Which electricity meter to put in a house and apartment: a brief overview of the types and a checklist of choice

Electricity consumption in everyday life is increasing every year, because the number of powerful household appliances in homes is not decreasing, but only growing. So that monthly payments do not hit your pocket too hard, you need to know exactly which electricity meter is better to choose for an apartment or for a house. Let’s figure out how to do it right.

All about choosing an electric energy meter

When to change it
Criterias of choice
Short checklist of your choice

When to change the meter

Replacing a metering device is a troublesome and rather costly undertaking. The owner needs to purchase equipment, pay for installation and sealing services. It is clear that without the need to do this there is no desire.

Reasons for replacement:

• Breakdown of the electricity meter.
• End of verification period.

In the latter case, it is possible to extend the use of the equipment, but it will have to be dismantled and sent for re-verification. After receiving confirmation that the flowmeter is working normally, it is put in place and sealed. Substitutions are made for other reasons as well. For example, if the owner of an apartment wants to switch to differentiated electricity metering. Then you have to install a multi-tariff device.

How to choose an electricity meter according to important criteria

A large number of varieties of electricity metering equipment are produced. We have identified seven criteria that will help determine which electricity meter to install.

1. Equipment type

For electricity metering, two types of devices with different operating principles are used.

induction

The design includes two coils. First, voltage is applied to the parallel winding, then to the current winding. As a result, vortex electromagnetic flows arise that rotate the disk. By means of a worm gear, this rotation is transmitted to the drum of the counting mechanism. Induction devices are durable. The declared service life is 15 years, but in reality it can be much longer. Their price is low.

The disadvantage is the high measurement error. For this reason, older models should not be used. New varieties, designed to meet modern requirements for error, can be installed in any houses and apartments. Induction units can only be single-tariff.

Electronic

The housing contains voltage and current sensors that transmit their signals to the converter. It reads them and redirects them to the microcontroller. This block decrypts the received information and transfers it to the counting device. The latter can be of two types: electronic or electronic-mechanical. In the first case, the readings are displayed on the display, in the second, a mechanical type circuit operates, similar to that used in induction analogues.

The advantage of electronic devices is the high accuracy of measurements. In addition, they can calculate energy consumption at different rates. There is a possibility of remote transmission of readings. The verification period for such meters is longer than for induction meters. The disadvantage is the high price and shorter service life.

2. Ability to use multiple tariffs

Electronic equipment is capable of operating in multi-tariff mode. This means that electricity consumption is calculated at user-defined intervals. What is needed if the region has different tariff rates for night and daytime. Some models are able to “cover” up to eight tariffs, but two-tariff systems remain in demand. All multi-tariff devices are more expensive than their single-tariff counterparts. Therefore, before you buy it, you need to determine whether it will be profitable. Make it simple. It is necessary to calculate the average energy consumption per month and the amount that will have to be paid at one tariff. Then break the expense into day and night, calculate the estimated fee. If the difference is about half of the usual payment, it makes sense to change the equipment.

3. Number of phases

There are two types of equipment.

• Single-phase. Designed to work with a 220 V network. It is these lines that are laid in apartments, all household electrical appliances are designed for them. Single-phase devices are recommended for installation in multi-apartment buildings. A three-phase device can theoretically be operated on such a line. But in practice, power supply companies refuse to register them.
• Three-phase. Designed for operation on a 380 V line. Water heaters, heating boilers, electric motors operate from such networks. A three-phase recorder is installed in homes where there are electrical appliances operating at 380 V.

4. Accuracy classification

It is indicated in the technical documentation and on the front side of the case. The value indicates the error that occurs in the measurements. It is recommended to use devices of accuracy class 2.0 or lower. Induction devices that served for a dozen years, or even more, had a class of 2.5. Therefore, all of them are subject to mandatory replacement, without waiting for the expiration of the verification or expiration date.

You need to know that the higher the accuracy of the measurements, the greater the amount in the accounts of consumers. Devices with a minimum error «notice» the very slight load. For example, they consider the minimum power consumption of equipment in the «sleep» mode. Therefore, it is recommended to choose devices with an accuracy class of 2.0.

5. Current load

The recorders are designed for different current loads. It depends on its actual performance which one to install the electricity meter. This can be determined in three ways.

• Calculate the load on the laid lines. This can be done by an electrician who has information on the number of lines and the size of the cable cross section.
• Take information in the Criminal Code or in the Housing Office about the number of amperes on the input line connected to the meter.
• Calculate the total power of the electrical appliances used.

The last option is the easiest. The owner will need to add up the rated power of all home appliances. Add a certain amount of kW “in reserve” to the resulting number, so that when buying new units you do not have to change the electric meter. A result within 10 kW indicates that it is possible to set the meter to 60 A, if the total power is greater, they take a device of 80-100 A.

6. Operating conditions

Recorders are designed to operate in different temperature ranges. So, they produce devices for working in heated buildings. At temperatures below zero, they are inoperable. They are recommended to those who are looking for which electricity meter is better to put in an apartment. Temperature insensitive models are available. They are allowed to be installed in unheated rooms or on the street. Devices are placed in summer cottages, in private houses. Do not operate the flowmeter in unsuitable conditions.

7. Mounting method

All manufacturers produce registrars with two mounting options:

• under the bolts. Fixes the device as securely as possible, prevents possible loss of contact and small shifts. Most often used for fixing on street shields. Installed with three bolts.
• On a DIN rail. It is mounted on a rail fixture in the electrical panel, so there is a groove with a latch-latch on the back of the case. Installing or removing equipment is easy, it is put on the rail with a groove.

Most manufacturers produce registrars with similar performance characteristics with different fixation options.

Checklist for choosing a meter

To choose the right registrar, we offer a small checklist. He will tell you what to focus on.

• Registrar type. For your home or apartment, they often choose electronic, for the street or giving induction. Select the required specifications.
• Release date. Electrical equipment is tested at the factory. Its date and results are recorded in the data sheet. A seal is placed on the body, its integrity must be checked. From the date of the first verification, the period until the next one is calculated.
• Intertest interval. Specified according to the technical documentation. If it is small, it makes sense to choose another model. A new single-phase recorder must be installed no later than 2 years from the date of the first verification, a three-phase recorder — one year. If this is not the case, a scheduled verification is carried out at the expense of the user who bought the “overdue” device.
• Completeness. The box must contain technical documentation marked with factory control. The registrar must be certified and approved for installation and operation in Russia. The integrity of the case and the seal is checked.

We figured out which electricity meter to install in a house or apartment. The correct choice depends on individual operating conditions. There are a lot of manufacturers producing accounting equipment. This is the case when domestic products are not inferior to imported ones. The Russian brands «Mercury», «Electromera», «Neva» have proven themselves well. In the line of models there are the simplest measuring devices, there are complex ones with many additional functions.