How to put the machine after the counter. Connecting a single-phase electric meter and machines: standard diagrams and connection rules

Below is a photograph of the wiring diagram for connecting the meter, circuit breakers and RCDs to each other in the electrical panel. The scheme is typical for a small city apartment or country house.

Electricity from the automatic switch installed in the electrical panel of the entrance is supplied directly to the electricity meter. If there is no RCD, then from the meter the phase wire L goes directly to the circuit breakers, and the zero wire to the terminal strip. The PE earth wire is connected directly to the earth bar.

If it is necessary to install an RCD in separate branches of the electrical wiring, for example, a bathroom, then it can be included in the wire gap anywhere, both before and after the circuit breaker. You can install the RCD directly on the wall before entering the electrical wiring in the bathroom in an additional small electrical box.

My shield was created for the existing electrical wiring and consists of just an electric meter and two circuit breakers. I replaced the connection of wires with a terminal strip and jumpers with soldered twists. There is no PE ground wire in the apartment wiring, so it was left unconnected.

How to choose and connect an electric meter

Electricity meters are mechanical, electromechanical and electronic. Currently, as a rule, they install electronic ones. Regardless of the design differences, the meters are connected according to the same electrical circuit.

The photo shows the electrical connection diagram using the Mercury 200 electric meter as an example. The phase wire coming from the entrance shield is always connected to the first left contact of the meter, and the load is connected to the second, from which the phase wire comes out. The neutral wire is connected to the following contacts, which are interconnected inside the meter. After connecting the wires to the electric meter, the screw group is closed with a lid and sealed.

How to choose an electric meter

When replacing mechanical electricity meters and when installing new electrical wiring in an apartment, as a rule, electronic two-tariff electricity meters are installed. The ability of the meter to separately take into account the electricity consumed during the day and at night will reduce the cost of paying for electricity, since the night tariff is cheaper.

When choosing an electric meter, you need to take into account only three parameters: - the number of phases, the maximum load current and the accuracy class. The current consumed even in the apartment most saturated with electrical appliances does not exceed 60A. The optimal accuracy class is the second, because the higher the accuracy of the readings, the more expensive it is.

Thus, for installation in any apartment, an electronic single-phase two-tariff electric meter of any type for a load current of 60 A of the second accuracy class is suitable. The budget model is the counter of the domestic manufacturer "Mercury 200.02", which is installed in my apartment and has been working reliably for more than 10 years. Its appearance is shown in the photographs of this article.

If there is a desire to independently study all the intricacies of choosing and installing an electric meter, then I recommend reading an article specially devoted to this issue, the link to which is given below.

Types of electric meters by design, a comparative table for selection. Table of power consumed by household electrical appliances. Wiring diagram for connecting a single-phase meter in an electrical panel. How to fix the meter on a DIN rail and connect the wires correctly.

How to choose and connect the machine
wiring protection

A separate article is devoted to this issue on the site, which can be found by clicking on the link below.

How to choose an automatic machine according to the wire cross section and type B, C and D, marking, electrical connection diagram, device and principle of operation. How to fix and remove the machine in a shield on a DIN rail, the rule for connecting wires. Why is it forbidden to install a circuit breaker on the neutral wire.

Residual current device (RCD)

The name of the RCD, which was created by Schutzapparategesellschaft Paris & Co in 1937, from my point of view, does not accurately reflect the purpose of the device. It would be more correct to call UZCH - a device for protecting a person from electric shock, for which it is intended. I doubted the need to install an RCD and did an analysis before making a decision.

The principle of operation of the RCD

Outwardly, the RCD looks like a two-pole modular short-circuit circuit breaker, inside which a release mechanism and a differential transformer are installed. In appearance, the RCD differs from the machine only in the presence of an additional "Test" button, which serves to check the RCD's health. If you press it, then the RCD will work.

What is a residual current device (RCD) and its purpose. Table of main technical characteristics and recommendations for selection. Advantages and disadvantages of electromechanical and electronic RCDs. Electrical diagram of electromechanical and electronic RCDs, installation in an electrical panel.

The need to install an RCD

When installing an RCD, four additional mechanical connections appear in the wiring, which, as practice shows, disrupt its operation most often.

In old electrical wiring, due to leakage currents, there is a high probability of false positives of the RCD. False alarms can also be caused by some electrical appliances due to the peculiarities of their device. In modern electrical wiring, through a contact in an electrical plug, the metal part of the case of any electrical appliance is automatically grounded, and if a phase hits the case due to insulation breakdown, the circuit breaker will trip. In addition, it is worth noting that all portable household electrical appliances are double insulated.

Thus, the existing protection measures without RCD, while observing the elementary safety requirements, reliably protect a person from electric shock.

The analysis showed that the installation of an RCD is more a tribute to fashion than a vital necessity, leading to a decrease in the reliability of electrical wiring in general and unjustified costs.

For those who decide to install an RCD, it is possible to replace the circuit breaker and RCD with one device that performs two functions at once - short circuit protection and RCD.

To select a differential machine, the parameters of the short-circuit protection circuit breaker and RCD are first determined according to the above method. Based on the obtained parameters, the type of differential automaton is selected.

How to properly connect wires to an electric meter

When I clamped the wires in the terminals of the electric meter, before clamping, I simply removed the insulation from the wires by one and a half centimeters and inserted them into the terminal.

While typing this article, I realized that the connection could be made more reliable. The terminals at the Mercury 200 counter are two flat plates, between which wires are clamped. The width of the plates is about 5 mm. Therefore, the opportunity to increase the contact area of ​​the wires with the terminals in a simple way was missed. And now it's too late to redo it, since the counter is sealed.

The wiring in my apartment is made with a wire with a diameter of 1.8 mm, therefore, if the wire is bent, as in the photo, it will freely enter the meter terminal and thus the contact area of ​​\u200b\u200bthe wire with the terminal will double. In addition, the skew of the contact plates in the terminals will be eliminated. In this way, it is desirable to connect wires to RCDs or circuit breakers, if their connecting terminals are flat and the wire diameter allows.

DIN rail for mounting
circuit breakers and RCDs

The most common way to mount electrical switching devices, whether it be circuit breakers, RCDs, relays, transformers, sockets and many others, is to mount on the so-called DIN rail using latches.

The name "DIN rail" came to us from Germany, the abbreviation DIN stands for Deutsches Institut fur Normung. The DIN rail is the standard for all European countries. In Russia, a DIN rail in accordance with GOST R IEC 60715-2003 is designated TN35. The DIN rail is a cast or stamped profile made of steel or aluminum with a width of 35 mm. The length of the rail is selected based on the number and width of electrical switching devices planned for installation.

The DIN rail has gained wide popularity among electricians due to its ease of connection, ease of installation and removal from the electrical panel. It only takes a few seconds to install a circuit breaker on a DIN rail. It is necessary to start the switch with a groove for the upper ledge of the rail and press the lower edge of the switch. The spring-loaded latch on the switch securely fixes it. The latch is highlighted in pink in the photo.

To dismantle the product from the DIN rail, it is enough to insert the blade of a screwdriver into a special eyelet at the bottom of the product and take it aside. The latch will come off and the appliance can be removed.

There are electrical appliances that can be dismantled without tools. Here is a photo of the dismantling scheme of an electrical appliance with a mount of this design.

To prevent unauthorized movement of electrical appliances, limiters are additionally installed on the DIN rail. The DIN rail on the shield is attached directly to its rear wall with screws.

How to make and fix
do-it-yourself electric shield

Attention! Before working on replacing or repairing the meter and circuit breakers, in order to avoid electric shock, it is necessary to de-energize the electrical wiring. To do this, turn off the circuit breaker in the switchboard, which is usually located on the landing and check the reliability of its disconnection using the phase indicator.

When I entered the apartment, I moved the shield with the meter and plugs to another wall, as it stood on the passage of the corridor, and it was possible to break it by hooking it. At that time, circuit breakers were not installed in the apartment wiring, and electric plugs were the best protection against short circuits.

Therefore, the installed plugs with fusible inserts, taking into account the electrical circuit and the cross section of the wiring wire, were replaced by automatic plugs with a protection current of 16 A. They worked reliably for twelve years, successfully protecting the wiring from short circuits, while simultaneously performing the function of a switch. By pressing the small red button on the cork-machine body, it was possible to turn off the power supply, and to turn it on, it was necessary to press the white button. The electricity meter was mechanical, and despite the fact that it had worked for more than 50 years, it was in working condition. Therefore, the counter was not replaced.

