in the range of 12-15, then wiring with a cross section of 1.5 mm 2 will be enough to provide all devices with sufficient power. This indicator is the most common. But in some cases the result is better. There are two options for solving the problem: lay wiring of a larger cross section or draw 2-3 cable lines from the electrical panel. The second option is preferable, since thicker wiring will make the entire system not very reliable and, as a result, the probability of failures will be high.
Partial replacement of electrical wiring is carried out in several stages. First, the dwelling is de-energized, then it is checked again that the current is really no longer flowing.
After that, replace the wiring in the selected room and connect it to the junction box using terminal blocks. Or, as mentioned above, they feed the new wiring bypassing the junction box, laying the wires directly to the electrical panel.
When all the wires are already connected, they are hidden in decorative boxes. Lastly, sockets and switches are mounted.
Selection of the wire section for the replacement of electrical wiring
If, for example, the total power of all household appliances used in the house connected to one outlet is about 6 kW, and the total power of all lamps connected to the same line is no more than 4 kW, then when replacing electrical wiring in certain areas, it will be necessary to use copper wires of the following markings:
- for lines leading to sockets - non-combustible VVGng wire with insulation and vinyl sheath with a cross section of 3 x 2.5 mm 2;
- to replace lighting wiring - VVGng wire with a cross section of 3 x 1.5 mm 2;
- to replace the electrical wiring used to connect the water heater to the network - connecting wire PVA with a sheath made of vinyl or VVGng with a cross section of 3 x 4 mm 2;
- to replace the electric line that feeds the electric stove - PVA wire with a cross section of 3x6 mm 2;
- to replace the input line to the house, copper wires with a cross section of 3 x 10 mm 2 will be required, since only such a wire can withstand the maximum current strength.
The quality of the wiring is largely dependent on the quality of the switches and sockets. It is in these devices that overheating and fire can occur, and you can also get an electric shock from them. It is easy to check the quality of the outlet, for this you just need to insert the euro plug into it. If it is securely fixed in the outlet, then the device is of high quality. The plug will fall out of a bad outlet.
Need to know for the correct partial replacement of electrical wiring
- All old wires must be replaced only with three-core electrical cables made of copper, having a cross section of 1.5 mm 2, if the maximum planned connected power to one machine is no more than 3.2 kW, or 2.5 mm 2, if the maximum power does not exceed 5 kw. For powerful household appliances, such as an air conditioner or a washing machine, it is advisable to lay a separate line that connects to the electrical panel.
- For laying under plaster, a VVG 3 x 1.5 cable is used, in pipes - an insulated cable of the VVGng brand 3 x 1.5. If the wire is laid openly along the ceiling and walls (for example, it will be hidden behind a false ceiling), use the VVG ng LS 3 x 1.5 cable. It does not burn, and also does not smoke under the influence of a flame.
- If electrical units or sockets are nearby, then you can power them one from the other. But it is not recommended to connect more than three nearby blocks in this way.
- It is permissible to work only in a completely de-energized area. Before proceeding with the replacement of wiring, it is imperative to check whether there is voltage in the network or if it is absent.
- The covers of the junction boxes are always left in sight and in an accessible place, the wire connections are made using PPE or terminal blocks. If the soldering boxes are planned to be hidden behind the wall decoration, then all the twists are welded or soldered. The twists of zero, phases and earth are bred in different directions.
- Modern electrical wiring can only be three-wire, it must have an additional ground wire. Therefore, sockets must also have grounding contacts. Electrical enclosures of chandeliers and other fixtures are also subject to grounding.
- Thanks to the installation of a difavgomat or a residual current device, it is possible to completely eliminate the possibility of electric shock to a person. Since aluminum and copper wires, in contact with each other, oxidize very quickly, as a result of which the contact disappears, it is permissible to connect them only using terminal blocks.
- The cables going to the switch, chandelier and lamp must be signed, this will allow the box to be disconnected much faster in the future.
