DIY electrical circuit repair

Each person forms his own circle of contacts, and it so happened to me that in contact and in real life I am mainly surrounded by people who have this or that relation to technology. It happens that sometimes a person writes to Vkontakte and asks for help to repair a device. You answer in the standard way that you have already called on the board and you hear in response that he doesn’t know how to do it, but you really need to direct the device).

Checking radio components with a multimeter on the board

You can, of course, send a person to teach a textbook of physics, electrical engineering, google on sites devoted to electronics, saying that you are too hard to cut a branch, but decided to try to reveal some of the nuances of repairs for all these people who apparently skipped or sat through physics lessons and electrical engineers, and now suddenly decided to catch up. Remembering that electronics engineers are not born, but become.

Measuring DC current with a tester

So, we have a multimeter and with it you can measure various quantities, for example, such as current, alternating and direct, which we do not need for repairs as often as other quantities. Although there are test points on the diagrams at which you need to break the circuit and measure current currents or voltages. In such cases, it is indicated directly on the diagram what voltage or current should be present at this point.

Test point measuring current on the diagram

We measure the voltage on the board much more often than currents, because if there is no voltage in the circuit, for example, on the power connector, then this is a clear sign that the circuit is not functioning correctly. These measurements are referred to as hot or no-power measurements and must be performed with normal electrical safety precautions. Since on boards, for example, switching power supplies, in some parts of the circuit, we have high voltage. Other measurements, in particular resistance measurements or sound continuity measurements, are carried out only in a de-energized device!

This is an important rule, it is enough to make a mistake once and measure the resistance instead of voltage, or the same on the audio continuity, and at best you will have to look for a circuit for a multimeter and change resistors, which most often come in a planar case and have small dimensions, for example 0805 or even 0603. In the worst case, you will burn the ADC of the device - that very black drop, and the device will not be subject to repair, or its repair will be at least unprofitable.

Multimeter ADC IC

When we measure the voltage on the board in an unfamiliar place without knowing exactly what value we should have, always set a higher value on the multimeter. For example, if the power supply gives out 35 volts and measure at the output, choose 200 volts, if 5 volts, then 20 volts. The same is with the resistance: if the resistor is marked not with colored rings, but for example of the MLT type and it is impossible to decipher the marking, select the 2 MegaOhm mode on the multimeter, followed by a decrease in the measurement limit to ensure the required accuracy.

Always when repairing switching power supplies that have in their circuit, for example, electrolytic capacitors for a voltage of 400 - 450 volts and a nominal value of 100 - 150 microfarads, discharge the capacitor by shorting the terminals together with a screwdriver with an insulated handle. The same applies to the repair of ATX power supplies - there the voltage of electrolytic capacitors is less, only 200 volts, but it must be admitted that the tingling is not weak anyway.

CRT board

Sometimes, for example, on the boards of CRT TVs, there are several such capacitors with a high operating voltage, and not just one filter capacitor. They are usually somewhat smaller than the filter capacitor. What is the basis for checking radio components, using an ohmmeter, and sound dialing? Let's recall Ohm's law: the lower the resistance at a constant voltage, the greater the current.

If suddenly the resistance of one part suddenly becomes very small, then according to Ohm's law in the section of that circuit, currents will flow that greatly exceed the permissible ones, for example, resistors may not like it a lot - they will overheat, turn black, and in especially severe cases even burn out ... This fully applies to any semiconductor.

Maximum graphics card temperature

We all know, for example, by the thermal profile of video cards, that the temperature of the order of 75 - 85 degrees is usually the limit for silicon, during prolonged operation, and the video card eventually gives out artifacts, and for example, the chipset on the motherboard begins to heat up abnormally, and as a result, in In the best case, the computer will not work stably, and in the worst case, it will not turn on at all. So, transistors and diodes, like any microcircuits, are all the same semiconductors, which will simply burn out when excess currents and an increase in temperature appear.

Burnt resistor is normal

How can you determine that a part has burned out using a multimeter? Resistors very often go into an open circuit during combustion, if the resistor does not ring even at the limit of two Megaohms - most likely it burned out. What does a resistor burn out from a physical point of view? This means that he has a very large resistance between the terminals, and if so, then, according to Ohm's law, microscopic currents conditionally flow there. Which can be considered an open circuit. Any semiconductors, on the contrary, very often go into a short circuit or low resistance, but this is not always the case. Why this parameter, the resistance of the radio component is so important for the operation of the circuit, we have disassembled.