For aesthetic reasons, it was decided to install the electrical panel in a niche. To improve electrical safety, the standard metal shield was replaced with a self-made one made from a 5 mm thick fiberglass sheet.

On the wall in a niche, the electrical panel is fixed at the corners on four posts installed in the wall with a mortar with M4 screws. In order for the threads of the posts to coincide with the mounting holes of the shield and be at the same level, you must first attach the shield to the place of its planned installation, mark the points of the mounting holes on the wall. Then, in these places, drill holes with a diameter of 4-5 mm larger than the outer size of the racks, 4-5 cm deep.

Next, you need to fix the racks on the shield, fill the holes in the wall with a solution, for example, a rotband, and install the shield, squeezing out the excess solution with the racks. Leave everything in this position for a day. Alabaster or gypsum can be used as a solution. But these solutions set quickly and therefore it is more difficult to work, but you won’t have to wait a day.

Repair of contacts for connecting wires to the meter

A few years after the overhaul of the electrical wiring in our house, suddenly the light bulbs in the apartment began to wink periodically. At first I thought that this was the result of the operation of an electric welding machine, since repairs were carried out in the house. But at night, the flashing of the lamps also sometimes appeared. It became obvious that the matter was in the electrical wiring of the apartment. The wires in all the electrical junction boxes I had were twisted and soldered with solder, so I immediately ruled out this cause. It remains to check only the connection of the wires in the electrical panel.

An external examination of the electrical panel and the meter with automatic plugs did not reveal any violations. The protective covers were removed from the plug holders. The points of contact with plugs and wire connections were in perfect condition, although they had stood without maintenance for more than 12 years. Obviously, washers with growers and rings at the ends of the wires provided reliable contact.

The electric wires suitable for the electric meter were covered by its body. The counter was installed in my absence by a professional electrician and cheated. I was too lazy to drill a mounting hole in the right place and screwed the self-tapping screw into the nearest hole left from fastening the removed mechanical electric meter. As a result, the new electric meter was very close to the bottom wall of the niche and covered the electric wire from inspection. In addition, the current-carrying cable coming from the shield in the entrance was not threaded through the holes in the meter's electrical panel, but was put next to it.

It was impossible to remove the cover covering the terminals for connecting wires, since it was sealed, in the photo there is a seal in the form of a yellow cylinder. To inspect the wires, there was only one possibility, to remove the electric meter from the shield completely.

The electricity meter "Mercury 200" on the shield panel was fixed with a transitional metal bar. However, the mounting system of the Mercury 200 electric meter allows it to be installed in an electrical panel and on a standard DIN rail 35 mm wide. The adapter plate on the electrical panel was screwed with three screws, and the electric meter was already fixed to it with the help of latches. In the photo, the fastening elements are highlighted in a light tone. The arrows show which place on the bar the clamps cling to.

When the sealed cover is removed, it is enough to insert a screwdriver blade into the holes marked with arrows and press the latches. It was impossible to remove the cover on your own, I had to remove the entire electric meter from the mounting panel. The electric meter was installed in a niche, and in order to gain access to the latches, the shield had to be removed first.

My assumption was confirmed, after removing the electric meter, a burnt phase wire of the electrical wiring was found in the output terminal of the meter. The wire was badly clamped and when it moved under voltage, sparks jumped between it and the terminal. It was necessary to strip the wire and terminal contacts.

To resolve the issue with the seal, he called the emergency service, which arrived in a couple of hours, and the electrician officially removed the seal and issued an Act. After that, I released the electricians, to their joy, and started not only repairing, but also modernizing the electrical panel. For a long time I was going to replace automatic traffic jams with modern automatic machines, which were purchased in advance and were waiting for installation.

The wire heated up so much that even the plastic case of the meter melted a little at the point where the wire exited it. But fortunately, this did not harm the electricity meter itself.

The clamping screws of the terminal were unscrewed and, using a semicircular needle file, the upper and lower contacts of the terminal were ground to a brass shine. Now the counter is repaired and ready for further operation.

Installation of electrical appliances on a homemade shield

The choice of a meter, circuit breakers and RCDs for electrical wiring has been made. The rules for connecting them have been studied, therefore, you can proceed with the installation of the selected electrical appliances on the shield.

It is customary to connect neutral N and grounding PL wires into separate groups using the terminal strip shown in the photo. But I have repeatedly met a burnt neutral wire with this method of connection.

Therefore, I decided to connect the wires by twisting followed by soldering. The phase wire going from the meter to two circuit breakers was branched by twisting two pieces of wire, followed by soldering the twist. The neutral wire going directly from the meter to the wiring was also branched in the same way. The connections were insulated with three layers of electrical tape and placed behind the shield.

In place of the holders of automaton caps, a DIN rail was installed with a margin of two standard sizes in length so that, if necessary, it was possible to install additional devices. Two circuit breakers are mounted on a DIN rail. Thanks to the installation of the electric meter a little higher, the wires connected to it became available for visual inspection and it became possible to touch the wires in order to check the reliability of contact with the meter terminals by heating them. Since all the wires were hidden under the shield and only their ends for connection were brought out to the front side, the niche with the counter and automatic machines began to look neat.

The electrical panel is still not a decoration of the hallway. Therefore, the niche was closed with a picture hung on a carnation. All inspectors like this solution very much.

Boxing for electric machines is used for domestic and industrial purposes, because it houses an electric meter, circuit breakers and other devices. The switchboard protects people from electric shock and allows you to protect installed devices from various damages both indoors and outdoors.

General information and design of the electrical panel

Any box for electric machines has its own necessary protection, which prevents physical impacts with current-carrying elements and prevents foreign objects from getting on them that can cause a short circuit. And also the electrical panel has a fairly simple design, outwardly, it resembles a box in which they are installed:

The design is made of metal or plastic. Each product has its own characteristics, so the plastic shield has increased resistance to external influences and does not conduct electricity. The metal cabinet has many modifications, which allows you to choose the desired design.

Depending on what type of wiring is installed, shields for electric meters and machines are divided into two types:

1. Outer. Used for open wiring.
2. Inner box for electric meter. Required for concealed wiring.

The size of the shield depends on the number of modules that will be installed there. In addition to the standard switch cabinet includes:

After purchasing and checking all the components, you can install an electrical panel. During installation, it should be remembered that if the network is single-phase, a two-pole automatic machine is installed, and for a three-phase one - a three-pole one.

The electric box for outdoor installation is mounted under the base of non-combustible material. The lower edge of the box cabinet must be at least 100 cm above the floor level, and the upper part must not exceed 180 cm. Lowering the level is allowed if disabled or elderly people live in the living room.

Places prohibited for the installation of an electrical panel:

• near heating systems;
• in showers;
• outside the residential premises, with the exception of metering boards;
• in the bathroom;
• in the ventilation shaft;
• flight of stairs;
• loggias and balconies.

As a rule, a street box for an electric meter is installed next to the entrance to the room. The apartment is mounted construction near the front door. In panel houses, tambour rooms are provided for the installation of the product.

Assembly rules

A certain amount of electrical cable must be connected to the junction box. To save time, it is better to sign them. Each wire must be freed from insulation and the phase conductor must be marked. Then, using self-tapping screws, fix the DIN rail and install the circuit breaker on top. When all products are inside the shield, you need to do the following step by step:

You need to know that before you connect the device, you need to get permission for independent connection from the controllers of the energy company. If permission could not be obtained, then they perform the connection on their own. It should be remembered that after installing the meter, it is necessary to mount a protective shutdown device to it. After all, it protects the electrical box from short circuits and limits the permitted power.

For assembly, it is necessary to use a multi-core cable PuV, but it is also allowed to use its analogue - PuGV, if the twisted wires at the end are covered with special lugs. Cable insulation of these brands is made of non-combustible material, and is able to maintain its properties at temperatures from minus 40 to 75 degrees. The service life of products reaches 20 years.

To conduct a phase to the input of the machine, you need to use the "comb" as a distribution bus.