- When wiring in the bathroom, certain rules and regulations must be observed. Since air humidity is often increased in this room, condensation forms on the walls, and wet walls and wet floors conduct electricity perfectly. This greatly increases the likelihood and severity of electrical injury.
Previously, electrical switches and sockets were not installed in this room at all. The bath was only illuminated by a lamp located on the ceiling.
Today the situation has changed. Fans, boilers, shower cabins, Jacuzzi, etc. are installed in the bathroom, so it is impossible to do without electricity in this room.
Before you start wiring electrical wiring, you should finally decide on the installation location in the bathroom of switches, sockets, lamps. Also, such work is carried out only after the cable is directly connected to the terminal blocks of the household electrical appliance.
All electrical switches, sockets, as well as lamps and other household appliances installed in the bathroom must be reliably grounded and have a moisture protection class of at least IP 44. Any connection or lighting control points must be located at a distance of at least 60 cm from bathtub or shower. Closer, you can only equip the backlight for the jacuzzi, since it has a power of up to 12 watts.
It is forbidden to mount sockets near the floor, otherwise, if water leaks, they will inevitably get wet.
Rules for installing electrical wiring in the bathroom
All elements made of metal require reliable grounding. In new houses, a potential equalization system is always equipped. It consists of a terminal box to which wires are connected to all metal metal elements in the bathroom.
Never use household electrical appliances while standing on a damp floor or in water, as this may result in electric shock. Also, in no case should water be allowed to come into contact with household appliances connected to the electrical network.
The wire from the PE ground bus of the electrical panel, as well as the wire from the strip running along the riser, fits into the terminal box.
It is welded to the ground loop in the basement.
The junction box in which the wires are connected is equipped near the bathroom.
Inside the premises it is unacceptable to make twists and other connections. Any connections can only be made using a single piece of cable extending from the terminal box.
When arranging the wiring, a cable made of copper VVGng 3 x 1.5 is used, which is non-combustible, or VVGng-LS, characterized by a low level of smoke generation.
It is permissible to use only three-core cables for connecting luminaires. In old country houses with two-wire electrical wiring, you will need to run a third ground wire from the electrical panel.
The power cable in the shield must be connected either to a difavtomat or to a two-pole residual current device. They provide an instant shutdown of electrical energy in the event of a current leakage, as a result of which the likelihood of injury is reduced to zero.
Electric cables in the bathroom are laid only in a hidden way, for which strobes are made, then the cable is securely hidden under tiles or plaster. True, it is allowed to lay cables openly along the ceiling and walls, but in this case they must be hidden in corrugated PVC pipes.
If you decide to repair in your place of permanent residence, then replacing the old wiring in the apartment should be a must for you. After all, the houses that were built back in Soviet times were not designed for modern loads.
Therefore, if, having completed the repair, you did not pay due attention to the wiring, this can become a serious headache in the future.
Choice of wiring options
The selected version of the wiring diagram for the apartment largely depends on the method of laying it that you have chosen. At the moment, there are two main types - this is an open and hidden method. The hidden method of laying electrical wiring involves laying the wire inside the walls, followed by their plastering.
The advantages of this method include:
- Saving free space in the apartment
- Complete concealment of all current-carrying parts that do not spoil the appearance of your room
- No need for additional protection of wires from mechanical damage
- Higher load and overload tolerances for any concealed wires
The disadvantages of the hidden wiring method include the following parameters:
- The complexity and laboriousness of the work on laying the wire
- Difficulty in identifying faults and repairing hidden wiring
The second way to replace the wiring is the open method. Conventionally, it can be divided into laying wiring in skirting boards and laying in cable ducts.
Of course, there are still other methods of laying open wiring, but they are used very rarely in apartments due to their ugliness.
The advantages of replacing electrical wiring with your own hands in an open way include:
- Relative ease of installation
- Easily locate faults and repair wiring
- Ease of additional wiring for new power sources, as well as making changes to the apartment's power supply scheme
But there are a lot of disadvantages of the open wiring method:
- Hiding the free space of our already small apartments. When installing furniture, additional boxes can greatly interfere
- If the baseboard wiring method is used, the number of possible wires is very limited. This introduces significant restrictions on the options for choosing a power supply scheme.
