Connection diagram for a three-phase direct meter. Three-phase electricity meters: options, methods

An electric meter is a device whose main function is to measure the amount of consumed energy of an electric current.

Before you start connecting the electricity meter, you need to make sure that you have all the necessary components:

The device itself, the type and model of which fully corresponds to the expected load level.
Electrical panel or special box for installation. If it is already available and it is supposed to replace the old meter, then you need to make sure in advance that all fasteners are suitable for installation. Sometimes electrical panels are installed outdoors, in which case an IP protection level is required.
DIN rail, if the selected device is intended to be installed on it, and this element is absent in the electrical panel.
Additional modular equipment, which is necessary to ensure the protection of electrical wiring from fire and people from electric shock. Residual current devices are often referred to as such devices.
Special null buses for installation on a DIN rail, designed for distribution and switching of zero and protective zero. Usually they are included in the complete set of electrical panels, but in some cases their separate purchase is required.
Installation wire, without which it is impossible to connect and connect internal elements in the electrical panel. For such purposes, it is recommended to use a PV-1 mono-core cable made of copper.
Self-tapping screws, special plastic ties and dowels, without which it will be impossible to implement the fastening of the electrical panel, as well as the installation of DIN rails and zero buses inside it.
Heat shrinkable tubes and insulating tape, which will help when marking the cable, since PV-1 does not have any color coding.

In addition to the listed components, it is also necessary to prepare a number of tools, without which it will be impossible to install the meter:

Screwdriver Set different sizes and forms;
multimeter or special indicator screwdriver;
ruler or tape measure;
building level;
knife with a sharp blade;
nippers;
a set of pliers with different sizes;
puncher;
insulation stripper;
soldering machine;

Preparatory work

boxing itself

Before starting the installation and connection of the electric meter, it is necessary not only to prepare tools and accessories, but also to conduct a series preparatory work... First of all, it is required to install a special box, inside which all the equipment will be placed.

In fact, all modern models of devices that need to be installed are originally designed for mounting on a DIN rail, which will greatly facilitate the entire installation process.

Boxes are made from special types of plastics, which are necessarily fire-resistant; electrical panels may have a different number of places for installing such devices.

Their preparation for the installation process is one of the main stages of work preceding the installation and connection of the meter, this is done as follows:

Dismantle the top cover of the box, usually for this it is necessary to unscrew the fastening screws that hold it.
Install the box on the wall, in accordance with safety regulations, the height should be in the range of 0.8-1.7 meters.
Secure attachment of the device carried out using self-tapping screws, their variety is determined depending on the materials from which the wall is made.

After installing the box, you can proceed to the next process - installing the electricity meter.

Step-by-step installation instructions

The installation process of the electricity meter itself should be carried out in accordance with the following algorithm of actions:

Originally a circuit breaker with two poles is being installed. This can be done using a latch located on the back of the device. It is installed on one of the top DIN rails.
Similarly the installation of the meter itself is also carried out, in the design of which there is exactly the same special latch.
Installation in progress additional outgoing machines with one pole.

After completing these simple steps, the installation of an electric meter for consumed energy can be considered complete, followed by the final stage - connection.

Connection

single-phase meter connection diagram

The process of connecting the equipment may differ depending on the selected type of electricity meter.

In the case of using single-phase models, it will look like this:

Make sure in the absence of voltage and, if the old device is being replaced, eliminate it by first disconnecting all wires.
Carry out load cable entry and power supply from the common apartment wiring. If the electrical panel is installed outdoors, then it is additionally necessary to use glands that provide waterproofing at the point of entry of the wires.
Inserted cable length must be twice the required indicators in order to have a certain margin. In this case, it is necessary to avoid strong bends in order to prevent damage to the wires.
Insulating wires must be trimmed 10 mm. and part in different directions from each other. It may be necessary to momentarily turn on the voltage to identify the phase cables.
Lead-in cable must be connected to an appropriate circuit breaker.
To the top contacts wires are wound up: the phase is on the left, and the zero working cable is on the right.
Earthing cable connects to a special one in the electrical panel. After that, the initial tightening of the contacts and the control one are carried out, which is carried out after a few minutes. This measure is especially relevant if wires made of aluminum material are used for connection.
From the exit of the machine with two poles it is necessary to conduct a working zero and a phase wire directly to the electricity meter.
Single-phase varieties electric meters have 4 terminals, the connection to them is carried out in the following order: phase input, phase output, working zero input, working zero output.
Now you need to make jumpers from PV-1 to ensure the switching of all available modular equipment. To do this, you need to measure the distance between the terminals, and bend the cable at right angles with pliers so that it is securely fixed in the terminals of the equipment. For an electric meter, it will need to be cleaned by 27 mm., For all other modular devices, 10 mm will be enough. In situations where the phase must be distributed to several machines at once, a special comb is used.
Tighten all terminals, at first this process is carried out with the upper screw and, in case of secure fixation, the lower one is also tightened.
Connect the load to the machines, zero bus and ground bus.

After the steps have been completed, it is recommended to check the correct connection and secure fastening. Then a specialist is invited to put seals on the equipment and draw up a corresponding act.

The diagram for connecting three-phase meters will look differently. If this particular variety is used, then the following procedure must be followed:

Inside the electrical panel conduct a three-phase power wire with zero and a grounding conductor.
5 pins available, the connection is as follows: phase A is connected to the first, phase B to the third, and phase C to the fifth. Compliance with the phase sequence is especially important if an electronic meter is connected.
Phase output from the electric meter to the circuit breaker to consumers is carried out on contacts 2, 4 and 6.
Zero connects to the seventh and extends from it to contact 8.
Grounding conductor is attached and connected to the corresponding bus of the electrical panel. This is an important condition, since the disappearance of zero in electrical protection will cause a number of overvoltages, due to which consumers of electricity can fail.

three-phase meter connection diagram

Connecting three-phase meters is a much more complicated process, for which it is recommended that a qualified electrician is invited.

Contacts of modular electrical equipment

electricity meter contacts

In order for the electricity meter to be connected correctly and the device to function properly, it will be necessary to indicate the purpose of each of the contacts in the modular equipment used.

The first will be considered the meter itself, which has the following contacts in its design, if we consider them from left to right:

Connecting the supply phase.
Outgoing phase connection.
Connecting the supply zero.
Outgoing zero connection.

The contacts available on the circuit breakers have the following purpose:

Top pins of the input automaton are designed to connect the power wires coming from the apartment power supply network.
Bottom contacts of the input automaton are needed to connect outgoing wires to them, which are output to the electric meter.
Top pins for all outgoing machines with one pole, they are designed to connect the phase coming from the electricity meter.
Bottom contacts outgoing machines are designed for phase cables, the cores of which diverge in different directions.

All contacts have 2 special screws, which are necessary to ensure reliable clamping to the conductive cable. The quality of this process must be carefully monitored, since in the future seals will be placed on the equipment, and there will be no free access to the contacts.

Consequences of incorrect connection

The process of installing and connecting the electricity meter must be carried out exactly in accordance with the specified instructions in order to avoid the following undesirable consequences:

Short circuit, which causes instant failure and burnout of all electricity consumers that did not have grounding.
Overheating of electricity consumers, which can also suddenly disable them, causing breakdowns.
Spontaneous and at the same time incorrect connection electric meters is punished with fines by the responsible authority.

Often, the process of connecting such equipment is highly complex even in the presence of detailed diagrams and instructions, so it is recommended to entrust it to qualified specialists.

Which counter to choose?

Most often, the following factors influence the solution of this issue:

Equipment service life. Electronic meters are considered more preferable due to the peculiarities of their design and a number of other features. Manufacturers most often indicate in the technical manual an operational period of 15 years, but the mass production of this variety began not so long ago, so they have not yet had time to develop their potential. In turn, induction devices can maintain the accuracy of calculations and metering of consumed electricity even after 50 years.
Accuracy class. Devices with this parameter equal to 1 or 0.5 are considered the most effective and accurate, but for active use in a residential environment, a device with an accuracy class of 2 is sufficient.
Multi-tariff, but this opportunity has not been implemented in all regions of the country.
Availability of automated accounting capabilities is an undesirable feature, since it can only help energy companies, and the cost of such a device would be much more expensive than the standard version.
Large number of functions also affects the total cost of the electric meter, but in fact none of the people who have chosen such models use them in full.

