For household electrical networks for 220 and 380 V, metering devices of induction or electronic type are used. In the process of replacing obsolete devices or installing new ones, the connection diagram of the electric meter is selected depending on the number of phases and the load power. Installation of the device is made with its mandatory registration and sealing.
Types and features of counters
An electric meter is a special device that allows you to record energy costs of direct or alternating current. It is intended for installation in an apartment or house. There are several types of appliances.
According to the principle of action
Manufacturers produce such modifications:
- Electromechanical. Induction electric meter operates on the principle of the formation of a magnetic field by two coils - current and voltage. The field provides rotation of the disk, and it activates the counting mechanism. As the current and voltage parameters increase, the disk spins faster. Warranty period of products is 15 years.
- Electronic. The device is compact, counts at several rates. The electronic device displays the readings on the display and stores them in memory. It can be connected to the smart home system.
The accuracy of induction models is 2.5. Electronic often fail.
By the number of tariffs
There are models:
- single tariff - keep records on one system;
- multi-tariff - calculate energy costs at the daily and night tariffs.
Devices with several tariffs are optimal for rooms with a large number of household appliances.
By way of fastening
Devices are installed on fixing bolts or Din rail.
The power of the device must be selected according to the power of all equipment.
Legality of self-connect
Connecting an apartment electricity meter without sealing it is classified by the legislation of the Russian Federation as unaccounted for consumption. It is understood as the absence of a contract with the provider, self-installation or shutdown of the device, failure to provide information on the amount of energy consumed. Sanctions are applied to the violator in the form of a fine of 4 thousand rubles. Base - Art. 7.19 Administrative Code.
According to paragraph 81 (8-9) and paragraph 81 (14) of Government Decision No. 354, citizens apply to the energy sales office to sign an agreement and install a control seal. Only after installing seals is it allowed to connect the meter.
Sealing is a free procedure.
Rules and requirements for the installation of the meter
Before you connect a counting device, you need to study the standards. The following connection conditions are spelled out in them:
- transferring the device on the basis of Government Decision No. 354 is carried out at the expense of the user, if this does not contradict the requirements of the EMP;
- the device is installed in hard cabinets, switchgear, on panels, walls, in niches;
- Settlement nodes are placed on the border of the operational responsibility of the consumer and the provider - the commissioning of an apartment, ASU, main switchboard;
- the screen of the accounting tool should be freely visible by the representatives of the supplier company;
- for a network with voltage up to 380 V, the rule applies - the distance of the electric meter to the switching devices is not more than 10 m;
- installation of the meter in the street is carried out in a sealed enclosure at a temperature of +5 degrees;
- The counter is set at a height of 0.8 to 1.7 m. The optimum height is 1.4 m.
The manufacturer's seal on a three-phase electric apparatus should not exceed 2 years, on a single-phase - 1 year.
The procedure for connecting the old meter
Outdated counting devices include single-phase models that count electricity at a common rate. They are installed in an apartment or a private house.
Scheme selection
The connection sequence for a single-phase energy meter is indicated in the passport, instructions or form from the manufacturer. You can find the circuit in the instruction manual or on the back of the terminal cover.
Work stages
The correctness of the action depends on the understanding of the scheme. In the center is a single-pole device, to which a power wire (zero and phase) is connected to the left. To the right are the load output cables. Through them, current flows to the lighting system, outlets, electrical appliances.
The terminals are connected to the wires as follows:
- terminal No. 1 - white / brown / black phase input cable;
- terminal No. 2 - white / black / brown input phase wire from which the apartment is powered;
- terminal No. 3 - neutral blue / blue-blue conductor of the input cable;
- terminal number 4 - blue / blue-blue zero load output cable.
Additional terminals are used to connect to service equipment.
Features of the connection diagram of a single-phase meter in the shield
For a home electrical network, the meter is connected in combination with protection devices. All nodes are in SchUR. To connect a single-phase electricity meter, you will need:
- Place a single-pole switch and insert a phase input cable into it.
- From a single-pole circuit breaker, output the phase to terminal No. 1 of the meter.
- Insert a working zero on terminal No. 3 and a protective zero on the neutral bus.
This scheme is recommended by the PUE and is suitable if an old accounting device is installed in the house.