Tips for assembling an electric meter:

In addition, all wires must be marked, this requirement also applies to installed products. And on the door should be a table indicating the purpose of each element.

Electric meters and circuit breakers are essential attributes of the power grid. These devices are mounted in special switchboards, which are already installed in the entrances of houses. This is not provided for in private houses, however, the modern market allows you to choose any shield for an electric meter and machines of a suitable size and design. The appearance of such a box is now important, as it is being installed more and more often inside the house. In this article, we will get acquainted with the feature of such boxes, what types they are, and what to look for when buying.

What is

The standard equipment of the electrical panel is as follows:

• Electric meter;
• Differential machines;
• Introductory machine;
• Automatic switches;
• 2 tyres.

Now let's get acquainted with the built-in elements, and what they are used for:

• DIN rail. It is a special device made of metal plates. It happens that the rail is too long, in which case it is cut with a hacksaw;
• Electric meter. Necessary to take into account the consumption of electricity;
• Automatic switches. This equipment protects electrical wiring. Before installing them, you need to know what is the power of the devices that will be connected to the network;
• Distribution bus. With its help, neutral wires are connected. There are closed and open;
• RCD. A residual current device that ensures safety against electric shock;
• Electrical wiring.

Where is the shield installed?

Before installing the box in the apartment, first of all, it is necessary to draw up a detailed plan, take into account how the rooms will be furnished, where there will be lamps and switches for them, various household appliances, and so on. Along with electrical wires, other engineering communications, heating pipes, pipelines, alarms, the Internet, and so on are laid. The project should be developed in such a way as to optimize the routes of the described systems.

Important information! An electrical panel is a place where a cable from an energy supply company is connected to a meter in order to further distribute electricity to consumers.

While doing the project, you should determine the most suitable place where the electrical panel will be installed. In the last century, it was mounted directly on the landings, but now the installation method is being popularized right in the apartment. This is not only convenient, but also ensures that unauthorized persons will not have access to the box.

As practice shows, the most suitable place is the corridor, near the front door and at face level, in order to more conveniently track the meter readings. Mounting the box in this way does not require a large length of the supply cable.

Those who live in a country house will need to take into account more subtleties: how to safely organize an input device into a building, how a branch from an overhead power line is designed. In addition, you will need to contact the power supply organization to find out the details regarding their device.

Features of choosing a shield

When choosing a box, you need to understand that they are divided according to the following parameters:

• What material are they made from?
• In what area are they used?
• Mounting method;
• The amount of equipment placed inside.

Note! When choosing a shield, you should pay attention to such a parameter as the IP protection class. For indoors, the class should be 30 or 40, for outdoors - 65 or 67.

The degree of protection IP is how well the devices are isolated from dust and moisture. The higher the number, the higher the protection. Eg:

• IP20 - installed in apartments. 0 - no moisture protection. 2 - provides protection against large dust particles;
• IP21-23 - installed in unheated enclosed spaces or under awnings;
• IP44 - installed outdoors, under visors or with additional protection;
• The most protected shields are those whose protection class is IP54 and IP66 - they are installed outdoors and are not afraid of exposure to rain or wind.

Note! It is convenient if the cabinets installed in the entrances or on the street have a viewing window that allows you to take readings. Working with such shields, you do not have to open the door every time.

A modern shield for an electric meter is made from a variety of materials, such as:

• Plastic. Such boxes are installed inside apartments and office premises. The products themselves may differ in internal configuration, colors and external design. A lock may be provided on the door. When choosing a shield made of plastic, you must be careful with the manufacturer's data. You should not choose products from little-known suppliers at low cost - such boxes are made of low-quality plastic, which yellows over time under sunlight. These products have both pros and cons. The main advantage is ease of installation. The shield is easily mounted into drywall or similar walls. For the manufacture of electrical panels, a dielectric material is used, so they do not require additional grounding. Plastic cases are characterized by durability and visual appeal, so they are in harmony in any interiors. The disadvantage of the material is that it is combustible and quite fragile. If the shield installed in the wall gets damaged, it will be difficult to replace it;
• Metal. Boxes with a metal case are installed in garages and in open spaces. They are strong, durable and resistant to external influences. In addition, they are not flammable and are not afraid of high temperatures. However, the disadvantage is significant: mandatory grounding is required, and the metal itself, being in an aggressive environment, corrodes. As a rule, metal boxes are installed at the entrances of apartment buildings or at enterprises.

If you intend to install it outdoors, then it is better to pay attention to the anti-vandal design, for the manufacture of which sheet steel with a thickness of 1.2 mm or more is used. These boxes are equipped with two doors: one is blind, the second is a viewing window for the meter.

Advantages of installing a shield on the street:

• Quick access to the electric meter by the inspector;
• In some country residences, shields reach impressive sizes, therefore, in order to save free space, they are taken out into the street;
• If the shield does not fit into the interior of the interior, it is mounted on the street.

Cons of street accommodation:

• Based on the rules of the PUE, outdoor cabinets should provide for local heating, which provides the meter with a positive temperature. It is not always possible to comply with this condition, and induction devices at sub-zero temperatures simply “lie”;
• In order to take readings from the meter, it is necessary to go outside, where there may not always be good conditions;
• Necessity of constriction of group lines.

The type of shield mounting also differs, so they are:

• Overhead. They are installed on the surface of the walls. Allow to distribute open and hidden wiring;
• Embedded. Mounted in niches located in the walls. Used only for hidden wiring.

Depending on how much additional equipment will be installed, you should decide on the capacity of the shield. Electric boxes have a different configuration, depending on the number of places: 12, 24, 32, 64 and more. One place has a standard distance - from 17 to 18 mm. You need to be careful, since each device takes up a certain number of places. Experts recommend using boxes with a margin of space (especially for built-in shields), which may be required when upgrading the electrical circuit. The minimum size of such devices is 16-24 seats.

• Technical specifications;
• Manufacturer reliability.

To determine the technical parameters, simple calculations will be required, but making sure that the manufacturer is reliable is not so simple. In the modern market there are inexpensive counterfeit products. In addition, you can stumble upon an outright fake of a well-known brand. Therefore, when choosing equipment, you should check the availability of the appropriate certificate, especially when it comes to metering devices. No power supply company will connect non-certified equipment that has not been tested.

At the moment, many companies are engaged in the production of boxes. Based on practice, preference should be given to the following companies: ABB, IEK, Makel. If electrical work is required, these brands appear most often. Products from ABB are considered the highest quality, and the last 2, although inferior in quality, are popular due to their affordable cost. If the main preference is the visual component and at the same time reliability, you need to choose equipment from the Greek manufacturer FOTKA.

How to install the counter in the shield

Before installing the meter, you need to figure out in what order the device will be connected to the electrical line. In some cases, the controllers approve the independent connection of equipment. It is better to provide a protective shutdown device in front of the meter. As a rule, in the case of a single-phase network, a two-pole circuit breaker is installed. The functions of this device are as follows:

• Provides meter short circuit protection. Allows you to carry out preventive work;
• Capable of limiting the allowed power.

By setting the counter, other actions are performed:

• The meter is attached to the shield with a special latch;
• It is necessary to install outgoing single-pole circuit breakers.

Regulations state that the electricity meter must be installed at a height of 80 to 170 cm.

A person is constantly surrounded by various electrical appliances. Modern devices can conduct current, which happens most often due to damaged insulation. If the device is not grounded, it is very dangerous to touch it. To avoid accidents, an RCD is recommended for installation. The purpose of the device is to protect against electric shock (short circuit or damaged insulation).

Shield installation

It is necessary to decide where the box will be fixed. As a rule, this is a hallway, not far from the input of the power cable. It is installed at a height of 1.5 to 1.7 meters. Holes are made in the wall, and the box itself is fastened with dowels or self-tapping screws.

After the shield is installed on the wall, its assembly is as follows:

• In advance, all groups of wires must be brought to the shield. They must be marked, which will facilitate assembly according to the scheme;
• Using self-tapping screws, a DIN rail is attached to the shield, on which the devices will be installed;
• The upper part is equipped with a bus for neutral, the lower one for grounding;
• In the upper part, an automatic input is installed;
• The introductory machine can be located in a separate box, like the counter;
• As for the groups of machines, they are placed from top to bottom, as the power decreases. The jumper between them is a special bus, or a copper wire with a cross section of 4 mm is used;
• Cables and wires are introduced into the box through the provided hole. It is necessary to cut off the outer braid from them, and the gasket is carried out by color. It is necessary to leave a margin that may be needed for further repairs. Zero cores are connected to the top bus. Power is supplied to the upper terminals, the load is connected to the lower ones;
• When connecting each group, it is recommended to check its performance by applying voltage through the temporary connection circuit.