Kinds

Today, there are many different classifications of these devices, one of the main ones is the type of electricity that it will take into account:

Induction meters

With one or three phases, are intended for accounting and control of the consumption of active and reactive types of AC energy.

Electrodynamic meters

Required for DC metering, which is used, for example, for the operation of electric transport or the corresponding types of railway communication.

Another factor by which these devices can be classified is the type of their connection:

Variety designed for direct connection to an existing power circuit.
A variety of transformer switching devices, for the functioning of which it is necessary to connect to the power circuit through a special one.

The third classification is the division of counters by measured values, according to which they are divided into the following types:

Single phase devices designed to work with alternating current 220V, 50Hz. All modern models allow this accounting method.
Three-phase devices, which operate in networks with an electric current of 380V, 50Hz.
A special kind of three-phase meters, which is capable of accounting for electric current with a voltage equal to 100V. They can only be connected to a high-voltage circuit with a voltage rating exceeding 660V and using special transformers.

The last classification is the division of devices according to the type of their design, in accordance with it, these devices are:

Electromechanical induction electricity meters, in which the stationary coils have an electromagnetic field that affects the moving part, which is a conductor. At its core, it is a special disc that is designed to pass currents through it. The number of revolutions made by the conductor during work is directly proportional to the amount of energy expended, thus, it is taken into account.
Mechanical induction electricity meters are a variety that today is used less and less and is replaced by other more modern models... This is due to the presence of a wide range of disadvantages, including one tariff, too large errors in the course of accounting, the impossibility of remote automatic recording of accounting data, the complexity of installation and use, an extremely low degree of functionality.
Electronic counter performs its functions due to the ability to convert analog signals into special types of pulses, the analysis and accounting of which allows you to calculate the amount of electricity consumed. Unlike induction devices, this type does not have rotating conductors or other similar elements in its design, which is their main advantage.

The shocking presence of many wires when connecting household electrical appliances always causes a headache. Complex and confusing connection schemes make you think: "Why does a three-phase meter have four wires?" To finally dispel all doubts, connect the three-phase meter with your own hands.

Why are three-phase electricity meters popular

Currently, in addition to traditional two-phase electricity meters, the popularity of three-phase meters has increased. This is due to the multifunctionality of three-phase meters, as well as the ability to somewhat reduce the cost of electricity consumption in everyday life.

In order not to be unfounded, we will suggest that when using a single-phase connection of a consumer of 20 kW, a cable with a large cross-section would be required. At the same time, load distribution is problematic to carry out, since one phase and zero will be involved. Three-phase connection solves such problems completely.

The need for a three-phase meter is due to the measurement of the values of active and reactive electricity. A distinction should be made between electronic active and reactive meters:
single rate active direct switching with accuracy class 1.0 and 2.0, equipped with an indicator
multi-tariff uni- and bi-directional.

Basic circuits for switching on three-phase meters

The three-phase meter connection diagram depends on the type of meter. However, three-phase meters support single-phase metering format.

Household three-phase meters are distinguished according to the connection diagram. It can be:

Direct connection counters
semi-indirect meters
indirect inclusion counters
counters taking into account the reactive component.

Direct connection meters

Direct (direct) connection meters are connected in the same way as single-phase meters directly to the 220/380 V network.

Direct-flow metering devices are designed for a current flow of up to 100 A., thereby limiting the use of an insignificant transmission power of up to 60 kW. Terminal block counters of direct connection and holes for wires are calculated for a small cross-section of wires. On average, this value ranges from 16 to 25 square millimeters. The direct connection diagram is the only one, its parameters are shown schematically on back side meter cover, so it does not cause difficulties when connecting.