Features of connecting three-phase meters
The three-phase meter circuit is implemented directly or indirectly. The first option is suitable for low-power consumers, the second - for equipment in a three-phase network.
Direct Connection Specifics
Connect the device in a direct way as follows:
- Stripping the cable from insulation and connecting it to a three-phase machine.
- Connection of three phase cables to the terminals No. 2, 4 and 6 of the meter.
- Conducting phase wires to terminals No. 1, 3, and 5.
- Supply of input (terminal No. 7) and output (terminal No. 8) neutral wire.
- Installation of 3-pole circuit breakers.
For a single connection of single-phase devices from the outgoing phase, neutral neutral wires are used. Several groups of single-phase consumers are fed evenly through switches of different phases.
Indirect connection
If the load exceeds the current rating, a special isolating device is used. The transformer is available with two windings. The first is a bus threaded through the middle, serves to protect the gap of power wires. The secondary winding in the form of turns of a thin cable is fed to the meter.
An indirect connection scheme for a three-phase electric meter is implemented by fixing transformers to the back of the cabinet. The primary windings are connected after the input switch and protection fuses into the gap of the phase cables. Connection is done like this:
- Supply of one end of the cable with a cross section of 1.5 mm2 per section from the A-phase power wire to the transformer.
- The output of the second end of the cable to the terminal number 2 of the counter.
- A similar connection of phase B and C wires, their output to terminals No. 5 and No. 8.
- Laying wires with a cross-section of 1.5 mm2 in the direction from the terminals of the secondary winding to terminals No. 2 and 3 of the electric meter.
- A similar connection of the windings of devices B and C to terminals No. 4, 6 and No. 7, 9.
- Connect terminal No. 10 to a common neutral earth bus.
Without phasing, the instrument will give incorrect readings.
Mounting Materials
An electric meter is connected after selecting a circuit and acquiring materials. To correctly and efficiently connect an apartment meter, you will need:
- auto switches taking into account the maximum current rating;
- insulation devices;
- tools with insulated handles;
- fasteners - screws and nuts;
- wires
- din rail.
Further work is carried out according to a strict algorithm.
Connection steps
Initially, you need to calculate how many phases in the home electrical network. Under them, the number of circuit breakers is selected. In the future, the device will connect as follows:
- Mounting the device in the shield with special clamps.
- Installation in a rack box on insulators with screws.
- Mounting of circuit breakers on a rail and fixing with a latch.
- Fixing the ground and protection tires to the rail or insulators in the shield so that there is a gap between them.
- Connecting the load to the switches.
- The connection of the machine with the counter.
- Load connection.
- Installation of connecting jumpers.
- Connecting the meter to consumers.
- Mounting the shield housing to the wall.
- Inspection of wires for proper connection.
Only after checking the cables can you turn on the power to a residential building or garage. At the last stage, the user contacts the power supply to test equipment and install seals.
Characteristics of some models of electric meters
When choosing a meter yourself, you need to consider how electricity will be consumed. Manufacturers produce models that can accurately keep track of energy costs:
- SRZU-I 70D. A pulse device that simultaneously transmits, collects and analyzes information. A measuring transformer is used to power the sensor. The receiving unit through the electrical circuit receives a signal of the LED about the energy consumption for a certain period of time. Data is displayed on the screen;
- Mercury 234 ARTM - RO PB. The three-phase multi-tariff model is designed for a network with a current of 5-10 A. It is installed on the street, as works without failures at a temperature from -40 to +70 degrees. The accuracy class of the device is 0.5;
- PSCH-4TM.0.5 MK. The multi-rate single-phase device operates at a current of 5-10 A. The accuracy of the readings is 0.5. Designed for operation in the temperature range from -40 to +60 degrees;
- CE 102M S7145-JV. It is calculated on 4 tariffs, has the 1st class of accuracy. The universal multi-tariff device is suitable for 220-230V networks with a current strength of 5 to 60 A.
The presented models are intended for apartments, houses and cottages, as allow you to plan energy costs and calculate a fee for them.
The self-connecting algorithm of the meter is based on its type and number of network phases. Before starting work, it is necessary to coordinate the installation, conclude a contract with the energy sales company. The device must be sealed.