Planar resistor

Now we can in general, in principle, evaluate any object from the point of view of its conductivity for an electric current. Let us examine, for example, such a situation - why a TV brought from the garage from the cold cannot be immediately connected to the network, but you need to let it stand for 30-40 minutes in the warmth, and let the temperatures even out.

The fact is that droplets of water can form on the terminals of radio components, from frost, and water is a good conductor and resistance between closely spaced terminals of a microcircuit containing, for example, a power transistor that turns on the device, it turns out to be closed, two or even all three terminals , transistor or microcircuit, among themselves. What does this lead to?

The designation of the terminals of the transistor

Those pins of the microcircuit or, for example, the base terminal of the transistor, they are connected to the low-voltage part of this device, and the supply of high voltage to them will lead to their obligatory breakdown, a decrease in resistance, or even a short circuit, and at the same time they can take with them any other parts on scheme. For what purpose is it necessary to regularly clean the dust from the circuit boards of the device? The first is dust, this is a heat insulator, it interferes with the removal of heat from radio components, which heat up during operation, their temperature rises and they fail.

The second reason is dust on the board between the terminals, this is certainly not a conductor, but it cannot be said that it is a very good insulator. Under normal conditions, it may not break through dust, but after bringing in equipment from frost - everything can be, because dust saturated with moisture has a lower resistance than dry dust, and it dries, most likely, longer than just a little frost on the board.

Switching power supply board

Knowing how to analyze a circuit and a printed circuit board, you will know what is the approximate resistance, in total, of all parallel-connected parts, should be at one point or another.Even when we ring non-semiconductors with a multimeter on a sound continuity, we measure the same resistance between certain parts of the circuit.

Sound Continuity of the Multimeter

If we hear a sound signal, then the resistance between the points at which we are measuring is lower than 50 Ohm, the numbers are of course approximate, but I think the principle is clear. Knowing what resistance this or that part has in the working and in the non-working state, we can analyze the device for operability without having a schematic diagram. With the scheme, of course, everything is much simpler, but there is a technique, for example, little-known Chinese brands, for which you will not find schemes anywhere. In this case, only the analysis of the operation of the circuit, the principle of its operation, experience in working with similar circuits, or the search for an analogue of our circuit, albeit with other reference designations on the diagram, will help us.

Positional designation on the diagram and rating

In this case, you will need to track each node along the paths, but this is certainly better than the absence of any documentation at all.

The purpose of writing this article is to show novice electrical engineers that knowledge of the basics of repairing equipment is not only interesting, but also in our financially difficult time, can help radio amateurs and electronics engineers, save some of the money on self-repair. And in the future, as you level up, you will regularly earn extra money in this area. This is now becoming especially important, since people now more and more often turn to for repairs, and not just throw away the old and buy new household appliances, as before. Successful repairs to everyone! AKV.

In the life of every home craftsman who knows how to hold a soldering iron in his hands and use a multimeter, there comes a moment when some complex electronic equipment breaks down and he has to make a choice: take it to a service for repair or try to repair it on his own. In this article, we will break down the techniques that can help him with this.

So, you have broken any equipment, for example LCD TV, where do you need to start repairs? All craftsmen know that it is necessary to start repairs not with measurements, or even immediately re-soldering the part that aroused suspicion of something, but with an external examination. This includes not only inspecting the appearance of the TV boards, removing its cover, for burnt radio components, listening in order to hear a high-frequency squeak or clicking.

To begin with, you just need to turn on the TV to the network and see: how it behaves after turning it on, does it respond to the power button, or the standby LED blinks, or the image appears for a few seconds and disappears, or there is an image, but there is no sound, or vice versa. By all these signs, you can get information from which you can push off with further repairs. For example, in the blinking of the LED, at a certain frequency, you can set a breakdown code, self-test of the TV.

TV error codes by flashing LED

After the signs are installed, you should look for a schematic diagram of the device, or better if a Service manual for the device is released, documentation with a diagram and a list of parts, on special sites dedicated to electronics repair. It is also not superfluous, it will be in the future, to drive into the search engine the full name of the model, with a brief description of the breakdown, conveying in a few words its meaning.

