How to remove old wiring in an apartment. How to replace old electrical wiring in a house

Old-style apartments, called “Khrushchev-era” apartments, have many problems with electrical wiring:

Single Insulated Aluminum Wires

Lack of grounding

No devices protective shutdown

Insufficient number of sockets in living rooms and kitchen

The wiring was done using the branching method.

All this does not suit the needs at all modern man and his apartment, where several electrical appliances are located and often work simultaneously (stove, microwave, electronics, washing machine, boiler, air conditioner, etc.).

Stages of replacing wiring in an apartment

Chaotic behavior when replacing wiring is not welcome, so you need to adhere to a strict plan:

Draw a wiring diagram

Select machines and wires

Prepare a wiring plan and have it approved by the energy service

Triple the makeshift

Route the wiring

Install RCDs, sockets, switches and electrical appliances

Important! Before work begins on replacing the wiring, it is necessary to arrange protective grounding.

How to make a wiring diagram

This diagram is a special drawing of an apartment, which indicates:

Location of sockets and switches

Lighting sources

Electrical appliances

Distribution boxes

Electrical panel

All wires

In modern apartments, each group of energy consumers has its own cable. Thanks to this, in the event of a breakdown, the electricity is turned off only in the problem area, while the rest of the apartment remains operational.

There are separate requirements for the bathroom - there must be an RCD here, since this is a room with high humidity.

The wiring diagram looks something like this (naturally, individual for each apartment):

Selection of machines, wires, drawing up a diagram

For modern apartments, it is necessary to replace the input circuit breakers and install an RCD.

The selection of machines is carried out in this way:

For the entire apartment: standard rating from 25 to 32 A, RCD - 50 A and 30 μA

For the kitchen: 25 A, RCD 30 A and 30 µA (wire cross-section - 4 mm2)

For air conditioner: 16 A, RCD - 30 A and 30 μA (cross section - 2.5 mm2)

For lighting: type B, nominal - 10 A

For sockets: nominal - 16 A

Aluminum wires must be replaced with copper ones, which conduct current much better and last longer due to their flexibility and strength.

Attention! Under no circumstances should you connect copper wires with old aluminum ones, since an oxidation process will begin at the junction, which will lead to destruction of the contact.

The most commonly used wires in apartments are VVG and VVG NG (non-flammable wire).

For sockets, a 3-core cable with a cross-section of 2.5 mm2 is selected. For lighting devices, a 2-core cable with a cross-section of 1.5 mm2 will be sufficient. But for a fairly powerful electric stove You need a 3-core cable with a diameter of 4 mm2.

In accordance with the selected machines, another diagram is drawn up - power supply.

Its graphical appearance:

And schematic:

You need to start drawing it with the meter (in the diagram - kWh), then comes the RCD and all other elements of the electrical network.

Info! In the diagram, the wires are crossed out with slashes - this means that there are only two wires: neutral and phase. If grounding is still present, then there should be 3 dashes.

The letters L, N and PE are the foreign designation for phase, neutral and ground wires. In the diagram, the ground wire (PE) goes separately.

To clarify what certain designations look like, you need to refer to the Rules for the Construction of Consumer Electrical Installations (PUE) or GOST 2.755-87.

How to set up an electrical wiring plan

The most sensitive and important point is drawing up an electrical wiring plan. After all, it is this document that will be sent to the energy service for approval.

He looks like this, already quite serious:

To do it quickly and correctly, you need to take the plan of your apartment from the BTI and draw it on a blank sheet of the appropriate size. In this case, there is no need to transfer any old designations - the contours of the rooms, the area and everything that does not concern electrical wiring, placement should remain electrical appliances, lighting, sockets. All this will need to be applied independently, in accordance with what is planned when replacing the wiring.

There should not be any blots on the sheet; it would be better to redraw everything completely later.

After this, if everything is drawn up correctly, the plan will be approved and you can begin to dismantle the old wiring and install the new one.

Wiring installation

Before you begin dismantling and installing wiring, you need to collect all the necessary tools:

A hammer drill with a drill size of at least 16 mm

Core drill (90-100 mm) and chisel (25-30 mm) for concrete

Grinder with a circle for cutting stone

Phase indicator and multimeter

Soldering iron

Assembly knife

Screwdrivers, side cutters and pliers - all with insulated handles

Flashlight and electric portable lamp

Alabaster and chapelle

Level and cord for checking the accuracy of punching grooves

As well as devices and materials:

Socket boxes

Electrically conductive lubricant

• Corrugation for cable

  Switchboard

Temporary structure

When working with electrical wiring, you will definitely need electricity to operate the hammer drill, grinder and light supply. To do this, you will need to arrange a temporary structure, which is a structure of a wooden or plastic beam, a socket and an extension cord. All this is removed from the apartment and is powered by an external meter.

Removing old wiring

Important! Before any work (even at the stage of setting up a temporary shed), you must turn off the electricity, check its absence with a multimeter, and only then begin dismantling the wiring.

Dismantling begins from the distribution boxes, which are usually located under the ceiling. Having opened the box, you need to find the input wire and remove it or cut it and insulate it. Then you can remove all other wires.

Wall grooves (when laying wiring in new grooves)

Walls can only be tapped in two directions: horizontal and vertical. Any curvature will then come out sideways and lead to emergency situations.

Using a hammer drill, the boundaries are determined: the width and length of the groove, which are then gouged out manually with a chisel. If you need to make a corner, you will have to make an oblique cut using a grinder and knock out a hole, then the corrugation with the cable will lie flat and without sharp bends.

To hollow out a hole for the socket box, you need to use a crown that fits onto the hammer drill.

Important! The crown is only suitable for walls made of brick; for concrete walls you will need to use a chisel, since the crown will simply crumble when it hits the reinforcement.

All holes for socket boxes are made at the distance at which it will be convenient to use them.

Advice! The outlet for the air conditioner should be placed higher than all the others so that the cord from the equipment does not dangle in plain sight.

Wiring

Before you start laying the wires in the grooves, you need to prepare their corresponding sections, and the corrugation for them. Then, on the floor, the wires are pulled into a corrugation, and all this is placed in the grooves, and the ends of the wires are inserted into the socket boxes.

The socket boxes and grooves are covered with a solution: the socket boxes - around the entire circumference, and the grooves - in separate sections every 0.5 meters.

As soon as the installation is completed, you need to insert the input wire into the electrical panel and lubricate it with thermal conductive paste. All this is well secured and connected to the grounding terminal, after which the shield is secured with dowels to the wall.

Next, you need to turn off the temporary structure, insert the wires from the meter and the grounding wire into the panel, which must be connected to the panel body. The drive from the meter is isolated and placed in the incoming electrical panel.

Then the entire structure is secured and you can begin plastering the walls.

Important! Before plastering, you must first push rags or foam rubber into all the grooves and cover the shield with film.