Important! Initially, the shield is assembled without switching, which allows you to mark the installation locations of the devices. If necessary, the power must be quickly turned off, both from the outside and from the inside, which must be provided for.

In the closed state of the shield, it is important that it is possible to check the voltage with an indicator screwdriver.

When choosing a shield, it is necessary to build on the size of the electric meter and the number of packages installed. In any case, you will have to resort to the help of an electrician: to connect the common circuit and to seal the meter. Picking up a box is not difficult, but first you need to correctly draw up a project so as not to make a mistake.

Video

Few will remember the time when the calculation of electricity bills was based on the number of lighting fixtures in the house, which, of course, did not allow to accurately determine the amount of energy consumed.

Today, such a method, of course, is unacceptable, since there are many modern metering devices with a high accuracy class.

If you plan to connect a new meter on your own, and you need a simple connection diagram, then carefully studying this article will help you avoid difficulties during the installation process.

So, before connecting the electric meter, it is necessary to coordinate the following details with the energy supply organization:

Since not everyone knows how to properly connect an electric meter, many make mistakes during installation, although there is nothing complicated here.

Let's consider in more detail how to connect an electric meter and machines:

• to protect the measuring device from overvoltage in the network, automatic machines are installed before the line is entered into the meter
• if the machines are installed after input, with significant voltage fluctuations, the device will simply fail
• according to the regulatory documentation, only one machine is allowed to be installed on the phase wire, but if possible, it is preferable to install a two-pole one, which will cut off both the supply and the neutral.

The machines are fixed on a DIN rail, while it must be necessarily grounded on the body of the electrical panel, if it is not its constituent element.

A single-phase electric meter is designed as follows - all consumers of electrical energy in the house are powered from one wire (phase). A single-phase device has four terminals through which electricity is supplied to the premises, as well as communication with a common power grid.

Consider step by step how to connect a single-phase electric meter:

1. First of all, it is necessary to de-energize the room, and then remove the old meter.
2. The new device is fixed in a pre-prepared place.
3. A phase wire is connected to terminal No. 1. As a rule, it is red, but if you have any doubts, you can test it with an indicator screwdriver - the indicator on the phase wire should light up.
4. The phase wire from the apartment network is connected to terminal No. 2. Thus, the first circuit is ready.
5. In a similar way, a neutral wire from the apartment and general networks is connected to terminals No. 3, 4.

Before connecting the electric meter, read the diagram of its connection.

In this case, consumers of electrical energy are divided into groups, which is considered safer.

Connecting a three-phase meter is somewhat more difficult, but the principle is still the same. This controller has 8 terminals. Consider a step-by-step instruction on how to connect a three-phase electric meter:

Before connecting the Mercury electric meter, it is advisable to consider its design features. The meter is made in a plastic rectangular case. On the front panel of the electric meter there is an LCD display. On the right side is a plate with the main characteristics. The metering device is characterized by compact overall dimensions and low weight.

The lower removable panel of the meter protects the contacts of the device. The connection of the cable to these contacts is carried out by means of a screw connection.

The Mercury meter is connected in the same way as any electrical energy meter. The main requirement is the choice of output and input conductor. The input input will be as determined by the power supply company. In this case, any wires can be used as output conductors.

Now you know how to connect the electric meter correctly, but do not forget that self-replacing the device without the consent of the company that supplies electrical energy is strictly prohibited. Without permits for the installation of new equipment, the old electric meter is also prohibited from being removed.

To control and record the consumed electrical energy, you need a special device - an electric meter. Both at large manufacturing enterprises and in private apartments, when concluding a contract for the supply of electricity, one cannot do without this device.

When installing a meter to calculate the spent electricity, it is necessary to correctly connect it to the power supply circuit.

Electric meters are either single-phase or three-phase, direct or indirect connection.

In this article, we will describe in detail how to independently connect both types of electricity meters.

A single-phase electric meter is connected directly to the break in the power line. Before installing the meter, no electrical consumers should be connected to the power line. To protect the power supply line, it is advisable to install an introductory circuit breaker in front of the meter. It will be necessary when replacing the meter so as not to de-energize the entire supply line.

After the meter, it is also necessary to install a circuit breaker, it will protect the outgoing line and the meter itself if a malfunction occurs in the electrical consumer circuit.

When connecting an electric meter, you need to pay attention to the connection diagram, it is usually located on the back of the terminal cover. A single-phase meter has four terminals for connecting wires:

1. Phase wire input.
2. Zero wire input.
3. Phase wire output.
4. Zero wire output.

Connection of a single-phase electric meter

The power wires after the introductory circuit breaker are stripped of insulation by 15 mm and connected to terminals 1 and 3, the outlet wires are also stripped of insulation and connected to terminals 2 and 4, respectively, on the diagram on the cover of the device.

Mercury meter connection diagram

Such an electric meter connection scheme is suitable for an apartment in a multi-storey building, a garage, a country house, or for a small shopping pavilion.

Connecting a modern electronic meter such as Micron is no different from the above scheme, which can be used to install any single-phase metering device.

Video: connecting a single-phase single-tariff electric energy meter

There are two types of connection of a three-phase meter, direct and indirect, through isolating current transformers.

If it is necessary to take into account the consumption of a relatively small number of three-phase low-power consumers, then the electricity meter is installed directly into the break in the supply wires.

If it is necessary to control sufficiently powerful consumers of a three-phase electrical network, and their currents exceed the nominal value of the electric meter, then it is necessary to install additional current transformers.

For a private country house, or a small production, it will be enough to install only one meter, designed for a maximum current of up to 50 amperes. Its connection is similar to that described above for a single-phase meter, but the difference is that when connecting a three-phase meter, a three-phase supply network is used. Accordingly, the number of wires and terminals on the meter will be greater.

Connecting a three-phase meter

After the counter, for protection, automatic switches are installed. For three-phase consumers, three-pole machines are installed.

More familiar, single-phase electrical appliances can also be connected to such a meter. To do this, you need to connect a single-pole machine from any outgoing phase of the meter, and take the second wire from the neutral ground bus.

If you plan to install several groups of single-phase consumers, they must be evenly distributed by powering circuit breakers from different phases after the meter.

Wiring diagram of a three-phase electric meter

If the consumed load of all electrical appliances exceeds the rated value of the current that can pass through the meter, it is necessary to additionally install isolating current transformers.

Such transformers are installed in the gap of power current-carrying wires.

The current transformer has two windings, the primary winding is made in the form of a powerful bus, threaded through the middle of the transformer, it is connected to the break in the power wires of the power supply to electrical consumers. The secondary winding has a large number of turns of thin wire, this winding is connected to an electric meter.

This connection is significantly different from the previous one, it is much more complicated and requires special skills. We recommend to invite a qualified specialist to connect a three-phase meter with current transformers. But if you are confident in your abilities and have a similar experience, then this is a solvable task.

It is necessary to connect three current transformers, each for its own phase. Current transformers are mounted on the rear wall of the introductory study cabinet. Their primary windings are connected after the introductory switch and a group of protective fuses, into the gap of the phase power wires. A three-phase electric meter is installed in the same cabinet.

Connection is made according to the approved scheme.

Connection diagram of current transformers

To the power wire of phase A, before the installed current transformer, a wire with a cross section of 1.5 mm² is connected, its second end is connected to the 2nd terminal of the meter. Similarly, connect wires with a cross section of 1.5 mm² to the remaining phases B and C, on the meter they fit to terminals 5 and 8, respectively.

From the terminals of the secondary winding of the current transformer, phase A, wires with a cross section of 1.5 mm² go to the meter to terminals 1 and 3. The phasing of the winding connection must be observed, otherwise the meter readings will not be correct. The secondary windings of transformers B and C are connected in a similar way, they are connected to the meter to terminals 4, 6 and 7, 9, respectively.

The 10th terminal of the electric meter is connected to a common neutral grounding bus.

