Shield for electricity meter. Distribution boards and boxes, terminal blocks, accessories

An important part The power supply system includes an electrical panel for the meter and automatic machines. It is with the determination of its location that planning or modernization begins electrical networks. The device is a distribution box used to monitor and manage all electrical wiring lines. Therefore, it is so important to choose and install it correctly.

An electrical panel is a distribution box, designed to accommodate input devices, protection elements and an electricity meter. This box is used both at production facilities and in private houses and apartments. IN technical documentation You can also find another name for it - distribution point.

In fact, the device is a box with seats for fastening electrical fittings. Its design includes a door designed not only to protect the equipment located in the cabinet, but also to prevent electric shock. Depending on the purpose, shields produced by industry can be:

Thus, electricity is supplied to the socket or lighting groups from the switchboard. All necessary electrical equipment is installed in the floor or apartment unit, for example, package circuit breakers, RCD, voltage relay, input differential circuit breaker, zero and grounding voltage block. In addition, an electricity meter can be mounted in it.

Requirements for various types shields are the same. They are designated in the operating rules for electrical installations (PUE) and GOST 51321. The main contents of these documents are as follows:

Types of shields

The division of panels according to purpose is conditional and is intended to be indicated on building plans or in other documentation understandable to specialists. For consumers, electrical cabinets are divided according to other criteria. First of all, this includes installation, which can be built-in or wall-mounted.

The built-in (internal) structure looks more attractive, since it forms almost one whole with the wall on which it is placed. The second type is hung using fasteners, which allows it to be used even on thin partitions. It should be noted that there is also a shield floor type, made in the form of a cabinet and used only in production.

In addition, electric boxes vary in size and material from which they are made. Metal or plastic is used as a base for them. There is no fundamental difference between the use of one material or another, but for built-in or outdoor use it is recommended plastic box, although the metal one is vandal-proof and has a lock.

All shields have their own markings, consisting of letters and numbers. So, ShchKU means apartment metering panel, ShchKR means distribution panel, ShchRV means internal, and ShchRN means mounted. The number after the abbreviation indicates the number of modules that can fit in the device. For example, the marking ShchRN-10 means that the electrical cabinet is intended for wall-mounted design and is designed to install ten modules.

There are also models that have a mounting panel. They are designated SHMP. Due to their small dimensions and good appearance, they can be used both in floor niches and in apartments. The difference between outdoor devices (SHRNM) is the ability to remove the mounting panel, which allows you to increase the useful volume of the box.

Characteristics of distribution blocks

The technical parameters of distribution boxes for electrical machines are related to ergonomics and the number of simultaneously installed modules. Thus, the quality of the device depends on the accuracy of the fit of the elements, the type of materials used in the manufacture and the coating of the metal parts. The following design characteristics are distinguished:

1. Dimensions. Indicated in millimeters. Most often, the electrical panel is made in a rectangular shape.
2. Number of modules. Indicates the number of seats for electric machines. It should be noted that some devices, for example differential automatic machines, can occupy more than two places. Unit of measurement - pieces. Additionally, space may be provided for installing an electricity consumption meter.
3. Material. Shields are made of metal or non-flammable plastic.
4. Place of use. There are options for outdoor and indoor execution.
5. Door type. If the electrical panel has a door, then it can be transparent or solid. Executed from sheet metal or plastic and can be supplemented with a fire-resistant seal, as well as have a latch or a full-fledged lock.
6. Installation type. May be three types: mounted, built-in, floor-mounted.
7. Level of protection. This value corresponds to the standard international classification. It is characterized by an IP protection system, which determines the degree of withstanding the impact of solid objects and water, and IK, indicating resistance to impacts (the more, the better).
8. Color. Available in various color scheme, may have the texture of wood or other decorative material.

Nuances of choice

In retail outlets, electrical panels are presented in large assortment. They are produced by almost all leading manufacturers of electrical accessories. Most often, electricians choose shields such brands, like Schneider Electric, Hager, ABB, Legrand, Viko, IEK, Makel (the last 3 are the most budget options).

Before purchasing a device, you will need to decide where the box will be located and what electrical accessories you plan to install in it.

Wall-mounted cabinets allow safe electrical installations and are primarily intended for installation in wooden houses or on walls where it is difficult to create a niche. Built-in boxes fit perfectly into the interior and are used in corridors intended for emergency exit.