The final stage of wiring replacement

When everything is plastered and painted, all that remains is to clean the socket boxes and install sockets, switches and lamps.

Now the most important thing: each branch of the wires must be checked for a short circuit by a tester. To do this, you need to apply current for a while and use the indicator to find the zero and phase that come from the meter. And only after they have been determined can you enter necessary wires to the appropriate terminal blocks.

Important! Even after the wires are inserted into the terminal blocks, you need to check them all again for a short circuit, and only then turn on the main circuit breaker and supply current to the apartment.

After the control check, you should check the operation of sockets and lamps.

Convenience of repairing new electrical wiring

After installing new electrical wiring, you don’t have to worry about its serviceability for a long time. But if problems arise for some reason, then it will be enough to use the wiring diagram drawn up earlier, find the area where the problem arose, and check each junction box for proper connections and, using a “test,” identify the damaged wire.

Advice! A dialer is a very useful device for every home craftsman and owner of hidden wiring. It consists of a regular battery, a light bulb, connecting wires and clamps.

Independent replacement and repair of electrical wiring is the most difficult and important stage of apartment renovation. They require a careful approach to everything: developing a wiring plan, laying wires, connecting energy consumers. It often happens that just one mistake can cause a fire.

Training video on replacing wiring

To ensure a comfortable stay for a person modern level More and more electricity consumption is required. But increased energy consumption means an increase in the load on electrical wiring, which in the vast majority of cases is not designed for the total power of the connected electrical appliances.

The fast pace of human life often requires the simultaneous operation of many devices in the house, without the possibility of connecting them at different times to distribute the load evenly. Therefore, in order to ensure reliable and uninterrupted functionality of all electrical equipment in the house, the old electrical wiring must be replaced.

Reasons for replacing electrical wiring

Increased electricity consumption is one of the reasons why electrical wiring is planned and carried out, or, as people say, electrical replacement.

The technician installs new wiring

Although this is not the main reason, and due to the high cost of repairing electrical wiring, even if done by hand, users are looking for ways to optimally distribute the load on old wires.

For example, replacing the electric meter and using electric heaters, a washing machine, and powerful kitchen appliances at night will reduce the cost of paying for electricity, and circuit breakers will not be tripped due to overload.

Variety of two-tariff electricity meters

Such powerful electrical appliances as a refrigerator, boiler, air conditioner remain connected to the network almost around the clock, consuming electricity. But by purchasing energy-saving models and installing economical modes, you can reduce electricity consumption and the load on the network.

Replacing wiring for electrical safety

But what you really can’t save on is electrical safety. The insulation on old wires deteriorates, leading to significant leaks. electric current, which in itself is unsafe, and also leads to unnecessary energy consumption.

Unsafe old wiring

Current leaks in outdated electrical wiring will not allow increasing electrical safety equipment operation. If the user installs it in the shield with his own hands, they will knock out, reacting to leaks in the wires.

Besides, mandatory element Modern wiring is a PE protective grounding conductor. Naturally, in addition to updating the electrical wiring, you will need to replace the socket at each point. Sockets must have a grounding contact.

Grounding socket

Another reason why outdated electrical wiring must be replaced is the material of the conductors. According to current PUE standards, in residential buildings wiring must be carried out with conductors with copper wires, while in most cases, aluminum wires are installed in older houses.

Quote from PUE

Often, the need for major repairs of a house or apartment prompts the owner to replace the electrical wiring with his own hands or with the help of a specialist. This combination of work will significantly reduce repair costs.

Start of major renovation

Sometimes, the urgent need to replace electrical wiring forces the owner to undertake a major overhaul of the entire house. This forced measure is associated with the installation of hidden wiring, which cannot be done without large-scale repair work.

Correct organization of electrical wiring replacement.

When replacing electrical wiring with your own hands, the main difficulties arise when the work is not organized correctly. For example, many resources on the Internet advise starting with dismantling the old wiring.

But by turning off the circuit breakers in the panel and starting to dismantle the wires, sockets and switches, the apartment owner is left without electricity. Very often, replacing a socket, switch, or installing distribution boxes requires the use of light sources and power tools for drilling holes in the socket boxes.

After turning off the old machines, the apartment owner is left without electricity

Therefore, before turning off the machines, you should take care of a temporary backup power line to provide power to tools and light sources. The extension cord, which may be homemade, must be able to withstand the power of power tools, lighting systems, and electrical appliances required for life support during repairs.

Approval by official authorities

To prevent the repair from taking too long, everything must be completed and drawn up first.

Typical residential wiring diagram

It is better to coordinate this scheme with the controlling authorities - electricians and firefighters. After repairing the electrical wiring, the received certificate and work report will help the owner of the apartment evaluate it more favorably in the event of selling the property.

If it is planned to replace the electric meter, then all organizational issues must be agreed upon with the electricity supply management company so that there are no delays and downtime of the already connected electrical wiring.

It is necessary to agree whether the owner will replace the electricity meter with his own hands, followed by sealing, or coordinate the exact time of the technician’s arrival with the authority of the relevant organization.

Preparation of tools and materials

The calculation of automatic machines by power and their number in the panel is described in detail in the sections of this site, and you will need to familiarize yourself with them before planning repairs and replacement of electrical wiring yourself.

Ratings and number of machines in a typical residential distribution panel

In addition, you will need to draw up a wiring diagram so that it meets both safety criteria and the needs of the inhabitants of the apartment or house. The diagram must indicate all sockets, switches, junction boxes and light sources.

The most important decision, which will determine the entire cost of the work performed, will be the choice between hidden and external electrical wiring.

A description of the advantages and disadvantages, as well as the wiring process, can be found.

According to the drawn up scheme it will be necessary calculate length cables and wires necessary for installation and connection of machines in distribution panels. When purchasing cable products, you need to be wary of counterfeits, paying attention to the actual cross-section of the cores.

Formula for checking wire cross-section relative to core diameter

When choosing circuit breakers For the input and distribution panels, you also need to be wary of counterfeits and require a quality certificate for the purchased products.

Wire installation

It will be necessary to decide what method will be used in the junction boxes. The most reliable is, but for home craftsmen this installation method is the least accessible, due to the high cost of the device and the lack of specific operating skills.

Electric welding of wires with a special welding machine

To make connecting wires in distribution boxes, replacing a socket or switch as simple as possible, Wago terminal blocks were invented, which have gained great popularity among professionals and home craftsmen.

Installation in a distribution box using Wago terminal blocks

Unfortunately, there are many fake terminal blocks, and users themselves do not always correctly install and calculate the power of the product. Therefore, many professionals agree that the most reliable and profitable way to replace electrical wiring yourself.

Soldering wires in a junction box

According to the chosen installation method, the necessary tools and additional Consumables– electrical tape, heat-shrinkable tubes, screws, dowels, staples, etc.