On each landing of a multi-storey residential building, there is a metering board with electric meters that calculate the consumption of electricity on the entire floor. What you need to install the meter in the switchboard:

1. Prepare the necessary tools: wire cutters, pliers, stripping pliers, screwdrivers, electrical tape, etc.
2. Access to the introductory switch to disconnect the line of this floor from the network.

Wiring diagram for the meter and circuit breakers.

Connecting the counter at the entrance

First you need to make branches from the supply line. To do this, pre-de-energized main wires are stripped of insulation using special pliers, at a distance of 3 cm. A special terminal block is placed in this place for branching the wire. After installing the terminal block on the main wire, a lead wire is connected to it, which will go to the introductory machine.

Similarly, a branch is made from the zero main wire.

Then they install all the protection devices, and the meter itself, on the shield panel, it is more convenient to do this using a Din-rail. After installing all the components in place, the wires are connected.

The branch made from the phase main wire is connected to the input machine, then from the output of the input machine the wire is connected, according to the diagram, to the first terminal of the meter. The branched neutral wire is connected immediately to the second terminal of the meter; a circuit breaker is not needed for it.

From the third terminal, the wire goes to the group consumer protection circuit breakers. The wire from the fourth terminal is connected to a common grounding bus, all neutral wires from consumers will also be connected to it.

The phase wires coming from the apartment are connected to the lower terminals of the circuit breakers, which are installed after the meter. For each phase wire (group of electrical appliances) it is necessary to install a separate circuit breaker. It is forbidden to connect several phase wires to one machine.

All neutral wires from the apartment's electricity consumer groups are connected to a common grounding bus.

Remember that in the shield in the stairwell, not only your meters and circuit breakers are located, but also your neighbors. To avoid confusion in the event of any malfunctions, be sure to make marks with the apartment number on your circuit breakers and meter.

Installing an electricity meter for a garage is similar. The only difference is that there is no need for a branch of the main wires, since ready-made separate power wires are brought into the garage.

It is difficult to imagine a switchboard without modern modular protection devices, such as circuit breakers, residual current devices, differential circuit breakers and all kinds of protection relays. But not always these modular devices are connected correctly and reliably.

In view of the maintenance of electrical panels, I sometimes have to deal with connection errors of the circuit breakers that are installed in them. It would seem, how can you incorrectly connect a conventional single-pole machine? I stripped the cable to a certain length, inserted it into the terminals, tightened the screws securely.

But no matter how strange it may sound, most people have "clumsy" hands and the build quality of the shields leaves much to be desired. Although, in fact, we all make or have made mistakes in one industry or another, and as the well-known proverb says: "he who does nothing makes no mistakes."

Greetings to all friends on the website "Electrician in the House". In this article, we will consider and analyze several options for the most common and gross errors.

The first thing I would like to start with is the correct connection of the machine in principle. As you know, the circuit breaker has two contacts for connecting a movable and a fixed one. On which of the pins you need to connect power to the top or bottom? To date, there has been a lot of controversy about this. There are a lot of questions and opinions on this subject on any electrical forum.

Let's turn to the regulations for advice. What does the PUE say about this? In the 7th edition of the PUE, clause 3.1.6. says:

As you can see, the rules say that power wire when connecting machines in the shield should be connected, as a rule, to fixed contacts. This also applies to all ouzo, difavtomat and other protection devices. From all this clipping, the expression "as a rule" is not clear. That is, it seems, as it should, but in some cases there may be an exception.

To understand where the moving and fixed contact is located, you need to imagine the internal structure of the circuit breaker. Let's use the example of a single-pole machine to consider where the fixed contact is located.

Before us is an automatic machine of the BA47-29 series from iek. It is clear from the photo that the upper terminal is the fixed contact, and the lower terminal is the movable contact. If we consider the electrical designations on the switch itself, then here it is also clear that the fixed contact is on top.

Circuit breakers from other manufacturers have similar designations on the case. Take, for example, a machine from Schneider Electric Easy9, it also has a fixed contact on top. For Schneider Electric RCDs, everything is similarly fixed contacts on top and movable contacts on the bottom.

Another example is Hager safety devices. On the case of circuit breakers and RCD hager, you can also see the designations, from which it is clear that the fixed contacts are on top.

Let's see if it matters from the technical side, how to connect the machine from above or below.

The circuit breaker protects the line from overloads and short circuits. When overcurrents appear, the thermal and electromagnetic releases located inside the housing react. From which side the power will be connected from above or below for the tripping of the releases, there is absolutely no difference. That is, we can say with confidence that the operation of the machine is not affected by which contact the power will be supplied to.

In truth, I must say that manufacturers of modern "brand" modular devices, such as ABB, Hager and others, allow power to be connected to the lower terminals. For this, the machines have special clamps designed for comb tires.

Why, then, in the PUE, it is advised to connect to fixed contacts (upper)? This rule is approved for general purposes. Any educated electrician knows that when performing work, it is necessary to remove voltage from the equipment on which he will work. "Climbing" into the shield, a person intuitively assumes the presence of a phase on top of the machines. By turning off the AB in the shield, he knows that there is no voltage at the lower terminals and everything that comes from them.

Now let's imagine that connection of machines in the switchboard The electrician Uncle Vasya performed for you, who connected the phase to the lower AB contacts. Some time has passed (a week, a month, a year) and you need to replace one of the machines (or add a new one). The electrician Uncle Petya comes, turns off the necessary machines and confidently climbs with his bare hands under voltage.

In the recent Soviet past, all machine guns had a fixed contact at the top (for example, AP-50). Now, according to the design of modular ABs, you cannot tell where is the movable and where is the fixed contact. In the ABs that we considered above, the fixed contact was located on top. And where are the guarantees that the Chinese automatic machines will have a fixed contact located on top.

For those who do not agree with me, the question of backfilling is why, on electrical circuits, the power to the machines is connected precisely to the fixed contacts.

If we take, for example, a conventional RB type switch, which is installed at every industrial facility, then it will never be connected upside down. The connection of power to switching devices of this kind assumes only the upper contacts. Turned off the breaker and you know that the lower contacts are without voltage.

How do most users connect machines in the shield? What mistakes can be made? Let's look at the errors that are most common here.

Everyone knows that before how to connect the machine in the shield you need to remove the insulation from the connected wires. It would seem that there is nothing complicated here, I stripped the core to the desired length, then insert it into the clamping terminal of the machine and tighten it with a screw, thereby ensuring reliable contact.

But there are cases when people are at a loss as to why the machine burns out when everything is connected correctly. Or why the power in the apartment periodically disappears when the wiring and filling in the shield are completely new.

One of the reasons for the above described is the penetration of the wire insulation under the contact clamp of the circuit breaker. Such a danger in the form of poor contact carries the threat of melting the insulation, not only the wire, but also the machine itself, which can lead to a fire.

To exclude this, you need to monitor and check how the wire is tightened in the socket. The correct connection of the machines in the switchboard should exclude such errors.

If the need arose connect multiple machines standing in the same row from one source (wire) for this purpose, the comb bus is the best fit. But such tires are not always at hand. How to combine several group automata in this case? Any electrician, answering this question, will say to make homemade jumpers from cable cores.

To make such a jumper, use pieces of wire of the same cross section, or better not break it at all along its entire length. How to do it? Without removing the insulation from the wire, form a jumper of the desired shape and size (according to the number of branches). Then we strip the insulation from the wire at the bend to the desired length, and we get an inextricable jumper from a single piece of wire.

A circuit breaker (may also be called a machine, a switch) is a switching device designed to supply electric power. current to the object and its shutdown in automatic mode in the event of a malfunction in the electrical network. ProductsDesign and principle of operation

In order to properly connect the machine to work, it is necessary to understand its design and the principle of operation.

Sectional view of a circuit breaker with a thermal release

The main parts of the product are as follows:

• frame;
• switching device;
• control mechanism (handle, button);
• arc quenching chamber;
• screw terminals (top, bottom).

The housing and control mechanism are made of durable plastic, which does not support combustion. Switching device - these are contacts, both movable and fixed. The pole of the machine is a pair of these contacts, which has its own arc chute. Its main purpose is to extinguish email. an arc that appears at the moment of breaking contacts under load. It is a set of steel plates with a special profile shape. They are equidistant from each other and isolated from each other. The electric arc that has arisen in the process of malfunctions is attracted to these plates. Here it cools down and goes out. The number of pairs of contacts can be from 1 to 4.