If you plan to purchase an apartment built-in electrical panel, then you should clarify the issue of installing an electricity meter. Since the consumer does not have the right to disconnect and switch the meter, he will need to call an electrician before moving it into the box. To avoid this, you can purchase a small box for your home. On average for three-room apartment A box designed for 12 modules is enough, taking into account the fact that the introductory machine takes up two seats.

In case of a planned replacement or relocation of the meter, you can buy a combined cabinet. The location of all distribution elements in one place will look more harmonious. At the same time, it will be more convenient to commute them with each other. It is desirable that there is a slot in the closing door through which it is convenient to take readings from the metering device. It’s even better if the electrical panel is equipped with a transparent door. It will allow you not to open the box every time to assess the position of the circuit breakers.

For household and administrative buildings The protection class of the shield must be at least IP31, for production - IP54. An outdoor shield located in an open area must have a protection class of IP55 and higher. The dimensions of the electrical panel depend on the types of modules installed in it and their number. Most often, devices with a depth of 120 mm are chosen for the home.

Installation and assembly

The assembly of an external or internal structure is not fundamentally different from each other. But in the second case, you first need to make a niche into which the grooved channels for laying the electrical wire will fit . Any electrical cabinet consists of several parts, which include:

• base of the shield;
• place for laying the electrical cable with its holders;
• racks for fastening terminal blocks;
• din rail.

Depending on the model, a door, protective cover or lock may be added.

Direct installation involves mounting the box in the designated place. But before this, depending on the side of the cable plant, a plug is broken off in the shield. Electrical wires are inserted into the resulting hole. The external box is hung on a pre-installed installed bracket. There are also models that are attached with screws; for this, they are screwed through the back panel into the installed dowels.

The internal box for electric machines is inserted into the niche and secured using solutions on gypsum base. Before fixing it, pass all the wires through the prepared holes. As soon as the cabinet is fixed, the installation of electrical appliances begins.

First, screw on the DIN rail and the electric meter, if its installation is provided. Then the grounding and grounding buses are installed. Circuit breakers, residual current devices (RCDs), differential circuit breakers and other protective equipment are placed on the rail. Installing them is easy thanks to a specially spring-loaded latch that firmly presses the electrical accessories to the DIN rail. As long as the mounting screw is not tightened, the installed device can be easily moved horizontally.

As soon as everything necessary devices will be placed, proceed to connecting the wires. To perform these steps without errors, it is convenient to use a pre-designed wiring plan. It is recommended to observe the color of the wires when making connections. So, a wire is connected to the zero bus blue, grounding is done in green, and brown is used as phase.

Models of electrical panels are not tied to manufacturers of modular elements; for example, a Hager electric machine can be installed in an ABB case without any problems. Therefore, their functionality is determined by ease of installation and protection class. Among the many products produced, some models are especially popular for installation in apartments. But if in industrial buildings The main criterion is reliability, then in apartments it is aesthetics.

For hidden installation It is recommended to purchase the Hager Cosmos VR118TD shield. Its door is made of transparent plastic; if desired, it can be easily removed from its hinges. Opening direction is up. The box is equipped with grounding and zero busbars made of brass. The degree of protection corresponds to IP 31. The number of installed modules is eighteen. This shield is distinguished by its beautiful appearance, ease of installation and low price.

If necessary outer shield, you can purchase the VIKO LOTUS model. This inexpensive model will be especially relevant for residents of Khrushchev-era buildings. It allows you to accommodate twelve modules. The kit contains tires, all necessary fasteners and a DIN rail. White The product and its darkened door are suitable for any interior.

Building a power supply system without using electrical panels almost impossible. Their installation not only makes it convenient to turn on and off the power supply on certain lines, but also increases the safety of using the power network as a whole. At the same time, boxes for placing meters and electrical modules come in different placements and can be selected to suit any interior.

Accounting board electricity. What kind of shield is this and what is it for? Actually, as the name suggests, this is electricity metering panel, i.e. shield where it is installed.

You can order the assembly of an electrical metering panel from me.The price of a metering board starts from 9,000 rubles.
Assembly time from 1 week.

In the article we will look at what elements (devices) the metering board diagram and examples consist of.

Depending on the number of connected phases from the overhead line, the voltage metering board is divided into metering panel 380V and 220V, i.e. three-phase or single-phase. In accordance with the number of phases, either a three-phase or single-phase electricity meter is installed in the metering panel.

The metering board is usually installed for private houses. For apartments, meters are installed either in floor panels on landing or in apartments in a common panel. It is assembled according to technical specifications (specifications) issued by the network company to whose electrical networks you are connected. Usually these are familiar to many: Mosenergo, Lenenergo, Kurskenergo and other “-energos” by region.

