How to connect a single-phase electric meter: types of structures, a simple do-it-yourself installation scheme

Electricity metering devices are installed in every apartment and have been serving people for many years. Over time, they break down and require quick replacement. This work can be done independently or with the help of specialists. The first option is considered the most acceptable, since it allows you to reduce financial costs. In order to perform this procedure, you need to know how to connect a single-phase electricity meter.

Varieties of designs

Metering device manufacturers offer consumers two main types of meters. Both of them allow apartment owners to control their energy consumption and minimize their cash costs.

Induction meters

These devices are considered the most famous and commonly used. They gained their popularity due to the ease of installation, durability and accuracy of the readings. Before you connect a single-phase electric meter (induction) with your own hands, you need to study in detail the principle of its operation, advantages and disadvantages. All this information will help you choose the right model of the device, which is ideal for each specific apartment.

The principle of operation of induction devices:

1. The meter is equipped with two coils, one of which is current and the other is voltage. In the course of their operation, magnetic fluxes arise that penetrate through the aluminum disk. The result is the emergence of an electromechanical force that rotates this structural element.

2. This process causes rotations of the disc axle interacting with the counting mechanism (worm gear).
3. The received information is transmitted to digital drums, which allow taking meter readings at any time.
4. With an increase in power consumption, the disc rotates faster, and with a decrease, the brake magnet begins to act. Because of this, interaction with vortex flows occurs, which slow down the rotational speed of the disk.

Induction meters were very popular during the Soviet era, when no alternative devices were produced. At the beginning of the new century, such designs were gradually replaced by more modern and high-quality ones. Despite this, most families continue to use mechanical designs, which have several important advantages:

• high degree of reliability;
• durability;
• low cost;
• the ability to withstand sudden voltage drops in the network.

Despite the sufficient number of positive aspects, induction appliances have several disadvantages. They must be taken into account before purchasing a device and starting its installation. Otherwise, you may encounter various problems that will complicate the operation process and make it less convenient.

Disadvantages of mechanical meters:

• low accuracy;
• lack of protection against theft of electricity;
• at low loads, the reading error increases significantly;
• high current consumption by the device itself;
• large dimensions.

Electronic models

These devices are distinguished by their reliability and high accuracy. They gained their popularity due to the ability to work in a multi-tariff mode, which operates in some states. Thanks to this, losses and electricity costs are significantly reduced.

The principle of operation of electronic meters is simple and consists of the following stages:

1. An ordinary analog signal is supplied to the current sensors.
2. There it is converted into a digital code that is equal to the power used.
3. After that, the signal goes to a special microcontroller.
4. In it, it is deciphered, and the result is displayed on the display.

In addition to the standard function, electronic metering devices can perform several additional ones. They have a special chip built into them, which allows you to save data on electricity consumption for a long period of time. In addition, the device is equipped with an electronic clock and an optical port used for programming the device.

Electronic devices have significantly more advantages than mechanical ones. Among them are the following:

• the ability to conduct multi-tariff metering of electricity;
• ease of reading information;
• the ability to store information about the amount of electricity spent for a long time;
• high accuracy;
• the ability to control the power of the consumed energy;
• small size;
• the ability to record all attempts to steal electricity;
• remote data acquisition.

Even such a high-quality device has several disadvantages. They are much less than advantages, but it is not recommended to neglect them. Among them stand out:

• high cost of the device;
• sensitivity to sudden voltage drops;
• the complexity of repair and maintenance work.

Installation process

In order to connect a single-phase electricity meter and machines, it is necessary to complete the installation process correctly. In this case, it is important not only to follow the recommendations of the manufacturers, but also to listen to the advice of experienced electricians. Only in this case it is possible to achieve the desired result and complete the work in a minimum amount of time.

Selection of materials and tools

Before properly connecting the electric meter and machines, you need to prepare all the materials and tools that you will need in your work.

Professionals recommend that you do this work in advance, so as not to engage in a long search for this or that subject later.

For installation you will need:

1. New single-phase electricity meter. When buying it, you should pay attention to the presence of a seal and a stamp of passing technical control. In addition, it is necessary to choose models that can withstand the load in the mains.