Dismantling old electrical wiring

As already mentioned, dismantling and replacing the electric meter should only be carried out according to agreement with official services. The owner of the property can carry out the rest of the work at his own discretion.

The most common change is the placement of circuit breakers - if previously they were all located in a common switchboard, now owners prefer to install their own switchboard in the apartment.

Own apartment distribution board

As a rule, the apartment has long served its useful life and must be replaced. In the case of sockets, in addition to wear and tear, the reason for replacing them is the need for a grounding contact.

From a practical point of view, it makes sense to remove old electrical wiring if new wiring is to be installed in a given location - the resulting ditches after removing the wires will eliminate the need for chiselling the walls.

Laying a new cable in the ditch created after removing the old wiring

After dismantling the old electrical wiring, including sockets, switches, cables and light sources, you can begin installing new wiring.
An important point is the nature of the wall covering and the choice of type of electrical wiring. For example, when laying wiring under drywall, there are rules and methods for carrying out the work.

Laying wiring under drywall

Brief description of the process of replacing electrical wiring

All stages of subsequent electrical installation can be divided into several points, which are described in more detail on this website:

• Acquisition necessary tools electrician;
• Grooving walls for hidden electrical wiring;
• Laying cables in a groove, box or;
• Fixation of socket boxes and distribution boxes;
• in distribution boxes;
• Connecting switches and sockets;
• Checking and continuity of electrical wiring;
• Sealing of cable channels and cosmetic repairs.

Thus, having familiarized yourself with the process of implementing the points described above, you can replace the electrical wiring yourself, significantly saving money.

It would be irrational to replace old wiring without accompanying major repairs, especially if we are talking about its hidden type. These are large expenses for materials, payment for electricians and repairmen. However, you can save a lot of money on paying someone else's labor. To do this, you need minimal knowledge of electrics and a lot of free time. You will find the time, and we will tell you how to change the electrical wiring yourself.

All work on replacing electrical wiring must be performed one after another, without changing the sequence. Otherwise, you may end up buying too little or too much material, making the wrong cable connection, or running the wire in the wrong place. To prevent this from happening, perform the work in the following order:

1. Determining the scope of work;
2. Drawing up a diagram;
3. Calculation and purchase of materials, preparation of tools;
4. Dismantling or cutting old wiring;
5. Marking new wiring;
6. Installation of new wiring;
7. Control check.

If the wiring check was successful, then the overhaul can be completed. However, it has nothing to do with replacing the old wire.

When is it time to change the wiring? And what part of it?

Depending on the scale of work, wiring replacement can be:

1. Partial;
2. Full.

Partial replacement is justified in cases where:

• Only one line of non-old wiring was damaged mechanically or by fire;
• The load on one or more lines has increased significantly, and the wire cannot withstand it, while the distribution panel and the rest of the wiring are still suitable for use;
• There is not much time left before the planned overhaul, and the wiring needs fixing right now. This only applies to old wiring in cases where it is impossible to start repairs at the moment and you need to wait.

Signs indicating the need to completely replace the old electrical wiring:

The wiring in Khrushchev especially needs replacing. This apartment has been in use for more than 50 years. In the last century, all wiring was made of aluminum wire, not protected by corrugation. But at that time it was enough: how much do a lamp, a stove and a TV need? Today they have added washing machines and dishwashers, microwaves, vacuum cleaners, kettles and other household appliances. Therefore, in Khrushchev-era apartment buildings with old wiring, a fire hazard situation is created and traffic jams are constantly knocked out.

Wiring diagram

Before you change the wiring in your apartment with your own hands, you need to draw up a diagram of the new one. And it does not have to coincide with the old one, which often contradicts fire safety requirements.

The scheme is compiled arbitrarily using symbols. You will need to recognize the markings for outlets, switches, junction boxes, and junction boxes. You come up with the designations for them yourself. But mark the route along which the wire will be laid with a line. Moreover, for each wire (zero, phase, ground), come up with your own color.

It might go something like this.

The imagination that you can use when drawing up a new electrical wiring diagram is limited by the following rules:

• Do not connect grounding socket contacts to water supply and heating pipes or to a common wire. For this purpose, a grounding cable must be provided;
• The electrical wiring route is laid only vertically or horizontally, angles of only 90 degrees are allowed;
• The wires should not intersect, and at least 0.3 cm should be left between them;
• The distance from the route to the floor/ceiling should not be less than 15 cm, and between it and the door/window opening - 10 cm;
• Switches on the outside or inside of the room, but always on the handle side.

• Switches and sockets are placed in a row at the same level;
• Old standard: installation of sockets at a height of 0.8-0.9 m, and switches - 1.5 m. New standard: everything at a level of 0.8-0.9 m, but in the kitchen there must be a set with a distance of 10 cm from the tabletop. Sockets are allowed at a distance of 15 cm from the floor;
• For a room, there is 1 socket for every 6 squares. For the kitchen - 1 socket for every 2 squares;
• In adjacent rooms, place sockets and switches opposite each other.

The rules for drawing up the diagram are clearly presented in the figure below.

Devices and materials

According to the diagram you will see what materials and in what quantity you will need them. But buy 20% more. This way you will protect yourself from inaccurate calculations and possible damage to materials during work.

You will need:

• Distribution panel – 1;
• Cable. For complete replacement of any wiring - copper. For partial replacement of copper wires - also copper, and for partial replacement of aluminum wiring - aluminum. In most cases, copper with a cross section of 2.5 square meters is chosen. mm for sockets, 4 sq. mm for the stove and 1.5 sq. mm for lamps. The optimal conductor cross-section can be selected using the table below the list;
• Protective automation(residual current device and circuit breaker) to prevent overload, electrical leakage and short circuit. You can buy a “2 in 1” device: differential machine. For the lighting line, the automation is taken at 16A, for socket families - at 25A, and for powerful consumers - 32A. The input RCD should operate at 62A, and the circuit breaker – at 50A. For each line - an RCD and a switch, or just a circuit breaker;
• Distribution boxes(round ones are easy to install, but square ones accommodate more connections). Their number corresponds to the number of wiring branches;
• Sockets. Preferably with grounding, and for the bathroom - with an RCD;
• Switches;
• Terminals for connecting cables.

Additionally, corrugation may be needed (if hidden wiring) or cable channels (when open).

For electrical installation work you need the following tools:

• Hammer or drill with three operating modes;
• Various hammer drill attachments;
• Grinder or wall chaser (optional, as you can use a hammer drill for this);
• Standard electrician's kit (nippers, pliers, scissors, electrical tape, screwdrivers, hacksaw and knife);
• Multimeter with dialing function.

These are tools for hidden type electrical wiring. For open type You will also need a long wire about 1.5 mm thick. With its help it is convenient to pull the cable through the channel.

Getting rid of old wiring

Attention! From this stage, all work is carried out after the entire apartment has been de-energized!