How to connect a direct connection meter is shown in the video

Semi-indirect connection meters

Semi-indirect meters are switched on via current transformers. This allows metering of electricity with significant network capacities. In this case, when calculating the used electricity, the transformation ratio must be taken into account. The use of this circuit for connection is possible with the use of current transformers.

There are many semi-indirect inclusion schemes, among which the most popular are:
Wiring diagram for star-type current transformers
ten-wire circuit
connection diagram via test terminal box
with combined current and voltage circuits.
Most of the semi-indirect connection schemes are outdated due to the inefficiency of the element base.

The disadvantages of semi-indirect switching schemes is the complexity of verification by the controlling energy supply organizations.

Indirect inclusion counters

Counters for indirect inclusion for domestic needs are not of interest, because they are designed to meter electricity exclusively for high-voltage industrial connections 6 (10) kW.

The connection diagrams for the metering of the reactive component are not currently used.
The connection of a three-phase meter with indirect switching using current transformers is shown here.

How to connect a three-phase meter

Given the peculiarities of connecting a three-phase meter, it is preferable to entrust the installation and its installation to specialists from organizations that have a license granting the right to maintain electrical work... Moreover, registration of the installation of a new meter is carried out with the permission of such organizations.

If wiring diagram is not included in the delivery set of a three-phase meter, an installation diagram is drawn up. The meter intended for connection is checked for the presence of state verification seals on the fastening screws. State verification seals on three-phase meters must be 12 months old. It is necessary to check the integrity of the casing and glass on the meter body and the presence of fixing screws in the terminal box itself.
Before installing a three-phase meter, you must de-energize the apartment.
It is preferable to install and install a three-phase meter in a special cabinet, where protection and switching devices are additionally mounted. Mounting elements are mounted on a DIN rail. After fixing the wires of the electricity meter with the fixing screws, the system is checked for operability.

The most promising three-phase meters

Traditional schemes for connecting a three-phase meter to a 380/220 V network and meters are gradually giving way to more advanced electrical appliances.

Significant amounts of electricity consumed make you look at the use of three-phase meters in a different way. Let's not hide that modern cottages and apartments equipped with powerful consumers of electricity, such as saunas or integrated smart home systems, which need equal load distribution. Therefore, promising three-phase meters will reliably provide the required operating mode.
The existing three-phase electricity meters of the CE series can be safely called devices of a new generation. What is the difference between meters of this series from famous models? First of all, this is the extended functionality of a microprocessor-based multi-rate meter.

Electricity and capacity metering is carried out at several daily rates and provides for several tariffication schedules. “What's the trick?” You ask irritably. It's all about reprogramming. In this case, there is no need to replace and install a three-phase meter, it is enough to call a specialist who will reprogram the operating modes. The modern element base of the CE series three-phase meter allows metering of electricity from high class accuracy 0.5 - 1.0. At the same time, two levels of access, protected by a user password, exclude the possibility of unauthorized access and theft of electricity from outside. The range of operating characteristics (voltage) from -15 to + 20% of Un create normal conditions operability in intermittent modes and network loads.

Commissioning or reconstruction of electrical wiring in a house or apartment is rarely complete without installing or replacing an electric meter. According to the standards, work can only be performed by specially trained people who have permission to work in networks with a voltage of up to 1000 V. But you can install all the elements, connect the meter to the load (electrical appliances) without connecting the power. After that, it is necessary to call a representative of the energy supplying organization for testing, sealing and starting the system.

Meter connection: rules and basic requirements

Exactly all the requirements are spelled out in the PUE, and the basic rules are as follows:

Must be installed with weather protection. Traditionally they are mounted in special boxes (boxes) made of non-combustible plastic. For outdoor installation, the boxes must be sealed and must provide the ability to control the readings (have a glass opposite the scoreboard).
It is fixed at a height of 0.8-1.7 m.
The meter is connected with copper wires with a cross-section corresponding to the maximum current load (available in the technical conditions). The minimum cross-section for connecting an apartment electricity meter is 2.5 mm 2 (for a single-phase network, this is a current of 25 A, which is very small today).
Conductors are used insulated, without twists and branches.
With a single-phase network, the date of state verification of the meter is no older than 2 years, with a three-phase network - one year.