True, sometimes it is better to look for a diagram by the device chassis, or by the name of the board, for example, a TV power supply. But what if the circuit still could not be found, and you are not familiar with the circuitry of this device?

In this case, you can try to ask for help on specialized forums for the repair of equipment, after carrying out preliminary diagnostics on your own, in order to collect information from which the masters who help you can push off.What stages does this preliminary diagnosis include? To begin with, you must make sure that power is being supplied to the board, if the device shows no signs of life at all. It may seem trivial, but it will not be superfluous to ring the power cord for integrity, in the audio dial mode. Read here how to use a regular multimeter.

Tester in the mode of sound dialing

Then the fuse is ringing, in the same multimeter mode. If everything is fine with us here, you should measure the voltages at the power connectors going to the TV control board. Typically, the supply voltages present on the connector pins are labeled next to the connector on the board.

TV control board power connector

So, we measured and we do not have any voltage on the connector - this indicates that the circuit is not functioning correctly, and we need to look for the reason for this. The most common cause of breakdowns found in LCD TV is banal electrolytic capacitors, with an overestimated ESR, equivalent series resistance. Read more about ESR here.

Capacitor ESR Table

At the beginning of the article, I wrote about the squeak that you may hear, and so, its manifestation, in particular, is a consequence of the overstated ESR of small capacitors standing in the standby voltage circuits. To identify such capacitors, a special device is required, an ESR meter, or a transistor tester, although in the latter case, the capacitors will have to be soldered for measurement. A photo of my ESR meter that allows you to measure this parameter without soldering is posted below.

What if such devices are not available, and suspicion fell on these capacitors? Then you will need to consult on the repair forums, and clarify in which node, which part of the board, the capacitors should be replaced with obviously working ones, and only new (!) Capacitors from the radio store can be considered as such, because used ones have this parameter, ESR may also be off scale or already on the verge.

Photo - swollen capacitor

The fact that you could remove them from a device that previously worked does not matter in this case, since this parameter is only important for working in high-frequency circuits, respectively, earlier, in low-frequency circuits, in another device, this capacitor could function perfectly, but have an ESR parameter that is highly off-scale. The work is greatly facilitated by the fact that capacitors of a large denomination have a notch in their upper part, along which, if they become unusable, they simply open, or a swelling forms, a characteristic sign of their unsuitability for any, even a novice master.

Multimeter in Ohmmeter Mode

If you see blackened resistors, you will need to ring them with a multimeter in ohmmeter mode. First, you should select the 2 MΩ mode, if the screen shows values ​​that differ from one, or the measurement limit is exceeded, we should accordingly reduce the measurement limit on the multimeter to establish its more accurate value. If there is a unity on the screen, then most likely such a resistor is in an open circuit, and it should be replaced.

Resistor color coding

If it is possible to read its denomination, according to the marking with colored rings applied to its case, it is good, otherwise, one cannot do without a diagram. If the circuit is available, then you need to look at its designation, and set its rating and power. If the resistor is precision, its (exact) value can be dialed by connecting two ordinary resistors in series, larger and smaller, the first we set the value roughly, the last we adjust the accuracy, and their total resistance will add up.

Transistors are different in the photo

Transistors, diodes and microcircuits: it is not always possible to determine the malfunction by their appearance. A measurement with a multimeter is required in the audible dial mode.If the resistance of any of the legs, relative to some other leg, of one device is zero, or close to it, in the range from zero to 20-30 ohms, most likely such a part must be replaced. If this is a bipolar transistor, you need to call in accordance with the pinout, its p-n junctions.

Checking the transistor with a multimeter

Most often, such a check is enough to consider the transistor as working. A better method is described here. In diodes, we also cause a p-n junction, in the forward direction, there should be numbers of the order of 500-700 when measured, in the opposite direction, one. The exception is Schottky diodes, they have a lower voltage drop, and when dialing in the forward direction, the screen will display numbers in the range 150-200, in the opposite direction there is also one. Mosfets, field-effect transistors, it is not possible to check with an ordinary multimeter without soldering, it is often necessary to consider them conditionally working if their outputs do not ring among themselves shortly, or in low resistance.