New wiring in the apartment is installed with your own hands only after removing the old one. For this:

1. Look around the walls for old wire routes. Since cable installation starts from the distribution boxes, you need to find plastic lids or protrusions under wallpaper in the walls. The cover needs to be removed. In the case of open wiring, the search is simple;
2. Disconnect the cables in the junction boxes;
3. Pull the wires out of the grooves.

Sometimes dismantling old electrical wiring requires serious damage to the walls or floor if it ran under the floor covering. In this case, it is possible to maintain the finish, but then the wires are cut and their ends are carefully insulated. However, the markings of the new wiring should not coincide with the old circuit, otherwise you will have to destroy everything. This method is relevant when the floor has an expensive coating that lasts for decades. Then the new cable is laid along the wall.

How to make markup?

The marking is carried out according to the drawn up diagram using a ruler or tapping cord. It must be smooth and accurate: it is along it that grooves will subsequently be made or cable channels will be laid.

To make a line with a cord, you need to attach its free end to starting point route the wire and stretch it to the extreme point. In it, you need to pinch the cord with your finger, and with your free hand, pull it in the middle, and then quickly release it. It will hit the wall, leaving a clear line on it.

Installation of new wiring

Now directly about how to change the wiring in the apartment yourself. The new cable can be laid in two ways: openly and hidden. But regardless of the type of electrical wiring, the first step is to install a shield.

We install the distribution panel

In modern apartments there is a special place for the distribution board in the form of a niche to which the power cable fits. Then all the trouble comes down to fixing the shield in it and installing circuit breakers and RCDs connected to the cable into it.

In Soviet apartments, the shield is mounted in a place that is chosen independently. It should be easy to access. Since the power cable is not connected to the apartment, it is necessary to drill a wall in the selected location to pull the cable through, which is used to connect to the access panel. For these purposes, only VVGng 5*6 is suitable.

Typically, the insides of the shield are arranged as follows:

• Below is the earth;
• Above – zero;
• Between them are machine guns.

The input cable must be cleaned and the blue wire connected to zero and the yellow wire to ground. The white wire is connected to the machine contact on top, where an additional jumper will be installed leading to the machine next door.

Cables VVGng 3*2.5 and 3*1.5 are connected according to the diagram: the phase conductor is to the lower circuit-breaker terminal, and the neutral to the ground is similar to the first wire. If you have provided for the installation of an RCD, then first the phase with zero is connected to it. They are connected to the terminals of the machine through a disconnect device.

We mount it hidden

Replacing the wiring in a panel house with your own hands is a simple matter. The panels already have grooves for wires. And you don’t need to ditch anything. In other apartments you will have to work hard:

Attention! The work of making grooves is very dusty. Therefore, you need to protect yourself with a respirator and special glasses.

We mount openly

Open wiring is rarely done in apartments, so it cannot be completely ruled out. And it is mandatory to do it in offices and other in public places. It may not be very aesthetic. But it has an important advantage - the ability to work with it at any time, regardless of repairs, since dismantling does not require damage to the wall finish.

In the case of open wiring, everything is simpler: there is no need to make grooves. You just need to stretch the cable along the wall according to the markings. As for distribution boxes, everything is the same. Only they are not installed inside the wall, but are fixed on its surface.

If you want aesthetics, cable duct is for you. Today their coloring is carried out even under natural wood. Then the cable must first be pulled through the channel, and then secured to the wall according to the markings.

Wiring check

After laying the cable, use a multimeter with a continuity function. Having called each cable and found no errors (the zero should not be connected to the phase and ground, the ground should not be connected to the zero and phase, and the phase to them) in the electrical wiring, you can begin checking the operation of sockets and switches. If everything works, it's time to seal the grooves. A putty mixture is suitable for this. When the composition dries, the walls can be finished with any material.

Improper electrical wiring has caused many fires and deaths. Therefore, before you replace the wiring in your apartment with your own hands, think carefully about whether you can handle it? If there is even the slightest doubt, entrust the matter to a specialist. Safety costs more than the cost of qualified assistance from an electrician.

The need to replace electrical wiring in a private home with a more powerful one is encountered if the home line is outdated and cannot withstand the load from modern household appliances, such as an electric boiler or stove. Next, we will look at modern electrical installation solutions, as well as a visual video lesson showing how to replace the wiring at home with your own hands.

Determining the complexity of the work

So, first you must analyze the old wiring and find out the following points:

1. Is it present on the site? This is very important, because without a grounding loop you can suffer if household appliances fail or insulation breaks down.
2. Is it possible or necessary to completely replace the electrical system in a private home? Perhaps some rooms have recently been renovated and, accordingly, a new, more powerful cable has been installed that will meet modern requirements.
3. Can you carry out the electrical installation yourself or will you have to hire a specialist for this? It should be noted here that replacing electrical wiring in a house with your own hands is not difficult, but the undertaking is labor-intensive and requires special care. If you don’t doubt your abilities, of course, do everything yourself. Otherwise, first find out the cost of the master’s work, because... To do this you will have to pay a considerable amount of money.

Having collected all the necessary information about the complexity and scope of work, you can get down to business. The video explains in detail whether it is worth completely replacing the old wiring with a new one:

Pros and cons of completely replacing electrical wiring

Creating a wiring diagram

On at this stage It is necessary to think over the cable routing scheme through the air and indoors. It is also necessary to correctly design the one that will be located on the site of the house. We recommend that you familiarize yourself with the following options:

As for grounding, it is better to give preference to the “triangle” system:

Grounding in a private house is usually done like this: three metal pins (or corners) are driven in at an equal distance from each other so that they are at the vertices of the triangle, then they are scalded with a metal strip - a grounding rod is obtained, to which the wire from the panel can be laid. We talked in detail about how to make grounding in the article:.

Having created the project, you can proceed to counting materials and selecting the most suitable elements for replacing the electrical wiring in the house with your own hands.

We count and select materials

The first thing you must calculate is the cross-section of the cable that will run through the air and inside the living space. This stage is very important, because It is precisely because of the diameter of the conductors that the wiring in a private house is replaced (an old line, most likely with aluminum conductors of a small cross-section). It’s not complicated, so you can easily do it without the help of a specialist.

Inside a private house, from the distribution boxes, the electrical wiring will be divided into several groups of different sections:

• for lighting – 1.5 mm 2;
• for sockets – 2.5 mm 2;
• for powerful electrical appliances (for example, a boiler) - 4-6 mm 2;

Important! To connect powerful electrical appliances, we lay a wire calculated according to the load and current requirements, for example, to connect a single-phase electric stove, according to SP 31.110-2003, it is necessary to lay a cable with a core cross-section of at least 6 square meters. mm. In any case, pre-calculate the power cross-section.