For example, a two-pole circuit breaker has 2 moving and 2 fixed contacts. The machine has a position indicator: red means that the product is on, and green means it is off. This allows you to quickly navigate and find out what state the machine is in.

From the outside, only the handle, screw clamps located above and below, and an indicator are visible on the machine. Everything else is inside the device case.

The case has special jaws called a retainer, which allows you to quickly install the circuit breaker on a special rail called DIN. In case of replacement of the product, the same latch allows you to quickly dismantle it: by loosening the fixing screws on the terminals of the machine, it is enough to move the latch down. The machine will effortlessly be removed from the rack. Today, such rails are an integral part of any electrical panel. Many modern electronics and automation elements are made specifically for installation on a DIN rail.

The mechanism that turns off the circuit breaker in case of emergency is called a release. Each type of release has its own device.

The thermal release in its design has a special plate called bimetallic. It is made by pressing from 2 dissimilar metals, which have different coefficients of linear expansion. The plate is connected to the electrical circuit in series with the load. During the operation of the device, the plate is heated by the current passing through it, and it bends towards the metal, which has a lower expansion coefficient. With an increase in current above the nominal (overload), its bending will turn off the machine. For this, a trigger mechanism is provided in the design.

The operation of the circuit breaker is also influenced by the ambient temperature. Therefore, in some products, the response time is adjusted according to this temperature. In any case, the higher the current value from the rated value, the faster the thermal release trips. Some of them work in a matter of fractions of a second.

Sectional view of a circuit breaker with a magnetic release

A coil with a winding and a core is the magnetic release. The winding is made of insulated copper wire. Included in email the circuit is in series with the contacts - the load current flows through it. If it exceeds the set allowable value, then the magnetic field of the coil will move the core, and it, in turn, acts on the disconnecting device. This will cause the circuit breaker contacts to open.

The device of the machine with a combined type of control

Some types of switches provide time delay in case of short circuit and they are called selective. Such a product has a special panel where the switch off time is set. This makes it possible to turn off a specific section where a short circuit occurred and where other automata worked. As a result, there is no need to completely disconnect the object from the power supply, it is possible to disconnect only the area where the emergency situation has developed. As a rule, these are powerful devices with a semiconductor type release.

The design of the machine may not have a release, and then it is called a switch-disconnector.

Before proceeding with the installation, it is necessary to choose the right product. How much to deliver: one or several, for what power, what manufacturer? Do you need an introductory machine? Connect before the counter or after? These are the most frequently asked questions.

Each switch is characterized by the following parameters:

• rated current (indicated in A);
• working voltage el. networks (indicated in B);
• the number of poles;
• maximum short-circuit current;
• time-current characteristic (the response time of the device depending on the magnitude of the flowing current - the limiting switching capacity (PKS)).

Manufacturers usually indicate all this directly on the body of the device, including a circuit diagram for switching on and a switch symbol.

Placement of the technical characteristics of the machine on the body of the device

The choice of the switch is carried out according to the load power and the cross section of the connected wire. They usually choose according to 2 parameters: overload current, short-circuit tripping current.

Overload occurs when devices and devices are connected to the network, the total power of which will lead to excessive heating of conductors and contact connections. Therefore, the machine that will be installed in a particular circuit must have a tripping current greater than or equal to the calculated one. It is determined by summing up the power of electrical devices intended for use (indicated in the passport). Next, the resulting figure is divided by 220 (recall physics and Ohm's law) and the desired overload current is obtained. It is also necessary to take into account one circumstance: this current should not be greater than the current that can flow through the conductor.

Short-circuit breaking current - this is its value at which the circuit breaker turns off. It is also calculated, and then selected according to the type of protection. It contains the values ​​​​of the tripping current in relation to the probable short-circuit current. This current depends on the type of load on the mains. In everyday life and for small objects, devices with the symbol B, C are used, and at the input - D (see the placement of the designation in the figure).

Most often, in addition to automata for each group line, the electrical circuit also includes an introductory automaton, an RCD or a differential automaton.

Connection diagram of protection devices in the switchboard

The diagram indicates the following main points that are important to know:

• a complete set of a switchboard (introductory machine, electric meter, RCD, machines from walking lines);
• paired operation of the introductory machine and RCD (this is evidenced by the lower rated current of the RCD than that of the introductory machine);
• installation location of the RCD (should be close to the power supply, therefore it is mounted immediately behind the meter);
• installation of one RCD that protects the entire electrical circuit (leakage current should not exceed 30 mA);
• when installing the RCD, the zero protective (PE - black lines) and the zero working conductor (N - blue lines) are separated;
• cross-section of conductors and brand of wire;
• how the phase conductor is connected to the main devices of the circuit (in the diagram, the lines are red).

The appearance of the switchboard with installed devices for metering electricity consumption. energy and protection e. circuits shown in the figure below:

Placement of protection elements and a meter in a switchboard

Circuit breakers are manufactured in many countries. The main requirement for this device is that it must be made of quality materials and have a long service life. The price of a machine of the same power can vary quite widely and depends on the manufacturer.

The following companies produce the highest quality machines:

• French: Legrand, Schneider Electric, Hager;
• Slovak SEZ Krompachy;
• German: ABB, Moeller, Kopp;
• American General Electric;
• Russian: Contactor, KEAZ.

Before mounting the switch, it is necessary to clearly determine where to connect the wires or power cable correctly: from above or below the product, or, more simply, to moving or fixed contacts. And although many do not comply with this condition and connect without taking this factor into account, it is still more correct to refer to the PUE, which for electricians is the document whose instructions must be followed. It clearly says: the connection of the supply wire (cable) must be carried out to the fixed contacts. They are in all modern machines are on top.

Installation cannot be carried out without tools and control devices. Must have:

• Screwdriver Set;
• mounting knife;
• tester or screwdriver with indicator.

Installation is carried out in single-phase networks, in which the input is made with 2 wires (usually these are old buildings): phase (L) and zero (PEN), i.e. made according to the TN-C system. The power wire is connected to terminal 1 of the machine, from terminal 2 through the meter it is distributed to machines of specific groups. Zero feeding through the counter is supplied to the PEN zero bus. This is clearly shown in the figure below.

Wiring diagram for single-pole circuit breakers in the switchboard

Installation is carried out in single-phase networks, in which the input is carried out by 3 wires, one of which is phase (L), the second is zero (N), the third is earth (PE), i.e. connection is carried out via TN-C-S or TN-S systems. Here the supply wire is connected to terminal 1, zero to terminal 3 and securely fastened. Terminal 2 is the output, the phase passes through the electricity meter. The input device, which is the RCD, distributes power evenly across the switches, combined into separate groups. From terminal 4, which is the output, zero passes through the electric meter, RCD and is connected to the N bus. The wiring is shown schematically in Figure 10.

Connection diagram in the shield of two-pole circuit breakers

The passport for the machine indicates the requirements for connecting conductors to its terminals. The information must be carefully reviewed. This applies to both the cross section and the type of connection of the conductors, as well as the length of the stripped part.

Usually, for machines used in everyday life, the wires are stripped of insulation up to 1 cm long using a mounting knife. It is also necessary to pay attention to the color coding of the wires. White or brown for the supply wire (phase), blue (blue, black) for the neutral conductor, yellow-green or green for the ground wire.

After stripping with a mounting knife, the bare part of the wire is inserted into the terminal clamp from above or below, depending on which conductor is connected (phase, ground or zero). Then they are securely fixed into the corresponding terminals with screws. Here you will need a screwdriver. The reliability of the fastening of the conductor is checked by twitching. In the case of connecting a flexible wire to the circuit breaker, it is necessary to use special lugs, which makes the connection more reliable.

When connecting conductors to the machine, it is necessary to follow the following factors:

• insulation must not get under the contact clamp;
• do not overtighten, as this may deform the case and, as a result, lead to device failure, malfunction or shortened service life.

In many cases, several circuit breakers are installed in the switchboard. Inexperienced electricians connect them together with jumpers. This is acceptable, but it is better to use a special tire. It's called a comb. It is usually cut to the required size, and then the phases are connected to the machines in the sequence provided for by the principal email. scheme.