Mosfet in SMD and regular case

In this case, it should be borne in mind that the mosfets between the Stock and the Source have a built-in diode, and when dialing, there will be readings of 600-1600. But there is one nuance here: if, for example, you ring the mosfets on the motherboard and hear a sound signal at the first touch, do not rush to record the mosfet in the broken one. In its circuits, there are electrolytic filter capacitors, which, at the moment of the start of charging, as you know, for some time behave as if the circuit is short-circuited.

Mosfets on the PC motherboard

This is what our multimeter shows, in the mode of sound dialing, squeaking, for the first 2-3 seconds, and then increasing numbers will run on the screen, and the unit will be set as the capacitors charge. By the way, for the same reason, in order to save diodes of the diode bridge, a thermistor is installed in the switching power supplies, limiting the charging currents of electrolytic capacitors, at the moment of switching on, through the diode bridge.

Many acquaintances of novice repairmen who apply for remote consultation in, are shocked - you tell them to ring the diode, they will ring and immediately say: it is punctured. Here, as a standard, the explanation always begins that you need to either raise, remove one leg of the diode, and repeat the measurement, or analyze the circuit and the board, for the presence of parallel-connected parts, in low resistance. These are often the secondary windings of a pulse transformer, which are just connected in parallel with the terminals of the diode assembly, or in other words, a double diode.

Parallel and series connection of resistors

Here it is best to remember once, the rule of such connections:

1. When two or more parts are connected in series, their total resistance will be greater than the greater each, separately.
2. And with a parallel connection, the resistance will be less than that of each part. Accordingly, our transformer winding, which has a resistance of 20-30 Ohm at best, by shunting, imitates a “punctured” diode assembly for us.

Of course, unfortunately, it is not realistic to reveal all the nuances of repairs in one article. For preliminary diagnostics of most breakdowns, as it turned out, a conventional multimeter used in the modes of a voltmeter, ohmmeter, and sound continuity is sufficient. Often, if you have experience, in the event of a simple breakdown, and the subsequent replacement of parts, this is where the repair is completed, even without the presence of a circuit, carried out by the so-called “scientific poke method”. Which of course is not entirely correct, but as practice shows, it works, and, fortunately, not at all as shown in the picture above). Successful repairs to everyone, especially for the site of the Radiocircuit - AKV.

This regulator allows you to smoothly adjust variable resistor fan speed.

The floor fan speed regulator circuit turned out to be the simplest. To fit into the body from an old Nokia phone charger.Terminals from an ordinary electrical outlet also fit in there.

The installation is quite tight, but this was due to the size of the case ..

DIY lighting for plants

There is a problem in the lack of lighting plants, flowers or seedlings, and there is a need for artificial light for them, and this is the kind of light we can provide on LEDs do it yourself.

It all started with the fact that after I installed halogen lamps for lighting at home. When turned on, which often burned out. Sometimes even 1 light bulb a day. Therefore, I decided to make a smooth switching on of the lighting based on the dimmer with my own hands, and I am attaching the dimmer circuit.

DIY refrigerator thermostat

It all started with the fact that after returning from work and opening the refrigerator, he found it warm. Turning the thermostat knob did not help - the cold did not appear. Therefore, I decided not to buy a new unit, which is also rare, but to make an electronic thermostat myself on the ATtiny85. With the original thermostat, the difference is that the temperature sensor is on the shelf and not hidden in the wall. In addition, 2 LEDs have appeared - they signal that the unit is turned on or the temperature is above the upper threshold.

DIY soil moisture sensor

This device can be used for automatic watering in greenhouses, flower greenhouses, flower beds and indoor plants. Below is a diagram by which you can make the simplest sensor (detector) of moisture (or dryness) of the soil with your own hands. When the soil dries up, a voltage is supplied with a current strength of up to 90mA, which is quite enough, turn on the relay.

It is also suitable for automatically turning on drip irrigation to avoid excess moisture.

Fluorescent lamp power circuit.

Often, when energy-saving lamps fail, the power circuit burns out in it, and not the lamp itself. As known, LDS with burned-out filaments, it is necessary to supply with rectified mains current using a starless starter device. In this case, the filaments of the lamp are shunted with a jumper and to which a high voltage is applied to turn on the lamp. There is an instant cold ignition of the lamp, a sharp increase in voltage across it, when starting without preheating the electrodes. In this article we will look at do-it-yourself lds lamp start-up.