It should be noted that the wiring can be done as follows: open method, and hidden. Which option to choose when replacing is up to you to decide. However, if the building is brick, there are many more advantages, therefore the technology will be presented in relation to this method. If you decide to replace the electrical wiring in a wooden house, it is better to use.

As for the protective automatics - and, they are selected for each group of wires separately. A 10-amp circuit breaker is connected to lighting, 16A to sockets, and powerful household appliances to a circuit breaker that corresponds to the current consumed by the appliances. We described how to convert power into current and vice versa in the article:.

All lines are protected by group RCDs, their current can be calculated, but in most cases they use an unspoken rule - the differential current (also known as tripping current or leakage current) of group RCDs:

• for the bathroom – 10-30 mA;
• for other rooms – 30 mA (according to 7.1.79);
• for input 100-300 mA (according to PUE 7.1.84).

The rated current of the RCD must be equal to or one step greater than that of the circuit breakers that protect this circuit. This means that if the machine is rated at 16A, then the RCD should be rated at 16 or 25A. Calculation of RCD leakage current for individual devices and network leakage is carried out in accordance with PUE 7.1.83.

It is recommended to use high-quality sockets and switches so that they can also withstand current loads(marking in amperes is indicated on the housing). For open wiring in the house, you must additionally purchase corrugation or electrical skirting boards, depending on what you choose in your case. After selecting all the components, you can count their quantity and go shopping.

Removing the old line

At this stage, you are already starting to directly replace the electrical wiring in a private house with your own hands. First, turn off the power at the entrance to the housing (usually a distribution panel is installed in the corridor). After this, you empty the rooms of furniture for a hassle-free renovation.

The old electrical wiring must be completely replaced, starting from the junction boxes. If for some reason it is impossible to pull the cable out of the groove, it is better to leave it, only carefully insulating it on both sides. Old grooves can be used for new electrical installation if you are satisfied with the former location of switches and sockets. If you want to change the route, make new grooves according to the created pattern. Once all the old line has been removed, you can proceed to laying a new one.

Let's start installation work

We discussed it in detail in the corresponding article, which we recommend that you read. So that you understand the complexity of the work, we provide you with brief step-by-step instructions for replacing electrical wiring in the house:

1. The walls are prepared: the wiring route is marked with a pencil and a building level in accordance with the drawn diagram.
   
2. Using a grinder or wall chaser (shown in the photo), grooves are created in the wall, which will serve as a seat for the entire power line. By the way, you can, if you want, of course.
   
3. Socket boxes and distribution boxes are installed.
   
4. The cable is fixed in the grooves using special clamps or alabaster (do not rush to plaster the walls, as it is better to do this after the replacement of wiring in the house is completely completed).
   
5. Sockets and switches are installed.
   
6. The automatic protective equipment is connected in the distribution board.
   

Hello, dear readers and guests of the Electrician's Notes website.

In the previous article, I told you about preparing to replace the electrical wiring in the apartment. Here is a link to. So, let's proceed to further study the material.

But before you start studying new schemes, you need to become well acquainted with existing ones. standard schemes and projects.

I will repeat to you once again that in order to replace the electrical wiring in the apartment, it is necessary to develop a project, and it cannot be otherwise. Because there are many important questions that need to be given sufficient attention:

• calculation of the power of installed equipment
• selection of protection devices (automatic machines, RCDs, difavtomats)

Here are a few examples for clarity: an office power supply project and.

In old houses and apartments there are several standard schemes.

In this scheme, the PE protective conductor is used only for the electric stove. It is not used for group lines.

Most often, the electric stove is powered by a three-core aluminum wire with a cross-section of 4 square meters. mm, for example, APPV (2x4), and the power supply for group lines is with a two-core aluminum wire with a cross-section of 2.5 sq. mm, for example, APPV (2x2.5).

If you care about your safety, then you need to periodically check the quality of your electrical wiring. Any (ETL) at your place of residence will help you with this. She has a number of special devices for this. It is also necessary to switch to the TN-C-S grounding system. About it .

I'll bring you clear example: You bought a jacuzzi bathtub or a dishwasher for your apartment. We read the passport and instruction manual, which states that the bath must be powered from a 380/220 (V) network with a grounding system (3-wire network - phase, zero and ground) and an RCD must be installed in the line. or difavtomat.

What kind of house do you have - panel or brick?

Our house is a panel house built in 1991.

Question: is it possible to carry out wiring for 5 sockets from the switchboard in the apartment to the kitchen without using junction boxes (a separate cable from the switchboard goes to each socket)?

Of course it is possible, even necessary. Recently, most projects have been done this way with the goal of using a minimum of junction boxes. This option may be more expensive, but each junction box is an additional connection of wires.

Dmitry, good evening.
Tell:
the apartment is old
ancient shield in the apartment
powered by two aluminum wires.
Major renovations have begun. I do almost all the wiring with a 3-core cable. Where can I get earth for sockets?
Alive on the 1st floor. There is a common electrical cabinet nearby. Maybe stretch one core from there, if there is one there.
Thank you

If the main electrical wiring lines in your house are made according to the new standards, then the PE protective conductor must be present in the floor panel. In this case, you just need to connect to it and bring it into the apartment via a PE bus. If there is no “ground” in the floor panel, then check with the management company employees whether there is a ground loop in your house at all? If not, then do the wiring in the apartment as expected (phase, neutral, ground). Later, after the reconstruction of the main networks in the house (if there is one), you will connect the PE bus in the apartment as expected.

Thank you.
I'll try to clarify about RE in the housing office.

Found it out.
There is no earth in the floor panel, there is no ground loop in the house, because... old fund.
Reconstruction of the main networks in the building is not expected.
I carried out all the wiring in the apartment with a three-core cable.
Tell me what to do now with the RCD (how to connect it in my case)? And in general, what to do with the missing land, how to protect yourself and your loved ones?
Thank you.

Vitaly, as I already said, it is forbidden to install an RCD with such a power supply scheme, according to the PUE. Therefore, the opinion of electricians was divided. Some people recommend installing, while others stubbornly follow the instructions of the PUE. Here's my rationale for the above:

Please tell me what is best for the kitchen, if there is an electric stove, dishwasher, microwave, electric kettle, refrigerator. I think I'll divide it into two groups:
1) for electric stove: VVG 4 or 6mm.kv + automatic, RCD is in question
2) for everything else: VVG 4mm.kv + automatic, RCD, I don’t know whether or not.

There is definitely a separate group for the electric stove. If the stove is modern and powerful enough - more than 9 (kW), then lay a cable with a cross-section of 6 sq. mm over copper. RCD optional.

I can’t say about the rest, because... I don’t know the power, maybe 2.5 sq.mm will be enough - that’s up to about 25 (A) or up to 5.5 (kW). Although it can be laid with a margin of 4 sq. mm. RCD is required.

Thank you for the answer, and for the site too, a lot of useful information, chewed to the smallest detail, for me, a half-trained rural electrician, this is a godsend.