2. DIN rail. It is used for mounting only those devices that have a special type of attachment. You can buy it in almost all specialized stores selling electrical equipment and components.
3. Protective box. If the master plans to install a meter indoors, then it will be enough to buy a standard product. In the case of installing the device on the street, it is necessary to choose structures made of moisture-resistant materials that can withstand temperature extremes. Any model of a protective box must provide openings for incoming and outgoing wires.
4. Circuit breakers or residual current devices. Professionals recommend using them to prevent injuries of varying severity. The required number is determined by calculations carried out in the design of the entire power supply system.
5. Special tires. They can be mounted on a DIN rail and serve as a distribution and switching function. In modern switchboards, these elements are included in the design in advance.
6. 
   Mono-core installation cable. In most cases, PV-1 copper wire is used.
7. Fasteners. Most often, plastic ties, dowels and self-tapping screws are used.
8. Insulating tape. It will be used not only for its intended purpose, but also for marking wires (phase, zero).
9. A hammer drill with a drill (the diameter should be equal to the dimensions of the dowels used).
10. Pliers and wire cutters.
11. Construction knife.
12. Insulation stripper.
13. A set of screwdrivers of different sizes.
14. Ruler, tape measure.
15. Building level.
16. Soldering iron with a set of all the necessary accessories.
17. Tester (indicator screwdriver) used to determine the presence of voltage in the network.
18. Compiled diagram for connecting an electric meter. This work can be done by hand or with the help of a highly qualified specialist. The first option is cheaper, but requires certain knowledge and skills in conducting such events.

Procedure

In order to connect a single-phase electric meter without any problems, it is necessary to observe precautions and precisely follow the drawn up diagram. This will help to quickly and efficiently install the device, as well as to avoid any injuries.

Installation sequence:

1. The room is de-energized and the absence of voltage is checked using an indicator screwdriver.

2. A section of the wall is marked for the box for the counter. It is recommended to choose a location so that it is convenient to take readings from the device.
3. A punch is taken, and holes are drilled with it in the places where the protective box is attached to the wall.
4. Dowels are inserted into them, and the structure is mounted. At the same time, it is important to use a building level that will help level the product in a horizontal plane.
5. At the next stage, a single-phase electric meter is installed, as well as additional equipment (buses, circuit breakers).
6. The DIN rails are cut to the desired size and installed in the chosen location.
7. After that, the supply wire and the load cable are laid. If the meter is mounted outdoors, then special rubber seals are used to protect the device from moisture ingress.
8. The insulating layer is removed from the edges of the wires. This work can be done using a special tool or an ordinary sharp knife.
9. A cable reserve is left in the protective box, which is necessary for repair work or re-installation. Experts advise using wires that will be 2 times longer than necessary. In addition, it is recommended to avoid kinks and sharp turns, which can damage the insulation layer.
10. Then the input cable is connected to the machine. In this case, it is checked which of the wires is phase, zero and ground. In most cases, they have a certain color of insulation.
11. The electricity is turned on and the presence of voltage is checked using an indicator screwdriver. In addition, you can check the indicators between all the wires, which should be approximately equal to the standard (220 V).

12. The room is again disconnected from the power supply and the cable is connected to the machine. To do this, a zero contact is connected to the upper right contact, and a phase contact to the left. Grounding is put into a special terminal, which was previously installed in the shield.

13. The contacts are securely tightened with a screwdriver and left for a quarter of an hour.
14. Retightening is carried out after the specified period of time. This must be done in order to exclude the possibility of loosening of the contact, which can occur due to the compression of the wires.
15. The zero and the phase coming from the output of the machine are connected to a single-phase meter.
16. Small jumpers are made and used to switch equipment. For this, a wire of the right size is taken and with the help of pliers it is given the desired shape. Then the ends are stripped and fastened in the terminal.
17. The rest of the jumpers are made in the same way. Moreover, each of them is marked with multi-colored electrical tape.
18. At the very end, the load cable is connected to the machines.
19. All wire attachment points are carefully checked.
20. The voltage is switched on, the device is checked for operability.

The installed single-phase electricity meter must be sealed. For this, a corresponding application is made to the power supply organization and an act is drawn up. Then the time of the visit of their representative is appointed and permission to use the new device is issued.

Connecting a single-phase electric meter is a rather difficult undertaking that requires a large investment of time and money from the master. With proper installation and following all the recommendations of professionals, you can speed up the installation process and avoid any problems.