Connection bar appearance

To properly electrify an object of any complexity, you must perform the following steps:

• draw up an electrical circuit taking into account all the features of the electrical wiring of a particular object;
• correctly determine the total power consumption;
• determine the number of electrical groups and the power of each group;
• determine the installation location of the switchboard and how many modules it should be;
• choose a metering device (electric meter);
• correctly connect the outgoing and incoming lines;
• to connect the shield to the networks of the energy supply company.

You can learn about the electrical circuit for connecting circuit breakers from the video below.

All this can only be done by competent electricians who are well versed in the power supply of simple and complex objects. They know the modern electrical base and are able to complete the electrical panel with everything necessary at minimal cost. In addition, based on many years of experience, they can provide useful advice on saving energy and improving the supply of electricity to existing facilities.

Circuit breakers, also known as packers or automata, are switching devices whose task is to supply current to the elements of the electrical network, and in case of disruption of its operation, to automatically de-energize. They are mounted, as a rule, in the switchboard, and allow you to protect the circuit from damage caused by excessive loads, voltage drops, and short circuits. In this material, we will talk about how this equipment is classified, what are the features of its operation and how to properly connect the machines in the electrical panel.

Today, these devices are sold in a huge assortment. They differ from each other in the following characteristics:

• main circuit current. It can be variable, constant or a combination.
• Control method. The equipment can be operated manually or by means of a motor drive.
• Mounting method. Devices are plug-in, retractable or stationary.
• Releaser type. These elements can be electronic, electromagnetic and thermal, as well as semiconductor.

• Body part type. It can be modular, cast or open.
• Operating current indicator. Its value can be from 1.6 A to 6.3 kA.

Modern machines are distinguished by a complex network protection mechanism. They have additional features, which include:

• Possibility of opening the electrical circuit at a distance.
• The presence of signal contact groups.
• Automatic operation of the protective device in the event of a voltage drop to a critical value.

Step-by-step diagram for selecting a circuit breaker on the video:

Bags can have different sizes, and with their help you can protect electrical networks not only in apartments and private houses, but also in large facilities. These devices are produced both in Russia and abroad.

In domestic conditions, modular circuit breakers, small and light, are most often used. They got the name "modular" due to their standard width, which is 1 module (1.75 cm).

In order to protect the electrical circuits of buildings, the following types of switches are installed:

RCDs, as residual current devices are abbreviated, prevent electric shock to a person who has touched the conductor, and prevent the surrounding objects from igniting when electricity leaks, which can occur if the cable insulation is damaged.

Circuit breakers protect circuits from short circuits and allow you to turn the power on and off manually. The most perfect protective device is the differential machine. It combines the capabilities of a residual current device and a conventional circuit breaker. This bag is equipped with a built-in protection against too powerful electron flow. It is controlled by differential current.

In single-phase power networks, single-pole and two-pole machines can be installed. The choice of a bag is influenced by the number of wires in the electrical wiring.

Before considering the procedure for connecting circuit breakers in an electrical panel, let's figure out how they are arranged and on what principle they operate.

The product includes the following elements:

• Frame.
• Control system.
• Top and bottom terminals.
• Switching device.
• Arc chamber.

Flame-resistant plastic is used as the material for the body and control system. The switching device consists of moving contacts, as well as fixed ones.

An arc chute is installed on a pair of contacts, which are the pole of the bag. When the contacts break under load, an electric arc occurs, which is extinguished by the chamber. The latter consists of steel plates, isolated from each other and located at the same distance. The plates of the chamber contribute to the cooling and extinction of the electric arc that appears in case of malfunctions. Automata can have one, two or four pairs of contacts.

Bipolar automata have two pairs of contacts: one is movable, the second is fixed.

Such a switch is equipped with a position indicator, which makes it easy to know whether the machine is on (red light) or off (green).

Visually the principle of operation of circuit breakers on the video:

To turn off the machine in case of emergencies, the device is equipped with a release. There are several types of these mechanisms, structurally different from each other and operating on different principles.

Structurally, this element includes a plate pressed from two different metals with an unequal coefficient of non-linear expansion, which is connected to the circuit under load and is called bimetallic. During the operation of the release, the flow of electrons passing through the plate heats it up.

Since the coefficient of expansion of the metal is less than that of the plate, it bends towards it. When the current rating exceeds the allowable value, the curved plate, acting on the trigger, turns off the machine. If the ambient temperature deviates from the norm, the switch also trips.

This type of release is a coil, which includes an insulated copper winding and a core. Since a load current flows through it, it must be connected to the circuit in series with the contacts. If the load current exceeds the allowable rating, the core will move under the influence of the magnetic field of the release and, by means of a disconnecting device, will open the contacts of the bag.

These devices are equipped with a special panel on which the time for switching off the machine is set. They provide a time delay in the event of a short circuit, which allows, in the event of an emergency, to turn off the emergency section without interrupting the power supply to the object.

A circuit breaker without a release is called a disconnector.

Before starting the installation of protective circuit breakers, you need to select them, as well as understand the intricacies of connection. People who want to know how to wire a circuit breaker ask various questions. For example, before or after the meter are the machines connected in the switchboard? Should there be an automatic input? These and other connection nuances are of interest to users.

Protective features include:

• Rated current value (in Amperes).
• The operating voltage of the mains (in Volts).
• Maximum short circuit current.
• Limit switching capacity.
• Number of poles.

The limiting switching capacity is characterized by the maximum allowable value at which the switch is able to operate. The PDR of household devices can be 4.5, 6 or 10 kA.

When choosing, they are most often guided by such basic indicators as the tripping current during short circuit, as well as the overload current.

The cause of the overload is the connection to the power grid of devices with an excessively high total power, which leads to an excess of the permissible temperature of the contact connections and cables.

Given this, it is necessary to install a packet in the circuit, the value of the tripping current of which is not less than the calculated one, but better - if it slightly exceeds it. To determine the rated current, you need to sum up the power of the devices that are supposed to be connected to the circuit (for each of them, this indicator is available in the passport). The resulting number must be divided by 220 (the standard voltage value in a household network). The result obtained will be the magnitude of the overload current. It should also be borne in mind that it should not exceed the current rating that the wire can withstand.

The magnitude of the tripping current during a short circuit is an indicator at which the circuit breaker turns off. The calculation of the short-circuit current is carried out when designing a line according to formulas and reference tables, as well as using special equipment. Based on the obtained value, the type of protection is determined. In small objects and in domestic networks, automatic machines of type B or C are used.

First of all, you need to decide on the connection of the power wires, and only after that figure out how to connect the machine to the network. If you do not know whether the supply conductors should be connected to the top or bottom of the bag, refer to the requirements of the Electrical Installation Code, which are the main guiding document for electrical work.

The Rules clearly state that the power cable must be connected to fixed contacts, and this requirement must be met in any scheme for connecting circuit breakers. In any modern device, the fixed contacts are located on top.

For installation, you will need control devices and tools, which include:

• Mounting knife.
• Screwdrivers (cross and slotted).
• Multimeter or indicator screwdriver.

So, how to connect the machine correctly? Consider the installation of circuit breakers in single-phase networks.

Two-phase and three-phase connection is more complicated and it is desirable that it be carried out by a specialist.

The installation is carried out in a network where two cables are used to perform the input: zero (PEN) and phase (L). Such a system exists in old buildings. The supply conductor is connected to the input terminal of the machine, then it passes through the meter from the output terminal, after which it is routed through the protective devices of specific groups. The power supply cable is also connected to the PEN through an electric meter.

The use of one, two and three-pole machines on video:

We consider the installation of a protective device in a single-phase network, where three conductors are used for input: phase, zero and ground cable. The input terminals, marked on the device with numbers 1 and 3, are located at the top of the machine, and the output terminals (2 and 4) are located at the bottom.

The power cable is connected to the input terminal 1 and securely fixed to it. Similarly, the neutral wire is attached to terminal 3. The phase passes through the electricity meter. The power is evenly distributed among the switch groups. From terminal 4, the neutral cable is connected to the N bus, passing through the meter and the RCD.

A passport is attached to any circuit breaker, which describes how to properly connect the wires to its terminals. The document contains all the necessary information - from the cross-section of cables and the type of their connection to the length of the stripped part of the conductor.