Somehow, suddenly, I took something and decided to buy a new keyboard for my PC. The desire for novelty cannot be overcome. Changed the background color from white to black, and the color of the letters from red-black to white. A week later, the desire for novelty naturally went like water into sand (an old friend is better than two new ones) and the new thing was sent to the closet for storage - until better times. And so they came for her, did not even imagine that it would happen so quickly. And therefore the name would be even better suited not which is, but how to connect a usb keyboard to a tablet.

DIY clock on IN-14 lamps

I have long wanted to post an article on manufacturing do-it-yourself clock on IN-14 lamps, or how else, steam-punk-style watches respond.

I will try to outline only the most important things step by step and dwelling on the key points. The clock indication is clearly visible both during the day and at night, and by themselves they look very beautiful, especially in a good wooden case.

DIY street photo relay

This scheme is intended for automatic flashlight activation street lighting at night. The basis of the photo relay is the KR544UD1B microcircuit.

The circuit is assembled from widely available radio components that can be found in every radio amateur.

Smoothly turning on the incandescent lamp with your own hands.

In the course of the incessant burnout of incandescent lamps, including on the staircase, several schemes for protecting incandescent lamps on the Internet were implemented. Their use has yielded a positive result - lamps have to be changed much less often.However, not all implemented device schemes worked "as is" - in the process of operation it was necessary to select the optimal set of elements. In parallel, a search was made for other interesting schemes. As known, smooth switching on of incandescent lamps increases their service life and eliminates inrush currents and network noise. In a device that implements such a mode, it is convenient to use powerful field-effect switching transistors. Among them, you can choose high-voltage ones, with an operating voltage at the drain of at least 300 V and a channel resistance of no more than 1 Ohm.

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Instructions for assembling time relays based on the NE 555 timer and on transistors. Learn how to make a simple DIY time relay.

Learn how to make a simple DIY dimmer. In the article, we have provided assembly diagrams with a detailed description of the manufacture of a dimmer.

If you don't have a boiler at hand, but you need to heat the water, you can assemble a homemade product from available tools. We have provided assembly instructions in this article!

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Not sure how to assemble a simple wind generator from available tools? For you, we have provided some simple ideas for homemade wind turbines.

Find out how to make the simplest projector for your phone and laptop out of handy tools! For you, we have provided step-by-step instructions with photos and videos!

Making an electric heater for your home or car is quite simple! We have provided assembly instructions in the article!

The best homemade garland assembling workshops!

The control light is one of the essential tools of an electrician. How to make it yourself, read here!

Making a simple welding machine at home is not at all difficult. You can be convinced of this by looking at 2 detailed instructions!

An instruction with photo and video examples that will teach you how to independently make a perpetual motion machine from scrap materials.

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The laser level will allow you to smoothly draw the strobe when wiring. Read about how to make a simple level from scrap materials here!

A soldering iron should always be at hand with an electrician.A few simple instructions for building a DIY tool are provided here!

Want to do something simple and useful? We recommend that you look at the photo instructions for assembling a mini drill at home!

Since you have decided to become a self-taught electrician, then surely after a short period of time you will want to make some useful electrical appliance for your home, car or summer cottage with your own hands. At the same time, homemade products can be useful not only in everyday life, but also made for sale, for example, a homemade battery charger. In fact, the process of assembling simple devices at home is not difficult. You just need to be able to read the diagrams and use the tool for radio amateurs.

As for the first point, before you start making electronic homemade products with your own hands, you need to learn how to read electrical circuits. In this case, our brief overview of all the symbols on electrical circuits will be a good helper.

From tools for novice electricians, a soldering iron, a set of screwdrivers, pliers and a multimeter will come in handy. Some popular electrical appliances may even require a welding machine to assemble, but this is a rare case. By the way, in this section of the site, we even told how to make a simple do-it-yourself soldering iron and the same welding machine.

Special attention should be paid to the materials at hand, from which every newbie electrician can make elementary electronic homemade products with his own hands. Most often, old domestic parts are used in the manufacture of simple and useful electrical appliances: transformers, amplifiers, wires, etc. In most cases, it is enough for novice radio amateurs and electricians to look for all the necessary tools in the garage or shed in the country.

When everything is ready - the tools are assembled, the spare parts are found and the minimum knowledge is obtained, you can proceed to the assembly of amateur electronic homemade products at home. This is where our small guide will help you. Each provided instruction includes not only a detailed description of each of the stages of creating electrical appliances, but is also accompanied by photo examples, diagrams, as well as video lessons that clearly show the entire manufacturing process. If you do not understand at some point, then you can clarify it under the entry in the comments. Our experts will try to advise you in a timely manner!