Place of installation of the meter in apartment buildings regulated by the project. The meter can be installed on the staircase or in the apartment - in. If placed in an apartment, it is usually not far from the door.

There are also several options in a private house. If the post is in the yard, you can place the meter on the post, but better indoors. If, according to the requirements of the power supply organization, it should be on the street, they put it on front side at home in a sealed box. Automata going to consumer groups ( various devices) are mounted in another box in the room. Also one of the requirements when installing electrical wiring in a private house: the wires must be visible visually.

In order to be able to carry out work on the electric meter, an input switch or automatic machine is installed in front of it. It is also sealed, and there is no way to put a seal on the device itself, as on a meter. It is necessary to provide for the possibility of a separate seal for this device - buy a small box and mount it inside apartment panel or put separately on the landing. When connecting a meter in a private house, the options are the same: in one box with a meter on the street (the entire box is sealed), in a separate box next to it.

Single-phase electric meter connection diagram

Meters for a 220 V network can be mechanical and electronic. They are also divided into one-rate and two-rate. Let's say right away that the connection of a meter of any type, including a two-tariff one, is carried out according to the same scheme. The whole difference is in the "filling", which is not available to the consumer.

If we get to the terminal plate of any single-phase meter, we see four contacts. The connection diagram is indicated on the back of the terminal block cover, and in the graphic image everything looks like in the photo below.

If you decipher the circuit, you get the following connection order:

The meter is connected with wires stripped by 1.7-2 cm. The specific figure is indicated in the accompanying document. If the wire is stranded, lugs are installed on its ends, which are selected in terms of thickness and rated current. They are pressed with pliers (can be clamped with pliers).

When connected, the bare conductor is inserted all the way into the socket, which is located under the contact pad. In this case, it is necessary to ensure that the insulation does not get under the clamp, and also that the cleaned wire does not stick out of the case. That is, the length of the stripped conductor must be exactly maintained.

The wire is fixed in old models with one screw, in new ones - with two. If there are two fastening screws, the farthest one is tightened first. Tug lightly on the wire to make sure it is secure, then tighten the second screw. After 10-15 minutes, the contact tightens: copper is a soft metal and is slightly crushed.

This is with regard to connecting wires to a single-phase meter. Now about the connection diagram. As already mentioned, an input machine is placed in front of the electric meter. Its rating is equal to the maximum load current, it is triggered when it is exceeded, excluding equipment damage. After that, they put an RCD, which is triggered when the insulation breaks down or if someone touched the current-carrying wires. The diagram is shown in the photo below.

The circuit for understanding is simple: from the input zero and the phase are fed to the input of the circuit breaker. From its output, they go to the counter, and, from the corresponding output terminals (2 and 4), go to the RCD, from the output of which the phase is fed to the load automatics, and zero (neutral) goes to the zero bus.

Please note that the input machine and the input RCD are two-pin (two wires come in) so that both circuits open - phase and zero (neutral). If you look at the diagram, you will see that the load machines are single-pole (only one wire goes to them), and the neutral is supplied directly from the bus.

Watch the meter connection in video format. The model is mechanical, but the process of connecting the wires itself is no different.

There are three phases in the 380 V network, and electricity meters of this type differ only in a large number of contacts. The inputs and outputs of each phase and neutral are arranged in pairs (see diagram). Phase A goes to the first contact, its output to the second, phase B - the input to the 3rd, the output to the 4th, etc.

The rules and order of work are the same, only more wires. First we clean, align, insert into the connector and tighten.

The connection diagram for a 3-phase meter with a consumption current of up to 100 A is practically the same: input automatic counter-RCD. The only difference is in the wiring of the phases to consumers: there are one- and three-phase branches.

To determine and control the amount of consumed electricity, you must perform competent connection counter. Consider the existing connection methods three-phase metering.