IN recent years network company requires installation of metering panels (MCB) behind the fence in an accessible place so that the metering board is visible and there is no opportunity for theft of electricity.

Therefore, it is correct to install a metal metering board so that it is not broken on occasion, although this does not always help. It is also important that the metering board is high (at least IP54), and, ideally, climate version U1 (for installation outdoors at temperatures from -40 to +40 degrees).

The body of the metal shield must be connected to the grounding device, and if there is a electrical appliances, for example, signal lamps, then the switchboard door in mandatory also grounded.

The metering board is usually installed on a power line pole (support), a separate pipe stand, on a fence, or on the facade of a house. The installation location must be agreed upon with a network organization, the chairman of SNT and other societies, otherwise they may not be accepted.

The height metering board is usually mounted at eye level 1.6-1.8 m above the ground, but sometimes, as in one of the photos, it has to be installed quite high. This is due to banal vandalism.

Network organization often requires that the metering board had a viewing window for taking electric meter readings. Unfortunately, this makes serious adjustments when choosing such a metering board, because... There are no high-quality metal metering panels with a viewing window; manufacturers such as ABB, Legrand and Schneider Electric simply do not make them. And shields from IEK, EKF and other Chinese - Russian manufacturers, lose appearance and rust after a couple of years of use.

Shield accounting. Scheme.

The metering board circuit can be divided into two components: the grounding system and the electrical circuit.

Grounding system. Whether it will be TN-C-S or TT depends on a number of conditions (the condition of the line, the distance of the transformer, the presence of repeated groundings on the line, from which wire the line is mounted). I do not consider other grounding systems (TN-S, TN-C, IT).

The most common grounding system for a private home is the TT, because large number Power lines of electric networks are still made “bare” aluminum wire and it is impossible to make TN-C-S.

An example of a CT grounding system and metering panel assembly is below.

A metering panel with a grounding system is more difficult to assemble. Firstly, as I wrote above, the electrical network must be in proper condition. Secondly, taking into account the requirements of the network organization to have a switchboard with a viewing window, the choice is seriously limited, and in such switchboards it is sometimes problematic to perform a high-quality separation of PEN into PE and N. But here the RBP-95 terminal block helps constructively.

An example of the TN-C-S grounding system and metering panel assembly is below.

Electrical diagram metering board, as I wrote earlier, depends on technical specifications, which were issued to you by the network organization.

The simplest metering panel consists of an input machine and a meter, to which the input cable is connected to the site or house. But such a scheme has an obvious disadvantage, if, for example, something happens to the cable, then when replacing it, you will have to tear off the seal from the meter, which means calling and waiting for an employee of the organization that installed this seal, otherwise, if you break it yourself, it will serious fine. Therefore, it is better to install another machine after the meter, to which the cable will be connected, and even better, install a selective fire protection RCD.

It is better to install the input machine in front of the counter in a special box, so that the network company can seal it in order to prevent the connection of cables to the meter for theft of electricity.

Also, it would definitely not be out of place in the metering panel surge suppressor (SPD) or protection device surge surges(SPD), which will protect your equipment from impulses of several thousand volts arising from atmospheric (lightning) and switching overvoltages. The device is not cheap and costs several thousand rubles.

Often the network in TU prescribes in mandatory conditions installation of an SPD, and if you have signed the specifications, you will have to install an SPD. If the specifications have not yet been signed, then you can write a reasoned refusal, in which you indicate that such a requirement to install an SPD is illegal and does not apply to individuals, as well as the Electrical Installation Rules (PUE) themselves. In such cases, the network removes the clause on SPD from the technical specifications or transfers it to recommendations. But, I repeat, SPD is enough useful device, and if you have the financial opportunity, then install it without hesitation.

It is best to install the SPD in the metering panel in front of the meter, because Most meters are electronic, and often fail after a thunderstorm. If you install the SPD before the meter, then, just like the input machine, install the SPD in the box for sealing.

If you are just starting to build a house, then a metering panel will definitely not hurt you 220 V socket, and it must be protected automatically and .

I additionally complete metering panels good seals (pressure seals), because The factory ones that come with the kit are of extremely low quality.

Accounting board. Price.

Shield cost accounting in a minimum configuration of budget components, taking into account assembly, will be approximately 9000 rubles:

• body (metal shield).
• three-phase input circuit breaker.
• single tariff electricity meter.
• three-phase automatic machine for cable connection.
• box for sealing the introductory machine.
• ground terminal.