- Wires when laid in an open way require additional protection against mechanical damage and its isolation from each other and from combustible surfaces for fire safety purposes. Because of this, the price of such wiring is somewhat higher.
- For open wiring, the parameters of the maximum allowable load and overload are slightly lower due to their poorer cooling.
Choosing an apartment power supply scheme
At the next stage, replacing the wiring in the apartment involves choosing a power supply scheme.
There are currently two main options:
- The first, which was probably used in your Soviet-built house, is the laying of one main wire from which all the wires of the apartment's electrical receivers depart. This method does not provide adequate protection for the electrical network of your apartment. Indeed, in the event of damage to even one section, your entire apartment will be de-energized.
- It should also be noted that according to paragraph 6.2.2 of the "Electrical Installation Rules" (PUE), group indoor lighting networks must be equipped with a circuit breaker of no more than 25 A. This introduces certain restrictions on the total power of electrical appliances in the apartment.
Therefore, such a wiring diagram is advised to be used only for one-room apartments or with an open method of laying wires in baseboards. After all, it will be extremely problematic to lay a large number of wires in the baseboards for powering according to a different scheme. - More common now is the so-called "European" power supply scheme. It implies the presence of a switchboard and the presence of circuit breakers for each individual consumer.
It can be one room or one type of consumer in the room. It all depends on the expected load, your wishes for the safety of the power grid and your financial capabilities.
Sometimes you can find the use of mixed wiring diagrams. This is a rather rare case, but it also has the right to exist. It all depends on the nature and type of loads.
Calculation of electrical wiring
Since it is impossible to replace the electrical wiring in a panel house apartment or any other place without an accurate calculation, at the next stage we proceed to the calculations.
Attention: First of all, we need to determine the possible loads on each section of the electrical network protected by a circuit breaker. Based on these loads, not only the wire is selected, but also the circuit breaker itself.
So:
- To determine the load, we use the formula; where P is the rated power of the appliance, and U is the rated voltage of the electrical network. Based on this formula, for a 220V network, it can be assumed that 1 kW of power of electrical appliances is 5 A of load for the wire.
In this case, it can be simplified to accept that a copper wire with a cross section of 1 cm 2 passes a current of 10A, and an aluminum wire with the same cross section - 5A. This is, of course, a very simplified calculation, but in most cases it is sufficient.
Let's pay attention! For an accurate calculation of the required wire cross-section, use paragraph 1.3 of the PUE. Here you will find correction factors depending on laying conditions, laying methods, number and cross-section of wires laid side by side, temperature and overload correction factors, as well as design parameters for wires with different insulation structures.
- We will immediately warn you from the most common mistakes. First of all, please note that the cross section of the wire of one of the connections cannot be larger than the cross section of the input wire. Circuit breakers must comply with the maximum permissible connection current.
Note! When calculating, you should not take into account the operation of all electrical appliances at once, otherwise this will lead to a significant increase in the cost of your electrical network. Remember, any electrical wires allow short-term overload up to 10 - 15% for 1 hour per day.
Replacing the electrical wiring in the apartment is carried out only in compliance with the norms of the PUE and elementary rules. It is quite difficult to list all of them, so below we will only list the most common mistakes made by non-professionals, which can lead to problems during operation.
So:
- It is forbidden to install circuit breakers and fuses in zero working and grounding conductors.
- The wiring of the 220V network must be carried out with a three-phase wire, where 1 wire is phase, 1 wire is neutral and 1 wire is ground.
- According to clause 7.1.37 of the PUE, the installation of sockets in bathrooms and shower rooms, as well as baths, is not allowed. And, according to clause 7.1.39, it is forbidden to install switches in these rooms.
- The connection of wires must be made by soldering, crimping, welding or bolting.
- In the places where the wires are connected, it is necessary to provide a margin that ensures reconnection.