The proposed meter connection scheme will be determined by its type. Today there are several types of three-phase meters:

direct connection (meters 0.4 kV);
indirect connection (through measuring transformers);
semi-indirect inclusion.

1 Connection of a three-phase meter with direct connection - without

Devices of this type are connected directly to the electrical network, by analogy with single-phase meters. They are usually designed for low throughput power (current up to 100 A), the holes for the wires have a cross section of 25 mm2 (or even 16 mm2).

- input of phase A;
- to the load of phase A;
- input of phase B;
- to the load of phase B;
- input of phase C;
- to the load of phase C;
- entering zero;
- output zero to the load.

2. Connection of a three-phase semi-indirect meter

These devices are connected to the network through current transformers, which makes it possible to use them in networks with rather high powers (up to 60 kW). Using this method of accounting, to determine the flow rate, the difference in readings must be multiplied by the set transformation ratio.

There are several types of connection of semi-indirect meters.

1

The process of connecting wires is as follows:

contacts 3, 6, 9, 10 - close and connect to the neutral wire;
contacts I2 - close, connected to terminal 11;
1 - to I1 phase A;
4 - to I1 phase B;
7 - to I1 phase C;
2 - to L1 phase A;
5 - to L1 phase B;
8 - to L1 phase C.

Figure - Star connection diagram

2. Ten-wire meter switching circuit

10-wire circuit

This circuit is characterized by improved electrical safety, due to the isolation from each other of the current and voltage circuits.

3. Connection of a three-phase meter for indirect connection

These devices are designed for high-voltage connections (6-10 kV and more), the connection is realized using voltage and current transformers.

Below are the main connection diagrams through current and voltage transformers:

1) Scheme for connecting a three-element meter to a four-wire network with a grounded neutral: (Figure below)

2) Scheme for connecting a three-element meter to a four-wire network. Three current transformers, direct voltage connection:(picture below)

3) Connection diagram of a three-element meter to a three-wire line - two current transformers, three voltage transformers:(picture below)

When connecting a three-element meter according to scheme No. 3:

on phase B is calculated with the deduction of the zero sequence current;
currents of direct, negative and zero sequence of the fundamental frequency (symmetrical components) are not used;
active and reactive power in phase B are calculated with the deduction of the zero sequence current from the phase current;

4) Scheme for connecting a two-element meter to a three-wire line - two current transformers, two voltage transformers(picture below)

When connecting the meter according to schemes No. 4 and No. 5:

the zero sequence of the fundamental frequency (symmetrical components) is not measured;
currents of direct, negative and zero sequence of the fundamental frequency (symmetrical components) are not measured;
connection capacities are calculated by the formulas;
the accounting of electric energy is carried out taking into account the above remarks.

5) Wiring diagram of a two-element meter to a three-wire line - two current transformers, direct voltage connection (picture below)

Attention !: The ability to connect according to a specific scheme must be indicated in the passport or manual for a specific type of meter.

In houses, apartments, garages, as a rule, a single-phase power supply from 220 volts is provided. Each electric meter has a zero phase input and output. However, sometimes it becomes necessary to connect a three-phase meter when electrical devices consume power over 10 kW - various machines, electric welding, etc.

Benefits of three-phase power supply

There are many electrical household appliances that only operate on 380 V.
Excessive load on a single-phase input can serve as the basis for voltage surges for both your house or apartment, and for your neighbors. This, in turn, can reduce the lifespan of household appliances.
There is no need to install a cable or wire of large cross-section. Indeed, according to Ohm's law, with the same load of 380 volts, a large electrical power is supplied.
Provided that a three-phase and a single-phase electric motor will consume the same energy, the mechanical power of the latter will be significantly less.

Varieties

Three-phase electricity meter can be direct and indirect inclusion. In the latter case, the connection is made by means of a current transformer. Indirect inclusion is used to meter electricity at heavy loads. Direct inclusion is used in simple houses and garages, since in these rooms the load does not exceed 100 A, and the maximum power is no more than 60 kW.

The connection of a three-phase meter is carried out in a special electrical panel with a platform designed for fixing 3 screws.

