An electricity meter requires replacements infrequently. Previously, this was not done until the complete failure of such a device. Now recommend replacing such equipment that has served its life specified by the manufacturer. Most firms put a life of at least 16 years on electricity meters. If you do not have an idea about which element to choose, then before buying you need to familiarize yourself with the main characteristics and features of each type. Electricity meters are divided into two large types: induction and electronic.
Induction
This type is also called mechanical. It includes: a coil for voltage, a disk of metal, a coil for current. Magnetic voltage is generated between the two coils, resulting in a rotation of the metal disk, which drives the numbers showing the energy expended.
The advantages of such a counter can be considered low cost and high service life. 
But there is a drawback, too, the readings of electricity meters of this type amount to an error of up to 2%. Such elements have existed for quite some time, and even with a large margin of error, demand for them is still great.
Electronic
This type of meter is fully electronic, even there are no signs of mechanics. Current flows directly to semiconductors and microcircuits. The display on the counter indicates that the microcircuit is reading. Such a device has a very small error, so its accuracy is a big plus. It also has a small size. Of the minuses - a relatively short service life and high price.
There are electricity meters by the type of connection:
- the first type is connected directly to the power circuit;
- the second type is connected first to the transformer through special power circuits.
Counters can vary by network type.
Single phase
Installation of electricity metering devices having one phase is advisable where the energy consumed does not exceed a threshold of 10 kV. 
You can connect such a meter to a single-phase two-wire network. The single-phase device is suitable for installation in a house or apartment.
Three phase
The operation of electricity meters of this kind will be advisable in places where the costs are high, for example, in factories or in apartment buildings. For the convenience of counting and saving, you can set the counter depending on the tariff (for example, single tariff). Almost everyone has such a device. It is suitable only to calculate the energy consumption according to its indicators for the current time. In this case, the tariff will be the same.
Two-tariff is already more functional and can allow calculating the energy consumption for two different periods. For example, for daily use one price, at night - another. Multi tariff. This counter provides a calculation function for several tariffs at once, which can significantly save money.
To determine the phase, you can just look at the markings of the old. If the parameters 220/230 V are indicated there, you need to choose a single-phase. If 230 / 400V is specified - multiphase.
You can choose a device according to the load as follows: you need to know the usual load in the house, for example, its size is 60A and the power is 15 kW, you should take into account small fluctuations, and choose a meter with a higher load, for example, 100 A. All electricity meters have such data on their markings.
The choice of tariff depends on whether it is profitable.
It is necessary to make a simple calculation, but before buying a multi-tariff meter it is important to go to the company that provides these services and find out if installation is possible. If not, then the purchase of a device with several tariffs will disappear by itself.
Decide on the mounting option also before purchase. You can install the counter indoors, you can outside. Fasten it to a bolt or adapter beam.
Whether or not to purchase a device with additional functions is up to the consumer to decide. Innovations such as backlight or display will not affect the quality of the element itself, so their need is not determined by anything. Anyone can buy a device with a modern design.
Checks before sale are subject to all metering devices, without exception. Testing takes place at the state level, the accuracy and operability of the device are subject to measurement. When the check is passed, a mark is put in the product passport, and a seal of the manufacturer is installed on the element itself. Periodically, checks are necessary, and their terms are regulated by the instrument passport.
The accuracy class plays an important role, it shows with what error the counter will work. For a residential building, this indicator can be within 2%.
Installation and reinstallation
When connecting a new electric meter or replacing it, it must be registered again. To do this, it will be necessary to invite representatives of the company engaged in electricity sales. Workers will check the correct connection and, if they do not detect violations, will issue a permit for the operation of the device and put a seal on it. After it was possible to correctly install the metering device for electricity, it is necessary to take the initial readings. The new element must appear in the State Register and have a certificate of conformity.
Common house
After the reform of the housing and communal services in all houses, the installation of a common house electricity meter is mandatory. 
Now, the calculation includes the costs of common needs. This is lighting the entrances, basement, energy for the pump and so on.
Replacement
Who should change the electric meter located in the entrance, if it is assigned to a certain apartment? When it is located in the apartment, there is no doubt - the owner should do it. Why, then, should the management organization be removed from the apartment? This is the same individual meter for electricity for a particular owner. Thus, to replace the device, taking into account the current consumption in the room, must be its owner. But he can be lucky if the ZHEK arranges a planned replacement of all electricity meters.
Mandatory installation applies to water and electricity meters. 
By law, such devices must be installed in each apartment, even fines for non-compliance with this rule are provided. Also, representatives of the management company can forcibly install these accounting devices.
Installation steps
To correctly install electricity meters, you need to have sufficient knowledge and experience. If this is not available, it is better to entrust such a process to specialists.
Independent connection of the meter is possible if you familiarize yourself with the elementary connection diagram. Installation rules are best followed:
- The first step is to study the technical description of the device, it contains a connection diagram. It can still be found on the inside of the device cover.
- Then follows the installation of the meter in a specially designated place - a box or a shield that should be well fixed. Next, you need to put in the shield a previously de-energized cable and a wire extending from the internal wiring.
- The next step is to connect the wires exactly as indicated in the marking.
- After installation, you need to call a specialist from the company, who will verify the installation and leave a seal.
Water metering
A meter for the consumption of water is needed to measure the volume of water that passes over a certain period of time. The unit of measurement of such a counter is m3. We need such control of water consumption, first of all, to the consumer himself, he will pay only for what he really used. Water meters can be divided at the installation site: for cold or hot water. They differ in the material of the parts.
Calibration of the electric meter
Only a dedicated circle of people was familiar with such a term until recently; at present, it is known to both directors of large firms and ordinary consumers.
Energy prices are growing inexorably, so there is a need to control their consumption at the state level. In this regard, a number of laws were envisaged that stipulate the mandatory installation of new generation devices and their verification in accordance with the passport.
Each type of meter has its own set interval, during the period of which the readings of the device are recognized as true. If we talk about mechanical induction, then this interval is up to eight years. 
But the electronic counter of the latest models gives a guarantee of the accuracy of their readings for up to 16 years.
In this case, the replacement of electricity meters should be made by their owner and at his expense. The term must first be agreed with the inspecting authority. If there is a suspicion of a malfunction of the device, a check can be made ahead of time. But before calling a specialist from a similar authority, you need to make sure of the following:
- whether the wiring system is in good working order;
- Are there any receipts for payment?
You should also call an employee who agrees to remove the device and transfer it for inspection.
Check out of turn
You can verify the device out of turn in the following cases:
- lost certificate of verification;
- an unauthorized setup of the device was committed;
- when replacing old equipment with new.
The new law simply obliged many citizens of the country to replace the metering devices with new ones, since the first simply did not pass the test with modern measuring instruments. 
At the same time, the check passed according to several parameters. I had to replace such devices:
- in which the disk rotated unevenly, or its rotation was completely stopped;
- devices for which the indicator or display was faulty;
- devices with damage in the case;
- devices that do not have a seal of the State Register.
The purchase of an electricity meter should be done in specialized stores. So you can be sure of its safety and compliance with standards. In addition, such stores usually provide warranty services for the installation of devices.
So, we figured out the device counters and how to install them.