Hello, dear friends and colleagues! We present to you assembled and ready for shipment. street electricity metering panel with degree of protection IP54 for installation on a pole or support.

Purpose of the control room

Street electricity metering panel designed for electricity metering and protection of electrical equipment from overloads and short circuits on the outgoing line in networks with a solidly grounded neutral at a voltage of ~380/220 V AC frequency 50 Hz.

Next, “Street metering board”...

Street metering board designed for installation on a pole or support, it can also be mounted on external wall buildings. The electrical panel has a degree of protection IP54 - thereby protecting the electrical equipment installed inside the electrical panel from dust and moisture.

Design features of the control room

Electrical panel housing made of sheet metal and has a mounting plate for mounting one or more three-phase meter, as well as automatic switches to protect electrical equipment from overloads and short circuits.

• On back wall The housing provides four independent fastenings for installing the electrical panel on the wall - thus: the degree of protection IP54 is not violated!
• The metering board has a protective panel from accidental contact with live parts of the outgoing line.
• On the door The electricity metering panel has a viewing window for taking readings from the electricity meter.

Appearance

Conditional elements in the diagram

In fact, the metering cabinet was made to order using an individual electrical circuit. If you need a slightly different configuration and configuration of the electrical panel, call us! or send us an application with attached electrical diagram, through the application form on our website.

We don't want to offend anyone!

These examples are here only so that you can compare our build quality with the quality of other electrical panel assemblers!

How do you like the quality? did you like it? want a little bit cheaper? like third party manufacturers latest photos, alas... We don’t know how to collect!

This type of device is designed to receive and subsequently distribute electrical energy in various circuits. Distribution cabinets are classified into several types.

Usually cabinets are marked with the letters "shr". They are used in networks with a rated current of 400 amperes and a rated voltage of 380 volts with an alternating current frequency not exceeding 50 hertz. In addition, they highlight separate species distribution cabinets for use in networks with a voltage of 660 volts.

The marking "shrn" means that distribution cabinet is wall-mounted. Typically, the capacity of such cabinets varies from two hundred to one thousand two hundred bar. These types of cabinets are equipped with special frame fastenings, where the plinths are subsequently mounted.

The marking "pr" means "distribution point", this type of cabinet is used for distribution electric current in networks with voltages up to 660 volts and with frequencies varying from 50 to 60 hertz. distribution points also serve to ensure the safety of electrical networks and prevent short circuits and random overloads.

Another type of wall cabinet (“shrn”) is wall-mounted. It should be highlighted separately, since increased requirements for strength and reliability apply to its design. Often such cabinets are made of metal and are reliable and durable.

At the entrance to the internal network of an apartment, house or cottage, an apartment distribution board (ASB) is almost always installed, which houses an electric meter and circuit breakers (AB) and other equipment. Let's look at the functional purpose of this device, it design features, installation and connection rules.

Functional purpose

Any switching device must have appropriate protection that prevents contact with live elements and prevents foreign objects from entering them that could cause a short circuit. In addition, electrical devices are installed in the control panel that perform the following functions:

• accounting for electricity consumption;
• protection of the internal network from overload and short circuit;
• manual shutdown of any of the internal lines, for example, for repair work.

Design and performance features

The control panel is a plastic or metal box equipped with a door, inside of which there are special seats for a meter, AV and other equipment.

Designation:

• A – body made of non-flammable plastic or metal;
• B – lockable door;
• C – viewing window for taking readings of the electric meter by employees of the control service;
• D – mortise lock;
• E – mount for metering device;
• F – Din rails, which are a standard profile on which equipment is installed (AV, RCD, zero bus, etc.);
• G – panels that block access to live parts of installed electrical equipment.

There are two types of housing design - for external and internal installation.

The size of the box depends on the estimated number of installed modules.

Another factor influencing the design of the electrical panel is the protection class. Below is a table deciphering the accepted designation in accordance with certain operating conditions.

For example, we have a control panel with protection class IP65, according to the table above, this parameter indicates that with this design, dust and splashes of water are guaranteed not to penetrate into the structure (provided that the door is closed).

What to look for when choosing?

When choosing a control panel, you should be guided by the following factors:

1. Housing mounting method. If you plan to install on concrete wall panel house, then preference should be given to a box designed for wall-mounted. Otherwise, there is a high probability of integrity violation load-bearing wall. In addition, the installation process itself will be significantly more complicated.