Finally, I would like to note - if you know how to create some interesting electrical appliance with your own hands, and want to share your experience, you can send your own instructions to us by mail via the Feedback form. In turn, we promise to keep the authorship for you so that other visitors know whose electronic homemade product it is!

Technological progress is transforming our streets and houses, changing the style of communication, regulating the style of behavior, and filling the world around with a huge amount of various electronics. The widespread popularization of the Internet made it impossible to have at least one computer in every family. Over time, electronic circuits and entire devices fail and become ordinary junk that cannot be repaired or restored. But even in this case, you can benefit from the failed equipment, enriching the interior with another craft. Our section "DIY electronics"Is dedicated to the manufacture of homemade products from non-working household appliances, as well as the creation of all kinds of electrical devices using improvised means.

We will tell you about the production of a mini-battery at home, and also demonstrate how you can make a table by installing an LCD screen from a TV or monitor into it, or replace a cassette audio system in a car with a built-in computer.On the pages of our section, you will learn how to make an LED stand and decorations for the New Year's Eve with LED elements inside.

Most of the homemade products from this section will appeal to the representatives of the strong half of humanity. Those who like to delve into technology will find an outlet for themselves on the pages of Samodelkin. If you understand electronics at a sufficient level, the creation of the masterpieces presented on the site will not be difficult and will help you to usefully spend one of the long winter evenings. The most important thing is to have patience and the necessary components. The process of creating electronic and electrical appliances requires maintaining safety measures and careful handling of electricity. Therefore, we strongly recommend not only to be present, but also to actively participate in the creation of any crafts from this section that interested your children.

If you have your own experience in the field of creating various electrical crafts, we will be happy to share your detailed reviews with our many visitors. Send your options for homemade products using electronics, detailed photos and video instructions, and we will immediately publish your ideas in the vastness of our portal.

Or enter the site if you are already registered.

Even 15 - 20 years ago, the load on the power grid was relatively small, but today the presence of a large number of household appliances has provoked an increase in loads at times. Old wires are far from always able to withstand a heavy load and over time there is a need to replace them. Laying electrical wiring in a house or apartment is a matter that requires certain knowledge and skills from the master. First of all, this concerns knowledge of the rules for wiring wiring, the ability to read and create wiring diagrams, as well as wiring skills. Of course, you can do the wiring with your own hands, but for this you must adhere to the rules and recommendations set out below.

All construction activities and building materials are strictly regulated by a set of rules and requirements - SNiP and GOST. As for the installation of electrical wiring and everything related to electricity, you should pay attention to the Rules for the Arrangement of Electrical Installations (abbreviated as PUE). This document prescribes what and how to do when working with electrical equipment. And if we want to lay electrical wiring, then we need to study it, especially the part that relates to the installation and selection of electrical equipment. Below are the basic rules to follow when installing electrical wiring in a house or apartment:

Wiring work begins with the creation of a project and a wiring diagram. This document is the basis for future house wiring. The creation of a project and a scheme is quite a serious matter and it is better to entrust it to experienced specialists. The reason is simple - the safety of those living in the house or apartment depends on it. Services to create a project will cost a certain amount, but it's worth it.

Those who are used to doing everything with their own hands will have to, adhering to the above rules, as well as having studied the basics of electrical engineering, independently make a drawing and calculations for network loads. There are no particular difficulties in this, especially if there is at least some understanding of what an electric current is, and what are the consequences of careless handling of it. The first thing you need is a legend. They are shown in the photo below:

Using them, we make a drawing of the apartment and outline the lighting points, installation locations for switches and sockets. How many and where they are installed is described above in the rules. The main task of such a scheme is to indicate the place of installation of devices and wiring. When creating a wiring diagram, it is important to think in advance where, how much and what kind of household appliances will be.

The next step in creating a diagram will be the wiring to the connection points on the diagram.It is necessary to dwell on this point in more detail. The reason is in the type of wiring and connection. There are several such types in total - parallel, sequential and mixed. The latter is the most attractive due to the economical use of materials and maximum efficiency. To facilitate the laying of wires, all connection points are divided into several groups:

• lighting of the kitchen, corridor and living rooms;
• toilet and bathroom lighting;
• power supply of outlets in living rooms and corridor;
• power supply to kitchen sockets;
• power supply of the socket for the electric stove.