- Metal wiring elements (boxes, trays, corrugated hoses) must be grounded.
In addition, the replacement of electrical wiring in an apartment implies compliance with elementary rules:
- Wiring must be carried out strictly vertically or horizontally. Otherwise, the likelihood of subsequent damage to the wire increases dramatically.
- Switches and sockets should be located at the same height.
- Avoid crossing wires.
- Do not place sockets and wiring too close to heating equipment and water supply systems.
conclusions
Our simple instructions for carrying out work on replacing electrical wiring will allow you to perform work in full compliance with the requirements of the PUE. At the same time, having made the right choice of the scheme and method of laying the wire, you will surely be able to cope with all the work in the shortest possible time and at minimal cost.
This is due to material possibilities, as well as the specifics of the repair. For example, if the owner of the apartment decided to make repairs only in the bathroom and in the kitchen, there is not always a desire to change all the wiring in the rooms. However, leaving the old electrical wiring in the rooms where the renovation will be done is not the right solution. It is better to overpay a little and replace the cable, as well as electrical accessories with a new, safer and better one. In this case, just a partial replacement of wiring in an apartment or a private house is applied. Features of the work, as well as the advantages and disadvantages of this method will be outlined below.
Is it worth it to change the wiring in parts
To make it clear, it is rational to change the electrician in parts and whether it is possible to do this at all, first we list the advantages of this type of wiring:
- Lower costs.
- The speed of wiring several rooms (or individual lines) is higher than a complete rewiring.
- There is no need to make repairs in all rooms.
On this, the advantages of partial replacement of electrical wiring end. If we talk about the shortcomings, there are many more:
- it is possible by far not in all ways, and in any case, such a connection is dangerous. As we know, before all the wiring was carried out with aluminum wire, now you need to use. Therefore, it is impossible to avoid the connection of aluminum and copper with a partial replacement of the electrician.
- Difficulty connecting new lines in old junction boxes. Firstly, there is not enough space for wire switching in old distribution boxes. Secondly, they are quite fragile and can break when laying a new line.
- Increased load on old wiring. If you simply decide to partially change the wiring in an apartment or house, while connecting a new cable to the old one in the junction box, an overload may occur. It is connected with the fact that an old aluminum wire of small cross section will go to the box from the shield, which most likely will not withstand the new load. As a result, you will have to pull the new cable directly from the shield, bypassing the junction boxes. And this is not only problematic, but also complicates the wiring diagram.
- Greater consumption of materials. Due to the use of “bypass circuits”, more cable will be spent on the wiring as a whole. And the work itself will be more difficult and more expensive (if you use the services of specialists).
As you can see, partial replacement of electrical wiring in an apartment and house is possible, but it is more problematic and unsafe. The low reliability of the connections, as well as the high probability of occurrence, are quite significant disadvantages.
Nuances of partial replacement of wiring
In some cases, it is not at all necessary to completely change all the wiring to a new one, even before a major overhaul. To save on replacing wiring, you can leave aluminum wire for lighting, and lay copper for sockets and individual lines. If the old aluminum wire is in good condition, it must withstand a group of fixtures. their power is not very high, besides, new LED and energy-saving lamps consume less electricity than old incandescent bulbs. In total, the replacement of only the power line can also be considered as a partial replacement of the electrical wiring with copper.
With sockets and separate lines for powerful electrical appliances, such a trick will not work. This is due to the fact that the power line must have, and for this a three-core wire is laid instead of a two-core one. Therefore, if you decide that, by analogy with lighting, you can partially change the wiring to connect sockets, you should know that this option is unacceptable.
Work performance rules
In order not to repeat and describe the process of replacing wiring several times, in this article we will provide only the key points that you need to pay attention to. So, if you want to change the wiring in parts in a private or panel house, consider the following recommendations:
- The cable must be three-core, copper, double-insulated. In an apartment and a house, we recommend that you run the VVGng-LS cable either. For sockets, select a cross section of 3 * 2.5 mm2, for a lighting group it will be enough to lay a conductor with a cross section of 3 * 1.5 mm2. A cable with a cross section of 4 mm2 can be brought out to the electric stove. In any case, you need to choose the appropriate size based on the ready-made values.