Connection diagram

A cable with five conductors is inserted into the electrical panel, consisting of three phases, a grounding conductor and zero. The first contact is connected to phase "A", to the third contact - "B", to the fifth - "C".

From the counter from contacts 2, 4, and 6 phases go to the machines for electrical consumers. Zero approaches the seventh contact and exits the eighth. A ground wire is connected to the grounding bar of the electrical panel.

The old three-phase induction meter is connected according to a different scheme. A jumper is installed on contacts 1 and 2, the phase is connected to the first contact and from 3 contacts goes to the load. The same should be done with the rest of the phases, connected by jumpers on pins 4-5 and 7-8. A phase enters on pins 4 and 7 and exits from pins 6 and 9. Then the zeros are connected.

The new three-phase meter can be connected to the data transmission network to the control room. Connection to a low-current network is carried out through special contacts.

More detailed diagram The connections can be found in the technical data sheet supplied with the device or on the back of the contact cover.

Statement

To install a three-phase meter, you need to write an application to the company engaged in the supply of electricity. A qualified specialist should connect this meter. This is not only a requirement of organizations supplying electrical energy, but also the safety standard. An unprofessional installation of the meter will cost dearly not only the owner of the property, but also the master himself.

Place of installation

The three-phase meter is installed in the place where the electrical wiring runs. All wires passing through the apartment are connected to the input terminals. The output terminals act as an electrical flow separator.

It is necessary to install a metering device only in places easily accessible for maintenance, in special cabinets, on boards, panels, that is, on a rigid base. In accordance with current regulations, the meter panel must be installed at a height of at least 1.3 m and no more than 1.7 m.

Sealing

After the three-phase electricity meter is installed, it should be sealed. This procedure is performed by a specialist of the organization that supplies electricity. After sealing, you can proceed with the installation of electrical wiring.

Safety

If a three-phase meter (price on average from 2,900 rubles) is installed where there is a danger of contamination or in a place accessible to unauthorized persons, then it is preferable to install it in a special cabinet. This cabinet has a window at the dial level and is locked with a key.

The presence of rations and twists in the wiring to the meter is not allowed. The minimum cross-section of wires must be at least 2.5 mm 2, aluminum wires not less than 4 mm 2. During the installation process, it is necessary to leave the ends of the wires at least 120 mm near the metering devices. In rooms with a voltage of less than 380 Volts, it is necessary to provide for the disconnection of the device with a special switching device at a distance of 10 meters from the meter.

When installing the meter, it is important to ensure strong and reliable contact of the wires to be connected. The terminal screws should be tightened in 2 steps. When using a copper flexible wire, it is recommended to pre-tin with solder. It is advisable to use tin-lead solder, which will provide a more secure bond. After six months of operation, it is recommended to call a specialist from the supplying company to check the contacts in the terminal row.

Installation and operation

The inclusion of a three-phase meter must be carried out in accordance with the PUE (Electrical Installation Rules).
Operation is carried out taking into account the "Rules for the technical operation of electrical installations of consumers" TKP 181-2009.
It is necessary to turn on the metering device in accordance with its diagram and nominal data, which are located on inside clamping block.
Installation, disassembly, verification, repair, opening and branding should be carried out only by authorized organizations and persons, in accordance with the current regulatory documents and in compliance with the phase sequence.
A three-phase meter (price depends on the manufacturer) takes into account electrical energy in kW / h.
Transformation ratios that are not taken into account by the device are indicated on an additional shield fixed to the terminal block cover. In this case, the energy value on the primary winding of the transformer is determined by multiplying the reading of the device and the coefficient K.
The metering device window, in which tenths of kW / hour are indicated, is separated by a comma and bordered in black. In meters 10-40A and 50-100A there are no shares of kW / hour.
A three-phase "Mercury" meter or any other device should be mandatory once every 4 years, undergo state verification according to STB 8003-93.
Verification is carried out in accordance with GOST 8.259-2004.
The presence of readings on the meter is not evidence of its operation, it is just the result of the verification of the device at the factory.