The above example is just one of many lighting group options. The main thing to understand is that if you group the connection points, the amount of materials used is reduced and the circuit itself is simplified.

Important! To simplify wiring to the outlets, the wires can be tucked under the floor. Overhead lighting wires are laid inside the floor slabs. These two methods are good to use if you don't want to gouge walls. In the diagram, such wiring is marked with a dotted line.

Also in the wiring project, the calculation of the estimated current strength in the network and the materials used are indicated. The calculation is performed according to the formula:

where P is the total power of all used devices (Watt), U is the voltage in the network (Volts).

For example, a kettle of 2 kW, 10 bulbs of 60 W each, a microwave oven of 1 kW, a refrigerator of 400 W. The current strength is 220 volts. As a result (2000+ (10x60) + 1000 + 400) / 220 = 16.5 Amperes.

In practice, the current in the network for modern apartments rarely exceeds 25 A. Based on this, all materials are selected. First of all, this concerns the cross-section of the wiring. To facilitate the selection, the table below shows the main parameters of the wire and cable:

The table shows the most accurate values, and since quite often the current strength can fluctuate, a small margin will be required for the wire or cable itself. Therefore, it is recommended that all wiring in an apartment or house be made of the following materials:

• VVG-5 * 6 wire (five cores and a cross-section of 6 mm2) is used in houses with three-phase power supply to connect the lighting panel to the main panel;
• VVG-2 * 6 wire (two cores and a cross-section of 6 mm2) is used in houses with a two-phase power supply to connect the lighting panel to the main panel;
• VVG-3 * 2.5 wire (three cores and a cross-section of 2.5 mm2) is used for most of the wiring from the lighting panel to junction boxes and from them to sockets;
• VVG-3 * 1.5 wire (three cores and a cross-section of 1.5 mm2) is used for wiring from junction boxes to lighting points and switches;
• VVG-3 * 4 wire (three cores and a cross-section of 4 mm2) is used for electric stoves.

To find out the exact length of the wire, you will have to run a little with a tape measure around the house, and add another 3-4 meters of stock to the result obtained. All wires are connected to the lighting panel, which is installed at the entrance. Circuit breakers are mounted in the shield. Usually these are RCDs for 16 A and 20 A. The former are used for lighting and switches, the latter for sockets. For the electric stove, a separate RCD of 32 A is installed, but if the power of the stove exceeds 7 kW, then an RCD of 63 A.

Now you need to calculate how many sockets and junction boxes are needed. Everything is pretty simple here. It is enough to look at the diagram and make a simple calculation. In addition to the materials described above, various consumables will be required, such as electrical tape and PPE caps for connecting wires, as well as pipes, cable ducts or boxes for electrical wiring, and socket outlets.

There is nothing super complicated in wiring work. The main thing during installation is to adhere to safety rules and follow the instructions. All work can be done alone. From the installation tool, you will need a tester, a hammer drill or grinder, a drill or screwdriver, wire cutters, pliers, and a Phillips and slotted screwdrivers. The laser level will not be superfluous.Since without it it is quite difficult to make vertical and horizontal markings.

Important! When carrying out repairs with the replacement of wiring in an old house or apartment with hidden wiring, you must first find and, if necessary, remove the old wires. For these purposes, a wiring sensor is used.

We start the installation with the markup. To do this, using a marker or pencil, we put a mark on the wall where the wire will be laid. At the same time, we observe the rules for placing wires. The next step is to mark the places for the installation of lighting fixtures, sockets and switches and a lighting panel.

Important! In new houses, a special niche is provided for the lighting panel. In old ones, such a shield is simply hung on the wall.

Having finished with the markings, we proceed either to the installation of the wiring in an open way, or to the chipping of the walls for hidden wiring. First, using a perforator and a special crown nozzle, holes are cut out for the installation of sockets, switches and junction boxes. For the wires themselves, grooves are made using a grinder or a perforator. In any case, there will be a lot of dust and dirt. The depth of the groove of the groove should be about 20 mm, and the width should be such that all the wires can easily fit in the groove.