- Replace sockets and switches with new ones in any case. Sockets must be rated at 16A. In the bathroom and in the kitchen (next to the sink), put sockets with covers to protect the contacts from moisture.
- It is necessary to connect wires of different metals with special terminal blocks or by crimping with appropriate sleeves. Ordinary insulated twists should never be done.
- It is necessary to protect the line from overloads and short circuits with a circuit breaker. RCD will protect against current leakage. We talked about that in a separate article, we also talked about it. It is also possible, which will protect both from overloads, and from short circuits, and from current leaks.
- In a private house, a must. It is not always possible to organize a ground loop in an apartment. In this case, the installation of the RCD and the organization will save.
- Definitely necessary, as well as an old induction meter, if its accuracy class is 2.5.
- All work must be carried out with the power off. If you need an outlet to connect a power tool, you can power it directly from the shield, be sure to turn off all other lines.
- Before proceeding with the electrical installation, be sure to study the described by us, as well as. The information is quite useful and will allow you to avoid the most popular mistakes made by home craftsmen and self-taught electricians.
- In order not to overpay and not to change the machines and the main power lines several times, we recommend that even before performing a partial replacement of the wiring, be sure, and not a specific room, but a complete one.
- Before carrying out work, be sure to prepare all the necessary tools, as well as draw up an estimate for electrical work. The more thoroughly the preparation is done, the faster the main process will be carried out. All the necessary tools are shown in the photo:
By following all the tips above, you will be able to safely and correctly perform a partial wiring replacement. Nevertheless, after completing the work, before finishing the walls, we recommend inviting an electrician to check everything again and ring the circuit.
As a rule, every 3-5 years we renovate the rooms in our apartment. In the vast majority of cases, repairs are cosmetic in nature and include: replacement of ceiling, wall and floor coverings, as well as replacement of skirting boards, cornices, lighting and sockets. If you decide to make repairs in the entire apartment or move to a new one, we recommend that you replace the wiring. About how to properly lay the wiring, we will try to tell in detail in this article.
The content of the article:
Why you need to change the wiring
Some are interested in the question of why you need to change the wiring if the old one works quite well. In order to answer this question, it is enough to give a similar example with water pipes. Metal pipes are often replaced with plastic ones, as they are much more reliable and durable, and besides, they are not clogged with the grin that occurs in metal pipes, and therefore, the throughput of plastic pipes and the pressure in them will always be good. The same, by and large, applies to electrical wiring.Firstly, the wiring itself in houses that were built in the last century is not designed for how we operate it now. When designing houses and apartments, electrical engineers did not know that in a few years every apartment, in addition to a refrigerator, TV, washing machine and light bulbs, would also have a computer, air conditioning, a powerful electric kettle, an iron and other electrical equipment. It turns out that the bandwidth of the old wiring is lower than the power consumption of all our electrical appliances.
Secondly, in addition to the mismatch in the bandwidth of the wiring, in most old houses it was aluminum, and aluminum is not the best material for this, having a large number of disadvantages. In addition, the service life of aluminum wiring is 30 years, but it is worth replacing it even without waiting for this period in order to ensure a stable voltage supply in the apartment and extend the life of electrical appliances.
Wiring selection and installation plan for sockets and switches
Before proceeding to the description of the practical steps for installing the wiring, a few words should be mentioned about the wiring itself.What new wiring is better to lay
Of course, the best cable for wiring in an apartment is a copper multicore cable. The main advantage of copper cable over aluminum is its strength. Probably, each of you has encountered such a problem when the aluminum core of the cable, when connecting a switch or socket, simply breaks off, and this is a very unpleasant situation, with a copper stranded cable such a problem is not terrible. In addition, copper cable has better bandwidth and longer service life.To connect sockets, it is recommended to use a stranded copper cable of 2.5 squares, and for lighting - 1.5 squares. We advise you to give preference to a cable with double insulation. If you have grounding in your house or you plan to do it yourself in the future, then buy a triple cable with a special conductor for grounding.