Accordingly, when installing into a hollow wall, for example, a plasterboard partition, a built-in structure is selected.

1. Estimated number of units. Their number is determined characteristic features electrical wiring. As a rule, each line is connected to a separate protective device. It is recommended to leave a reserve of 20-30% in case of possible modernization of the internal network in order to connect any electrical appliances, such as an air conditioner or boiler. Replacing a control panel requires more effort than installing another AB module.
2. Selecting a protection class. It is determined depending on the operating conditions. If you plan to place it indoors, you can limit yourself to categories IP30-40. The external electrical panel requires a higher protection class (IP44-65).
3. Choice of material. Here you should also be guided by the location. If the panel is supposed to be installed inside a residential building, then, from an aesthetic point of view, a plastic case is preferable. Metal boxes are more suitable for a garage, workshop or other utility room.

The correct choice of switchboard is very important, since after its installation and connection it is not possible to quickly replace the electrical panel.

Since the shield relates to electrical equipment, it must be accompanied by a technical passport, which reflects the following information:

• model name;
• manufacturer information;
• technical parameters (permissible voltage, current and frequency) and technical specifications code;
• assigned protection class;
• production date.

The absence of a passport indicates that the product is most likely counterfeit, and its technical specifications may not meet standards. For example, non-fireproof plastic was used in production.

Choosing an installation location

In a residential area, it is advisable to set aside a single area to accommodate devices that provide connection to external telecommunication networks and a power source. The centralized location greatly simplifies the maintenance of these systems. As a rule, a place is allocated for such a zone inside the apartment near the entrance. IN panel houses There are special niches in the vestibule room.

If external installation is carried out, then a base made of non-combustible material must be placed under the control panel box.

The bottom edge of the box must be at a height of at least 100 cm from the floor level, while upper part the building is limited to a height of 180 cm. This range can be reduced to 50 cm and 130 cm (respectively) if disabled people or elderly citizens live in the apartment.

• in a hazardous area classified as “0”, “I” and “II” (showers, bathrooms, etc.);
• in interior items and furniture (for example, a closet or wardrobe);
• above heating installations;
• near plumbing fixtures;
• above a gas or electric stove;
• outside the house (the restriction does not apply to metering panels);
• on loggias and balconies, including glazed ones;
• in the bathroom;
• on a flight of stairs;
• in any damp room;
• in the ventilation shaft.

Example of internal wiring

Let's take as an example the wiring diagram for the switchboard of a one-room apartment.

Designations:

1. Bipolar AB. Through it, a connection is made to an external single-phase source (220 volts).
2. Metering device.
3. Residual current device (in this case it is common to all three lines).
4. Zero distribution bus.
5. AB for lighting.
6. AB to sockets.
7. AB to a separate power line for the electric stove.
8. Ground bus.

The diagram shows the ratings of AB and RCD, and also shows the wire cross-section. Information on how to choose the right elements can be found on our website.

Selection of equipment for control panel

When selecting electrical devices and cables, you must be guided by two criteria:

1. Technical parameters.
2. Manufacturer reliability.

If to determine technical parameters It is enough to carry out a few simple calculations, but when choosing a manufacturer, not everything is so simple. Many inexpensive counterfeit products have appeared on the market. In addition, there are often outright fakes famous brands. Therefore, we recommend checking that electrical devices have the appropriate certificates. This is especially true for metering devices. Any electricity supply company will refuse to connect an uncertified meter, as well as a device that has not passed verification.

For all internal switching of the control panel, it is recommended to use solid-core PuV wire. It is allowed to use a multi-core analogue - PuGV, provided that the twisted wires at the ends are crimped with special lugs. The insulation of wires of these brands is made of non-flammable material and retains its properties in the temperature range from -40°C to 75°C. The service life of such wires is at least 15-20 years.

To supply phase to the input of automata, you can use special element“comb”, it is used as a distribution bus.

To conclude the topic, we will offer a few tips that will help you assemble a panel for an electric meter and machines without making serious mistakes:

• It is not allowed to run a wire or cable under the AB fastening profile;
• when tightening the clamps, the magnitude of the applied torque should be in the range of 2.5-3.5 Nm;
• if the box is made of metal, it must be grounded;
• the length of the supply of connected cables should be one and a half to two times greater than the height of the control panel, but not exceed 400 mm;
• All internal switching lines must be marked; this requirement also applies to installed electrical equipment. Below them, or on the door, there should be a table indicating the purpose of each element.