As for the ceiling, there are several options for resolving the issue of placing and securing the wiring. First, if the ceiling is suspended or suspended, then all the wiring is simply fixed to the ceiling. The second - a shallow strobe is made for wiring. Third - the wiring is hidden in the ceiling. The first two options are extremely simple to implement. But for the third one will have to make some explanations. In panel houses, floors with internal voids are used, it is enough to make two holes and stretch the wires inside the floor.

Having finished with the gating, we proceed to the last stage of preparation for the installation of the wiring. The wires must be pulled through the walls to bring them into the room. Therefore, you will have to punch holes with a punch. Usually such holes are made in the corner of rooms. We also make a hole for the wire plant from the switchboard to the lighting panel. Having finished chipping the walls, we begin the installation.

We start with the installation of the lighting panel. If a special niche was created for it, then we place it there, but if not, then we simply hang it on the wall. We install an RCD inside the shield. Their number depends on the number of lighting groups. The assembled and ready-to-connect shield looks like this: there are zero terminals in the upper part, grounding terminals at the bottom, automatic machines are installed between the terminals.

Now we put the wire VVG-5 * 6 or VVG-2 * 6 inside. From the side of the switchboard, the electrical wiring is carried out by an electrician, so for now we will leave it without connection. Inside the lighting panel, the lead-in wire is connected as follows: the blue wire is connected to zero, the white wire to the upper contact of the RCD, and the yellow wire with a green stripe is connected to ground. We connect the RCDs in series with each other at the top using a jumper from the white wire. Now we turn to open wiring.

We fix ducts or cable channels for electrical wiring along the lines outlined earlier. Often, with open wiring, the cable channels themselves are trying to be placed near the baseboard, or vice versa, almost under the very ceiling. We fix the wiring boxes with self-tapping screws with a pitch of 50 cm. We make the first and last holes in the box at a distance of 5 - 10 cm from the edge. To do this, we drill holes in the wall using a puncher, drive a dowel inside and fix the cable channel with self-tapping screws.

Other distinguishing features of exposed wiring are sockets, switches and distribution boxes. All of them are hung on the wall, instead of being embedded inside. Therefore, the next step is to put them in place.It is enough to attach them to the wall, mark the places for fasteners, drill holes and fix them in place.

Next, we proceed to the wiring. We start by laying the main highway and from the sockets to the lighting panel. As already noted, we use the VVG-3 * 2.5 wire for this. For convenience, we start from the connection point towards the dashboard. At the end of the wire we hang a label indicating what kind of wire it is and where it comes from. Next, we lay the VVG-3 * 1.5 wires from the switches and lighting devices to the junction boxes.

Inside the junction boxes, we connect the wires with PPE or carefully insulate. Inside the lighting panel, the main wire VVG-3 * 2.5 is connected as follows: brown or red core - phase, connected to the bottom of the RCD, blue - zero, connected to the zero bus at the top, yellow with a green stripe - ground to the bus at the bottom. With the help of a tester, we "ring" all the wires in order to exclude possible errors. If everything is in order, call an electrician and connect to the switchboard.

The hidden wiring is quite simple. A significant difference from the open only in the way of hiding the wires from the eyes. Otherwise, the actions are almost the same. First, we install the lighting panel and the RCD machines, after which we start and connect the lead-in cable from the side of the distribution panel. We also leave it unconnected. An electrician will do this. Next, we install distribution boxes and socket boxes inside the niches made.

Now let's move on to the wiring. We are the first to lay the main line from the VVG-3 * 2.5 wire. If it was planned, then we lay the wires to the sockets in the floor. To do this, we put the VVG-3 * 2.5 wire into a pipe for electrical wiring or a special corrugation and lay it to the point where the wire is output to the sockets. There we place the wire inside the groove and put it into the socket. The next step will be to lay the VVG-3 * 1.5 wire from the switches and lighting points to the junction boxes, where they are connected to the main wire. We insulate all connections with PPE or electrical tape.

At the end, we call the entire network with a tester for possible errors and connect it to the lighting panel. The connection method is similar to that described for open wiring. Upon completion, we seal the grooves with plaster putty and invite an electrician to connect to the switchboard.

Laying an electrician in a house or apartment for an experienced craftsman is quite easy. But for those who are poorly versed in electrical engineering, you should use the help of experienced specialists from start to finish. This, of course, will cost money, but this way you can protect yourself from mistakes that can lead to a fire.