Installation plan for sockets and switches
First of all, before performing installation work, you need to think over the plan and interior of the rooms after the repair, since on its basis the wiring of the apartment wiring will be carried out in order to know where and what cable to lay, and most importantly, how. Therefore, having such a plan, you will know where to place switches and sockets.For example, knowing the place where the computer will be installed, we will lay a separate cable there to power all computer devices that have a high total power consumption. The same applies to other powerful techniques. In places where energy-intensive equipment will be located, it is better to lay a separate cable with a single socket: electric oven, air conditioner, water tank, refrigerator, washing machine, etc. For the rest of the equipment, we carry out a “common” cable and sockets.
Hall
In the hall, we recommend installing 5 sockets with one frame, for connecting a home theater (TV, DVD player, digital receiver and audio system), a double socket near the soft corner, and a single socket in those places where you need them.
Bedrooms
As for the bedroom, it is better to do a double socket near the bed, desk and TV. In other places - as needed.
The corridor
In the corridor, it is enough to install one double socket, and if necessary, additional ones.
Bathroom
In the bathroom, the availability of sockets depends on what electrical appliances you will use in it. If there is no washing machine there, and your family members do not use electrical appliances, then it was not possible to make an outlet in the bathroom.
Kitchen
If you have a technically functional kitchen, then in the place where the cutting table will be located, we recommend making from three to five outlets in one frame, depending on the number of simultaneously used appliances. As a rule, 5 outlets are the best option to connect: a hood, a microwave oven and an electric kettle, leaving two outlets free to connect: a food processor, a bread machine, a coffee maker and others. Try to think over the number of sockets in such a way that stationary equipment that will not be folded into a box after use has its own socket for connection, so as not to stick out the plug of one equipment from the socket each time to connect another. Then we calculate the required number of outlets, as well as how much power and how many devices will work at the same time, in order to know whether to run one cable or several.
Also, we make sockets and in other places where it is necessary.
Installation of sockets
According to the established standards, the installation of sockets is carried out at a distance of 30 cm from the floor, and the installation of switches - at 85 cm. Up to five sockets can be connected to one cable with a cross section of 2.5 squares to power non-energy-intensive devices, for energy-intensive devices - preferably one. From the meter to the junction boxes, it is recommended to use a cable with a cross section of 4 squares.
How to dismantle old wiring
So, when you know where and what socket you should have according to the plan, we proceed to dismantle the old wiring. The dismantling procedure entirely depends on how the old wiring was laid: laid in special channels inside the wall or embedded in the wall, but first things first.Before carrying out all electrical installation and dismantling work, it is necessary to disconnect all apartment wiring coming from the meter, and directly power the extension cord for temporary power supply from the meter.
If the wiring was laid in the channels, then its dismantling and installation of a new one is carried out simultaneously. That is, we wind a new one to one end of the old cable, and pull out the second end of the old wiring - this way you will not need to beat the walls to dismantle the old wiring and experience difficulties with laying a new one. But if the plan for the new wiring does not coincide with the plan for laying the existing one, then strobes will need to be punched in the walls.
In the event that your apartment wiring was embedded in the wall, then first of all you need to determine where it is laid, and only then dismantle it and lay a new one. You can also find the wiring in the wall visually by seeing embedded strobes on the wall surface, or by using a special device.
How to wire correctly
Installation of new wiring is carried out as follows: we make markings on the wall where the new wiring will go. After that, with the help of a grinder and a puncher, we make strobes - the best way for the walls of a panel house. We recommend laying the wiring in the corrugation, as this is an additional safety, and the next time its replacement will not be so difficult, since the new cable can be laid by pulling out the old one.