Very helpful information. You can quickly become a “Soviet engineer”!
Why owls engineer?

In 1997, he worked in Germany as an illegal immigrant.
They hired me at the stock exchange in Frankfurt am Main. Who was - knows.
They took it upon themselves to clear a certain area of ​​garbage. But it was delayed for several weeks. I had to knock down one wall that was falling apart, build it and plaster it, lay a concrete screed, cover the walls with clapboards, and cover them with tiles in certain places, and do a lot of different work such as electricity, plumbing, etc.
Finally I installed the lamps.
Babi, a German woman, asked me what the Pakistani owner drove.
You were hired to sweep and you did so many different jobs, what is your specialty?
And what do you think, what was the answer?

Hello! Thank you very much for creating a useful and interesting site.
Interesting. If the wiring in an apartment with an electric stove is changed, can the PE conductor for the electric stove be used for common apartment groups?

Valera, it’s possible if it’s really a protective PE conductor. This is checked in the floor (accessible) panel or shaft, where the risers (mains) of electrical wiring are laid: A, B, C, N, PE (5 wires) or A, B, C, PEN (4 wires).

If the PE conductor for the slab was connected to a separate protective PE conductor of the riser, then it can be considered a full-fledged PE, and if it was connected to the combined working PEN conductor of the riser, then your slab was not grounded, but neutralized.

Good afternoon.
All wiring in the apartment is made with aluminum wire.
I want to additionally install a few more sockets and make the wiring to them from copper. I wanted to connect these sockets in parallel with the existing ones
Interested in the following
1.How to make the transition from aluminum to copper
2. Is it necessary to organize “ground” in new sockets (it is planned to connect a TV, computer, iron to these sockets)
Thanks for the answer.

I want to replace the old aluminum wiring in my apartment with new ones, and add sockets in different places! But here's the problem, I can't find where the old wiring is located. Tell me how they usually installed wiring in houses built in the 80s and 90s? They are coming from somewhere from the ceiling. And is it possible to lay new wiring in the channels of reinforced concrete slabs where the old wiring was located?
Our house is a panel house built in 1991!
THX!!!

2 bedroom!

Alexander, I had the same question, but there was no answer, so I figured it out myself. I have the same house, and as the local electricians said, the wires go through the neighbors above. In your apartment you can only find branching boxes, usually located above the switches. In my house in load-bearing walls near the ceiling along the wall there is a channel about 1.5-2 cm in diameter, some of the wires are laid in it, but they will still go somewhere to the neighbors. I did the same: I drilled a hole from the shield into the corridor, laid new wires (though it turned out to be a whole bunch) and routed them through the rooms in the above channels. in order not to make grooves in load-bearing walls, I lowered the wires to the floor level in soft non-load-bearing walls (they can be easily grooved) and laid them under the parquet. spread it all over the apartment. And in the corridor all the wires run along the ceiling, I’ll close it later stretch ceilings. I couldn't think of a better solution. Don’t forget to then draw a diagram of where the wires are laid (with dimensions) so that you don’t accidentally drill them later!

Alexandru 09/16/2013
Why do you need old tracks? Forget about them and aluminum. Everything is being done along new paths.

Andrey 09/17/2013 You can’t go under the parquet - it’s a combustible material.
The wiring diagram is good, but better photo, and put it into your computer as a memory.

Well, you shouldn’t forget about the old tracks at all. Sometimes they are needed. You pull off the old wire and immediately insert a new one. And there is no need to dabble.

Alexandru 10/02/2013
Old tracks are rarely needed. For example, vertical 2m on the wall between the bathroom and toilet in reinforced concrete houses 80-90, or the path inside the panel to the chandelier.
The manner of driving the routes was not mentioned here; personally, I usually lead at vertical and horizontal joints of walls and ceilings - it’s easier there, and all the walls are free for nailing pictures, shelves, and cabinets.
By the way. It is best to document the finished routes on the surface developments of each room. Do you remember developing a cube from school?
And if you take photographs, then first draw distances to landmarks on the walls, imprint dates on the photo (maybe someone can even give you the name of the photo). Otherwise, you can easily get confused in a bunch of photos.

Hello, please tell me what scheme to use for grounding in a wooden 2-apartment building, input from overhead lines with two wires, phase, zero, I plan to replace all the electrical wiring.

I'm leaning towards the TT system

Hello! I want to praise you for a very interesting and useful site - I learn a lot of new things from your articles for myself.
Regarding this article, is the old diagram of your apartment’s power supply correct? gas stoves? According to it, the difference from the first scheme is only in the absence of a PE conductor. The electric stove remained as it was on the diagram. Yes, and in apartments with gas stoves, the introductory machine used to be installed at a maximum of 25A, or even 16A.

For some reason, the author stubbornly puts one machine on all the diagrams for lighting, the other on the sockets, I have never seen this in any apartment - if the light machine turns off, the lights in the entire apartment will go out - walk in the dark. Isn’t it better to make a cross connection, with the condition that in each room the lighting and some of the sockets are powered from different machines?

Alexey 12/26/2013 It’s a pity that so far you haven’t seen normal apartments, where the sockets are powered from some machines, and the lighting from others, and there is no cross-feeding. The author speaks correctly.

Andrey:
Since 2000, reconstruction of electrical networks is carried out according to new standards. All copper wires have a cross-section of 1.5 mm for lighting, and 2.5 mm for sockets.
Wiring in the voids of floor slabs is considered hidden, and hidden electrical wiring. wiring must be replaceable (see PUE). New wiring do it hidden in grooves along the walls in the floor and in the ceiling (along the ceiling, along the floor, followed by pouring and plastering). You can do it openly in boxes and believe me, with the right selection of box elements, it can be done very beautifully. What is easier for you is up to you to decide.

To Vladimir:
You can wire the sockets without boxes, in separate groups. And when installing el. The lighting network requires a minimum of boxes for taps to switches and lamps. It is not allowed to make connections and branches in boxes for mounting switches and sockets, see PUE.

Vitaly:
In old houses, the grounding system is TN-C, i.e. the N and PE wires are combined into a common PEN conductor. According to Chapter 1.7 of the PUE, in this case the PEN conductor can be divided on the body of the floor panel, i.e., take one wire N from the ground busbar, and the other PE from the ground bolt and, of course, the phase conductor and introduce 3 wires into the apartment.
The point is that by doing this we reduce the resistance on the PEN section of the wire for leakage currents.
There may be no circuit, but there should be a grounding source for the ASU at home anyway. But if they don’t find it, then the “earth” still “comes” to the house. The 4th core of the supply cable and its armor are connected to the grounding point of the transformer substation.
You can and should connect an RCD; in any case, this is for the safety of you and your household. Even when there are only two conductors. (see RCD brochure edited by V.K. Monakov).
For email plates, the leakage current setting is 10 mA (see Technical circulars of the Association Ros Electrical Installation).