The ends of the wires for connecting household machines are stripped with a mounting knife by about 1 cm. You can distinguish the conductors by their color marking:

• Phase cable - white or brown.
• Zero wire - black, blue or blue.
• The ground conductor is green.

After stripping the end of the wire with a knife, it must be inserted into the contact clamp and secured with a fixing screw. The screws are tightened with a screwdriver. After fixing the wire, you need to pull a little to make sure that the fixation is secure. If a flexible wire is used to connect to the bag, then special lugs should be used to increase the reliability of the connection.

In order for the installation of machines in the electrical panel and the connection of cables to them to be carried out correctly, you need to remember common mistakes and avoid them during operation:

• Contact of the insulating layer under the contact clamp.
• Too much tightening force, which can lead to deformation of the body and, as a result, to breakage of the machine.

Often, several protective devices are mounted in the switchboard at once. To connect them, inexperienced specialists use jumpers.

In principle, this is not a mistake, but still in this case it is better to use a special tire cut to the desired size - the so-called comb. With its help, the wires are connected to the bags in the desired sequence.

Self-supporting insulated wire is widely used to transmit electricity to the home network from overhead power lines instead of a conventional cable. With all the advantages of this conductor, the connection of the SIP to the circuit breaker should not be made directly, since during operation the aluminum begins to “float” and the insulation burns. Ultimately, this leads, at best, to the failure of the machine, and at worst, to a fire. The easiest way to avoid such a nuisance is to connect the SIP to the machine through a special adapter sleeve.

Such a device provides a transition from aluminum wire to copper. You can buy it in a specialized store.

Step by step installation of the machine - on the following video:

In this article, we dealt with the question of how to properly connect circuit breakers in an electrical panel, and also examined the varieties of these devices and the features of their work. Using the information provided, you will be able to independently install the package and connect it to your home network. Naturally, with this procedure, you must strictly follow the rules of electrical safety, as with any work related to electricity.

Today, electricity is the main source of energy and is used in almost every home. But before you connect to the mains, you need to install a so-called metering device - an electric meter. The easiest way, of course, is to make an application to the same RES, according to which the meter will be installed by specialists. But the application costs money, and the entire installation can be done independently, since the connection diagram of the electric meter is quite simple.

Classification of electricity meters

Before installing an electric meter or replacing an old model with a new one, the device must first be selected and purchased. But in order to make the right choice and not throw money away, you need to have a good idea of ​​what electric meters are and how they differ from each other.

According to the principle of operation, the devices are divided into three types:

Functionality of different types

The main disadvantages of induction devices are low accuracy and poor protection against fraud (theft of electricity). In addition, they are afraid of dust, require strictly vertical installation and need frequent verification. Due to the simplicity of the design of the product, these single-rate and do not have remote control, but mechanical electricity meters are reliable, durable - there is simply nothing to break in them - and they are quite inexpensive. To date, induction metering devices are considered obsolete and their production has been discontinued.

Fully electronic and electro-mechanical devices, although they are much more expensive than induction, are distinguished by high accuracy, reliable protection against sabotage and wide functionality. They can support several tariffs (up to 4 or more), allow you to read readings remotely, work in any position and are not afraid of vibration.

The only thing is that the display of the electronic type does not tolerate sub-zero temperatures - it simply “goes out”. It is for this reason that in cold regions and when installed outdoors, unheated private houses and garages, experts recommend using electronic-mechanical models.

Electric meters of all types are available in single- and three-phase versions. Three-phase devices have the same principle of operation as single-phase ones, and can control the consumption of electrical energy simultaneously in all three phases, although they are also fully operational in single-phase networks.

How to connect the meter yourself

Installed and connected multi-phase electric meter

And connecting it is not much more complicated and the connection requirements are the same: do not get under voltage, do not mix up the wires and securely fix the device, protecting it from dust and moisture:

Wiring diagram of a three-phase electric meter

Connecting an electricity meter with current transformers

Wiring diagram of a three-phase meter through current transformers

In this scheme, the electric meter is connected not to a break in the network wires, but to the secondary windings of the CT, which are designated as I1, I2. And the primary windings of the transformer are connected to this very gap (in the diagram L1, L2).

Before undertaking the assembly of the above circuit, it is necessary to clearly understand several issues. Not only the safe and long-term operation of the circuit, but also its performance will depend on their correct solution. Here are the main ones:

1. Correct selection of wire cross section.
2. CT coil phasing.

If you are not cutting the CT directly into the line, then the primary connecting wires must have the same gauge as the line wiring. The conductors connecting the CT and the meter, of course, can be thinner, but they must confidently withstand the current indicated on the meter case.

This meter can withstand a maximum current of 7.5 A, which means that the wires for connecting it must be selected with the appropriate section

Particular attention should be paid to the phasing (correct connection of the ends of the coils) of the CT. Otherwise, the meter will either not work, or will lie, or even spin in the other direction if it is bidirectional. How to deal with phasing? The figure below will help with this:

A set of current transformers for a three-phase network

Even if your transformers are not quite similar to those given, there is not much difference - in any case, all winding terminals are marked in the same way. The contacts of the primary, power winding are easy to distinguish - they are much more powerful than the contacts of the secondary and are located on opposite sides of the product. They are marked L1 and L2. The outputs of the winding 2 connected to the electric meter are closed with a transparent cover in this embodiment and are designated I1, I2. If you look at the connection diagram of the meter, you can see that the coils must not only be connected to each in its place, but also correctly phased:

• L1 - to the input of the supply line;
• L2 - output to the load;
• I1 - to enter the counter;
• I2 - counter output.

As for the color of the TT case, it is conditional and serves only for ease of installation. In fact, all three transformers are absolutely identical.

What if your house has a single-phase network, but the current consumption is too high for the electric meter? This situation is quite rare, but it happens. And here the current transformer will help out, and only one . How to connect a single-phase electricity meter through a CT is clear from the figure below:

Connection diagram of a single-phase electric meter with a current transformer

Inclusion in the scheme of protection systems

The electric meter is just a metering device and has no protection against an emergency situation. It will easily burn out when the network is overloaded, it will not protect equipment during overvoltage, it will not save people in case of insulation breakdown and equipment failure. That is why all metering devices are supplemented by certain protection systems. The main and most necessary of them are:

1. Leak current protection.
2. Overload protection.

To perform the first tasks, the so-called differential switches or RCDs are used - Emergency Shutdown Devices. The task of overloading is solved by conventional fuses (plugs) or circuit breakers, referred to in everyday life as "automatic devices". They are usually made as separate devices, but often RCDs and automata are combined in one housing (differential automaton).

Circuit breaker (left), RCD and differential circuit breaker

Connecting an RCD and an automatic machine is no more difficult than installing a meter, but some questions still require clarification.

Where to put the machine - before or after the counter

In principle, both the counter and the protective device do not care at all in what sequence to stand. If, for example, a short circuit occurs, then the overload current in the entire line will be the same. More importantly, the circuit breaker will immediately break the circuit, saving the line itself and the devices connected to it.

Another thing is that the automatic machine can de-energize the line located behind it manually. This can be useful, for example, during maintenance and repair work. Here, no doubt, installing a machine in front of the electric meter would be more convenient, but not all electricity suppliers welcome this, fearing unauthorized connection. Therefore, before putting the switch in front of the meter, ask your RES if it is possible to do this.

Can multiple machines be installed?

Not possible, but desirable. This will make using the home network not only safer, but also convenient. If, for example, sockets and lighting are wired to different machines, then in the event of a short circuit, say, in an electric stove, only the machine responsible for the sockets will work. This will allow you to use the lighting when troubleshooting..

Where to put the leakage protection

With RCDs, in principle, the situation is the same as with automatic machines. If, God forbid, a leak occurs, then the RCD will work great, being installed both before and after the electric meter. In practice, differential switches are more often placed after metering devices - no one needs to ask permission for installation. As for the installation of several differential switches, each on its own line, there are no restrictions here either.

Well, now is the time to see how to connect a single-phase electricity meter and circuit breakers:

Scheme of including the meter and machines in a single-phase network

For three-phase circuits, the circuit will be almost the same. The only thing is that for its implementation you will need equipment designed for multi-phase networks:

Scheme of including the meter and automatic machines in a three-phase network