When the strobes for the cable are made, first of all we run the cable from the meter to the junction boxes. We place the cable in the corrugation and lay it in these strobes, fixing it to the wall with alabaster, every 1-1.5 m. Next, from the junction boxes we lay the cable (also in the corrugation) to sockets, switches and lighting fixtures. The release of the cable for the socket and for the switch must be at least 15 cm. The next stage of work is the connection of the cable branchings to the trunk in junction boxes. We would like to draw your attention to the fact that the cable is connected using a special terminal block, and not using twists. Such a connection will be better and safer. When all work in the junction boxes has been completed, we proceed to the apartment power supply input.
The final stage of work is the connection of the apartment wiring to the meter. If you have an old counter and old machines, it is better to replace them. The ideal option is to invite electricians to run a new cable from the switchboard of your driveway to the meter, and also replace the meter itself. We recommend installing the meter in a special metal shield, where electric machines are also installed. As for the machines, we recommend installing a two-phase one. How many amperes should be in the machine - determine based on what equipment will work for you at the same time. The power consumption of these devices is added up and divided by 220, thus, we get the amperage of the machine. After all the work with laying a new cable into the apartment, replacing the meter (sealing) and installing the machine is completed, at the very least we connect the apartment wiring to the machine and then turn on the machines. If the machine did not knock out, then everything is connected correctly, we check all sockets and switches for operability.
Materials that are needed to replace the wiring in the apartment:
- Cable;
- Sockets and switches (frames);
- Boxes for sockets;
- distribution boxes;
- Corrugation;
- Terminal blocks;
- Electric machine;
How much does it cost to change the wiring in the apartment
If you decide to replace the wiring, using the services of special companies for this, then as a rule, one point, according to average estimates, will cost you around 500 rubles. That is, to install 2 sockets and 2 switches - it will cost 2000 rubles, not counting the materials: box, cable, socket or switch. To this must be added the cost of laying the cable from the shield to the junction box and the cost of materials. Thus, the replacement of wiring in a one-room apartment will cost you from 7,000 rubles.The cost of replacing wiring with your own hands will be several times cheaper, since for this you only need to buy the necessary material, and also have: a grinder with a disk for concrete, a hammer drill with chasing attachments, alabaster and utility tools.
First of all, this fire hazard. Secondly, it is a danger to life and health (a current up to 36 volts is considered a safe current for a person). And thirdly, bad outdated electrical wiring is unstable operation and equipment failure, a breakdown of expensive household and lighting fixtures.
How to realize that the house has old wiring?
First of all, you need to pay attention to the electrical panel. Usually, this is where the electricity meter is installed. If there are still old Soviet plugs in the shield, then you have old wiring! Everything is obvious here - the wiring in the house is rotten, with aluminum wires. The second, important sign of old electrical wiring is if you are periodically shocked in the most unexpected places. Don't wait until next time - call an electrician immediately! And if possible, be sure to replace all plugs with automatic machines. Don't wait for them to burn out next time. Replacing traffic jams with automatic machines is best entrusted to a professional, - call an electrician 1 hour and job done! Remember! That an untimely replacement can cost you much more.
"Fireproof" wooden shield, with melting wires
What is the danger of aluminum wiring?
The life of aluminum wires is much less than that of copper wires. Aluminum is more prone to oxidation, and is less flexible and softer than copper alloys. The problem of aluminum is especially pronounced at the joints and kinks in the wiring. High humidity and poor contact also accelerate the oxidation process. Subsequently, this leads to overheating and burnout of the contact.
aluminum wiring
The old aluminum wiring has a single insulation, which is simply unacceptable according to modern rules! Single insulation is fraught with current leakage into walls or other structures of the house. In a modern home, a double-insulated wire is simply needed, which is called a cable. According to the new rules, only cable is allowed in apartments and houses.
This is how current passes through a person.
Another disadvantage of old wiring is the absence of a third, so-called "safe" wire, known as the ground wire. In the old five-story buildings, Khrushchev, Stalinist, and panel houses, up to the construction of the early 2000s. - The ground wire was simply not provided! Therefore, installing sockets with grounding, without replacing all the wires, does not make any practical sense. In special, ridiculous cases, this can even play a cruel joke if the installation of sockets! The new rules require grounding all electrical equipment, and, accordingly, the presence of a safe wire in all electrical wiring. What is the term grounding, and why it is needed can be read.