Sana:
The admin is right. According to the standards for slabs with a power of more than 9 kW (single phase), copper cable (CU) is 6 mm sq. and the circuit breaker in the panel is 40 A, the RCD is 50 A, the cut-off current is 10 mA. Dishwasher, washing machine, jacuzzi, some types of shower cabins are connected into separate groups, i.e. each consumer has its own circuit breaker. For a kettle, microwave, coffee maker, refrigerator - its own group with a cross section of 4 mm square. with a permissible current of 32 A, the automatic is 25A but not more and taking into account Ki - the equipment utilization factor.

I am touched by the video at the end of the article, especially its title “Higher Extreme.” Higher Extreme is the driveway sign in the photo. And I don’t want to believe that 20-30 years ago there were some rules for a while, even though I have a manual from the 80s on electrical installation on my shelf. Is this what you have to be like to build a shed like this? Every time I open something like this ***** I remember all the relatives of the person who did it.

Konstantin, I absolutely agree with you. It’s just scary to be in such shields, by the way, I recently talked about this, like when I changed the meter.

Admin
By the way.
For email plates, the leakage current setting is 10 mA (see Technical circulars of the Association Ros Electrical Installation.
Is the setting too low, taking into account the background leakage of the electric stove?

There will be a water heater and a washing machine in the bathroom. Is it necessary to protect each of them with its own differential circuit breaker or get by with one for the washing machine and the water heater?

Boris 12/03/2014 at 21:11
Better put two for the whole apartment.

In the diagrams, the input wire is 2.5 mm, and the input circuit breaker is 40A - so the wire can burn out even at 40A?

Alexander, please tell me the PUE point where “Making connections and branches in boxes for installing switches and sockets is not allowed”

I bought an apartment in a panel 5-story building. LenBok project. The wiring is accordingly as old as a house from 1978. I was about to make a good repair after entering the 2x4 automatic supply unit (gasified house) and, accordingly, change all the aluminum because... the old one is already burnt out everywhere and is not suitable for modern loads. There will be warm floors. Electric oven. (My wife doesn’t want to get used to a gas oven. And I’m not a fan of the heartburn of burnt pies.) There will also be a PC, stereo, and printer. In general, there will be a new shield. I plan to keep it to 36 places. My wife says why is it so big? They say everyone has two or three machine guns and that’s it. And I know exactly the assembly diagram (I’ve already thought it through) and would be glad to post a post with a photo report upon completion) I apologize for such a large deviation from the main thing))) since ShchR will be introducing a new one in the apartment copper cable I decided to trust the housing department employees. Not because I can't. (I am a 4th category electrician) and because I opened the floor panel. Works with partial withdrawal It is dangerous to conduct voltage there. Lots of dragons. Cobwebs from one and a half sheets. And a lot of bags. I'm allergic to them. In production, I would turn off the riser. But here the distinction no longer allows. And I don’t want to take responsibility. And I don’t advise anyone to work with packet receivers on their own (a very dangerous thing, 50/50 that the outcome will be good. If you’re not sure, don’t interfere! I always try to do complete stress relief where there are no receivers of the first category. All the best, thank you

Denis Mikhailovich
1. Putting electrical systems in order is a noble cause. But the better you want to do, the more big and small problems there will be. I am an expert in identifying and solving such problems. I'll try to describe some of them. First, the more important and difficult ones.
2. Judging by the cross-section of the input wires, the permissible power consumption of your apartment is 5 kW with an input circuit breaker of a maximum of 20A (it’s good if 25A). And the housing office will categorically not allow you to increase this power from the existing riser, with a corresponding increase in the input machine and the cross-section of the input cable. 5 kW is not too much for a modern apartment, so you won’t be able to turn on quite a lot at once. Private residential buildings have a 5 kW limit, ask around how they live.
True, there are a couple of ways to increase this limit. First: if the housing office allows it, you can lay your own cable to the ASU at home. Second: you can lay your own cable even to the TP.
3. The housing office, in theory, may agree to carry out renovations of the apartment under the contract, but will require going through the standard route: obtaining technical conditions, completing the project, all approvals, etc. All this will cost a pretty penny. Therefore, people usually take risks and do everything without the participation of the housing office. For example, I do all this alone, including work on the riser without turning it off. Of course, you will need to be very confident in the qualifications and courage of the electrician, otherwise the matter may end in a major driveway (if not house) accident with a fire and a fatal accident.
4. Most likely, you will have to give up many electrical amenities - heated floors, an electric oven, an electric kettle, and other powerful consumers. It is possible that it will turn out that even connecting an automatic washing machine will require a separate permit. Or install a load priority relay. In general, you ended up in a house for not too rich people.
On other less important and complex problems you mentioned.
5.The spouse will have to learn to make do with less. electrical power. You will have to explain to her the convenience of having a large number of power lines and complex and expensive protection.
6. It’s good that you are an electrician. But I assume that your production experience will not be of much use to you in your repairs - the approach to electrics in production and in your apartment is too different.
7. It would be useful for you to tell us about the power supply plan for your apartment; you will be given a lot of the most contradictory recommendations. I myself have extensively splurged on this topic on this site many times, we can try it with you. You just won’t be able to post a diagram and a photo; you’ll have to explain everything in words.

For (elalex) you can always come to an agreement with the Zhekovskys. And the opening machine is not a problem. outside it's 25A and inside it's 60A. And the option with your own cable isn't bad either. The liar is on the first floor and I'm on the second. So the length is not great. Well, as an experienced installer, there will always be materials available. Only in Surgut I can’t find an RKN for phase voltage

Denis Mikhailovich 02/21/2015 at 16:41
1. Of course, it can be negotiated with the housing office, but for how much and at what level. But with overloaded cables and angry neighbors during an accident, I don’t know. And the machine can be imperceptibly counterfeited, but you can’t hide an awl in a bag - the neighbors will see the thick cables, their low voltage and draw conclusions. I had a case, in a new house one rich tenant managed to take away the electricity from the entire entrance, there was a scandal, he had to run his cable from the street.
2. I wonder, what about the RCD in Surgut? Do you have online stores? In theory, now it shouldn’t matter where you live.

House ii-68-01, built in 1974, 16 floors, with slabs. On our panel (corridor panel) in the diagram there is a grounding wire (the one from the first paragraph). Now the actual questions:
1) Where exactly is the ground wire located? If not a wire, then probably a special fitting that goes into the ground under the foundation?
2) Is it possible in the future to power the equipment to ground the stove? Now only the stove is (sort of) grounded, but the rest is not.