Soldering boxes and twists
Standard junction box layout
Probably everyone has heard such a thing as twisting. In old electrical wiring, twisting is normal. A good twist is no worse than, for example, a bolt clamp. The main and necessary condition is that all twists and connections of wires must be located in junction (junction) boxes, which serve as a place for safe switching (connection) of wires. According to the rules, it is not allowed to close access to the junction boxes, cover them up or glue them with wallpaper. Usually junction boxes with twists are located above the light switches under the ceiling.
old twisted wires
Twisted aluminum wires, in these places, eventually become unusable, especially with high humidity and poor-quality installation. Signs of problems in the junction box are: blinking light, electric crackling under the ceiling, burning smells (not always obvious), or a partial lack of light in the apartment. In such cases, it is necessary to look for and open old junction boxes in order to sort out (rewire). To do this, unwind the old twists, and put the wires on special terminal blocks, having previously processed the ends of the wires.
Terminal blocks for connecting wires
A fairly common (even too common) and unpleasant problem is the twisting of copper wires with aluminum ones. The fact that you can’t do this should probably be taught in school! And the fact that this is one of the main causes of the fire is not known to many! Thin wires with a section that does not correspond to the load are the second factor in the causes of fires! Any wire that passes current through itself heats up, and it heats up in direct proportion to the load. That is, any wire can be heated like a soldering iron - just apply a good load to it! If you see that, for example, a household heater is hanging on thin wires, turn it off and call an electrician immediately, - Old electrical wiring is the most common cause of a fire!!! .
Twisting - you can't do that!
Danger of old sockets and switches
Old electrical installation products: sockets and switches do not meet modern electrical safety standards. It is simply impossible to insert a plug into an old Soviet-style socket without additional effort, and when you try to insert it with a blow, the socket usually breaks.
The main problems in old wiring are most often manifested in feed-through sockets. Sockets through which electricity flows from a source (another socket) further to the next socket or consumer are called pass-through sockets. Usually, at the point where the wires are connected in the outlet, a break occurs. And the worse the contact, the higher the load on the junction. High currents can cause overheating and even fire. The entire load in the apartment can go through one outlet, and if the outlet is old and constantly in use, there is a high probability of weakening the contact in it.
It is clear why most often it is the old sockets that fail. In the best case, some of the sockets in the house stop working, but in an unsuccessful scenario, they simply burn and melt. And the saddest thing is that no machine other than an RCD will save you from this.
In general, through sockets are normal, and they are allowed by the rules. Not a single modern wiring can do without them. First of all, this is due to the enormous cable savings. High-quality, and correctly installed through sockets, cope with their task with a bang. The main thing is not to exceed the calculated loads on the line with sockets.
The same, but not to the full extent, applies to light switches. Of course, the load on the switches is much less than on the sockets, but they can also burn like the sockets in the photo. By the way, switches on a string, this is another sign of the realization that something is wrong with the wiring. The socket in the old socket rests on pieces of wood
Lighting. How do you know it's time to change things?
It is necessary to pay attention to lighting fixtures: old chandeliers, sconces, lamps. The weak point of old lighting fixtures is cartridges! Over time, the plastic of the cartridges dries up and bursts, the contacts overheat and oxidize, hence all the problems arising from this. Often, light bulbs explode due to such cartridges, or leave a base inside the cartridge. Replacing cartridges in old chandeliers is not cheap, as it is very painstaking work and requires a lot of time. It is much easier and cheaper to buy a new lighting fixture.
Be careful with electric current! Don't have the funds to replace the wiring? Do it at least partially! Any improvement in wiring is an additional insurance for your safety, which reduces the likelihood of any wiring problems by an order of magnitude, and will significantly reduce energy costs.
Old pre-war wiring in an emergency building on Stary Arbat.
Exclusive photo from our electrician
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