To the motorbiker 09.15.2015 at 23:54
1. Scheme in the corridor panel - Filkina's diploma, don't pay much attention to her.
2. Don’t look for the grounding wire (grounding conductor) going into the ground - you won’t find it. You will work with the wires that are in the corridor panel.
3. There must be a protective conductor to the stove; in the same way, the rest of the apartment must be protected.
4. Take a photo of the open corridor panel and post it on the forum http://forum-electrikov.ru/ in the “Design of internal power supply” section, come up with your own topic, for example, “Protective wiring for an apartment.”

Motorbiker: it’s exactly the same in my 16-story building, but there is no separate grounding wire, there is a common connection point between the entire frame of the house and the grounding loop, which is meant “somewhere there” and the zero of the three-phase line from 1st to 8th, and from 9th to 16th floor. The slabs of all apartments are “grounded” by the middle conductor of an aluminum three-core 3x6 sq. mm to the same common point in the panel and that’s it. Just to the point of snot.
And by the way, everything in the dashboard was done strictly according to the scheme at first, I’ll find it and show you. Then the atrocities of everyone who was both lazy and not lazy began.

for surfactants 09/16/2015 at 13:54
1.You seem to be a radio engineer? There may not be a common point of connection between the entire frame of the house and the ground loop, as well as the loop itself. The grounding may be the foundation itself.
2. In the panel room of the house, the incoming neutral wire is grounded and then goes along the risers as a PEN - both working and protective. In floor panels, PEN sits on their bodies and is distributed onto apartment slabs (TN-C system). Actually, this is not “grounding”, but grounding. If it’s bad for one point in the floor panel, each wire needs its own screw. In radio engineering, everything can be done with one screw.
3.Dangerous voltage will appear on the PEN if the zero is broken.
In my opinion, it’s not as simple as snot. You need to think and understand.

What does radio technology have to do with it, is there nothing else to cling to?
Once again, as for an electrician, what was in the house and is almost preserved: floor panels are welded to the fittings sticking out of concrete wall, at these points the zero of the three-phase line is connected to the point of connection of the fittings to the switchboard by means of compression. All “grounding” wires for the slabs are placed on the panel next to the apartment post-metering machines and cannot be switched off.
Each apartment is powered through an automatic circuit breaker that disconnects both the line and neutral wires.
The zeros of the sockets and lighting are connected on a terminal block insulated from the metal of the shield with the zero after the meter.
What is there under the house - guess for yourself.

For surfactants 09/16/2015 at 22:08
1.Radio engineering despite the fact that it has a detrimental effect on electrical knowledge and skills. There is a user on the site called kolka, he does not hire anyone who has at least some electrical knowledge and skills. There is a certain logic in his policy: retraining is more difficult than teaching. You even use the terminology of a non-electrician.
2. There is always something to cling to. I guarantee that I will find several gross errors in the apartment after any team of electricians.
3. If your floor panel housings are welded to grounded fittings, this is wonderful.
4. Electricians don’t say “grounding wires.” They say “protective conductors”, connected to a protective zero or grounding - the second question.

Tell
We need to replace the entire electrical system. wiring in an old apartment, the old wiring is 3-phase, is it better to leave 3-phase or convert it to 1-phase, what I mean is: phase imbalance (if 1-phase) if you scatter the phases into groups, there is still a distortion (not all phases will load evenly, summer-winter, spring-autumn)?
Here's another diagram: two one-room apartments hang on one entrance machine, and two two-room ones on their different entrances, so how can we divide the PEN into different ones?

Zheke. Answers.
1. 3 phases are 380 volts. I highly doubt that your apartment, no matter how old it is, has 380 volts. This is not an industrial facility. Let's start with something simple: what is the meter worth? Three-phase? If yes, then you need to leave the circuit as three-phase, otherwise they simply won’t register it for you. But I doubt it.
Now let's move on. If, after all, you have a three-phase load (maybe there is such a miracle after all), then the calculation of the phases should be done by a specialist and issued a certain project; you are strictly forbidden to go there yourself.
2. PEN has nothing to do with introductory machines and the number of phases, it is the same everywhere: even ten apartments, even three; use any switching scheme. Remember - there is only one PEN.

Moreover, in an old apartment! Where are the 3 phases from?

Hello! Thank you for such an informative site. I've been reading it for a day now. You can get the opinion of experts. I bought an apartment in an old building. Here the relatively old wiring lies under the baseboard. More precisely, there are no baseboards, but there is wiring. The sockets themselves are 20cm from the floor - the cable is in a groove. I want to change the wiring, add sockets and so on. The doctor is asking this - is it possible to do the same? the easy way and use skirting boards with cable duct? The apartment is small, there won't be many outlets. The cable is 2.5, of course... I don’t want to make a mess again, but the baseboards with the channel are beautiful))) I’m really looking forward to your answer!

Tatyana, quite. This is called open wiring and it is not prohibited by the Rules. Now there are special plinth cable ducts made of plastic, look at the catalogs of the same DKS, Legrand or Hager. They look decent and install quickly. Also among them you can choose different colors: white, black, wood, etc. By the way, some baseboard cable channels allow you to install sockets and switches directly into them, i.e. there is no need to make a cable outlet into the wall socket, and a socket or switch is installed directly into the baseboard - very convenient, and it looks beautiful and monolithic. In general, there are many options, look in the catalogs.

Good afternoon. How does the overhead light fit into an old apartment? I have a triple switch next to my bathtub and toilet. There seems to be a transformer in it even lower. Which, as my current relatives say, never worked. He paused. The overhead lights went out everywhere. The machine seems to be working. I turned it on and off. The light didn't appear. Could there be a junction box in this switch for the entire overhead light?

Alexey, who can know about your apartment, its wiring, the mysterious transformer, without even looking, in absentia? It’s unlikely that there are shamans here, I haven’t met them yet.

Hello. In the floor board, the management company got clever with the connection diagram for apartment zeros. How can this affect the accuracy of meter readings? And why? After reworking the scheme for one apartment, meter consumption dropped sharply.

Even this is how it was. Corrected in red. All apartments are connected like this.

Nikolay, basically all single-phase meters record only by phase, i.e. control the current flowing through the terminal (1-2). And therefore, if the initial connection diagram of the zeros is not accurate, this will not affect the readings in any way. A decrease in consumption in one of the apartments may be an elementary coincidence - it needs to be analyzed. By how much exactly did it decrease, 2 times or more? What type of meter is installed in this apartment? Have the consumers in this apartment changed? Has your electricity consumption changed? And so on.

Thank you for your reply.
PU Neva 101, the subscriber says that he checked with a water heater. Before the alteration, 40 kW per day, after - 15. But here I also have doubts; not using anything for a day is almost impossible. I thought the same with zeros. Yes, before the alteration, we measured the load with clamps at the phase and zero loads - the readings are different. At zero the load did not show at all.

Dmitry, but what if it’s on NP71L. It shows the date incorrectly, but the total consumption will still be shown for the current day? Is a date needed to take readings remotely? Correct me if I'm wrong.