Do-it-yourself installation of an electric meter is not particularly technologically difficult and can be done by anyone. However, since the connection of metering devices is an extremely responsible operation, it is necessary to strictly follow a certain algorithm of actions. In addition, to ensure the legality of such an event, it is necessary to contact the office of the electricity supplier company, where you can draw up an agreement and obtain the necessary permits.
general information
As a rule, the meter is the property of the organization supplying electricity and, accordingly, the installation of these devices is carried out by the company's specialists. The consumer is solely responsible for the correct operation of the electrical equipment and for the safety of the protective seals. Thus, installing a meter with your own hands is only advisable if it is necessary to replace a faulty device, as well as when completely replacing electrical wiring or putting new facilities into operation.
The size of electricity bills directly depends on the correct operation of the electric meter, so it is necessary to monitor its serviceability from time to time. A large number of articles have been written about how to check an electric meter. You can independently monitor its functioning using one of the following methods:
- Checking the correct connection.
- Self-propelled test by unloading.
- Calculation of measurement error.
As for the location of the meter in an apartment building, there are special switchboards for these purposes. At the request of the homeowner, the electricity meter can also be placed directly in the apartment, but for this you will have to equip a special switch box.
In private houses, counters are located, as a rule, in vestibules or utility rooms. Recently, electricity suppliers have required the placement of metering devices in such a way as to ensure that inspectors can easily take readings from them without having to enter the territory of home ownership. On the other hand, such measures are designed to limit the ability of unscrupulous users to perform illegal manipulations with the meter, which are aimed at reducing the amount of electricity it takes into account.
It is not recommended to install an electric meter in rooms where the temperature drops below 0 degrees.
Types of electricity meters
To date, these devices are distinguished primarily by the principle of operation. There are the following types of electricity meters:
- Induction. The operation of such devices is based on the principle of electromagnetic induction. Meters of this type were extremely common in the last decades of the 20th century due to their high reliability, small measurement errors, and low cost. Currently, induction devices no longer meet the increasing requirements for electricity metering, for example, they are unable to work efficiently when the case is tilted more than 10, they are sensitive to temperature extremes and the effects of strong magnetic fields. In addition, today there are a fairly large number of ways to slow down or stop the rotation of the aluminum disk, which is included in the design of such devices. For this, a variety of devices are used - from special transformers to powerful neodymium magnets.
- Electronic electricity meters. Currently, such electricity meters are actively replacing outdated induction models.To a large extent, the state contributes to this by obliging consumers to install meters of this type, as well as increasing the requirements for the accuracy of electricity metering. The main advantages of electronic devices include their high reliability, measurement accuracy, small overall dimensions, the ability to account for electricity at several rates depending on the time of day, as well as significant difficulties that arise when trying to "deceive" such a meter.
Depending on the number of phases of the electrical network in which the electric meter is installed, a single-phase or three-phase model can be used. Single-phase devices are cheaper and easier to install and operate. In the vast majority of apartments in modern houses, it is a single-phase network that is used.
Currently used electricity meters should be accurate to 2 or 2.5%. According to GOST 6570-96 adopted in 1996 “Induction active and reactive energy meters. General technical conditions”, the accuracy class of devices serving household consumers should not be lower than 2.
There are meters designed to account for active and reactive electrical energy. Since in the power supply systems of apartments and private houses, where it is possible to independently connect electricity meters, active energy meters should be used, it makes sense to confine ourselves to considering only such models of them.
As for two-tariff or three-tariff devices, their installation is associated with obtaining additional permits from the electricity supplier and requires the conclusion of a separate contract. Recently, the load on electrical networks has increased significantly, which provokes electricity suppliers to encourage the population to switch to two-tariff (two-zone) metering devices.
The use of two-tariff meters makes sense only in case of significant electricity consumption during hours that does not correspond to the peak load on the electrical network. In addition to the high cost of the two-tariff (two-zone) meter itself, additional funds will have to be spent on its programming.
As a rule, three-tariff devices are used in enterprises, although their installation in private apartments is not prohibited by law.
Another feature by which electricity meters can be classified is their voltage and rated current. Installation of devices that are designed to operate with a rated current exceeding 100 A is carried out by indirect connection (through current transformers). Such devices are used in three-phase networks with powerful consumers, their installation is carried out exclusively by specialists.
When choosing a meter model for do-it-yourself installation, you need to pay special attention to the time of sealing the device case. According to existing laws, the seal on a single-phase meter should not be older than one year.
Counter installation
Before installing an electric energy meter with your own hands, you should determine the place of its installation and prepare the necessary tools and materials. Electrical stores have a large selection of shields used to install these devices. Both complete sets and their individual elements are offered. Meters installed on a finished base, single-phase or three-phase, are very popular.
The choice of the required model of the meter and the protective shield is carried out based on the features of the connection and the place of installation.
Tools and materials needed to install a single-phase meter with your own hands:
- Electrical energy counter.
- Protective shield.
- Unipolar low voltage indicator.
- Tools with dielectric handles (pliers and screwdrivers).
- Nuts, bolts and screws.
- Terminal block.
- DIN rail.
- Automatic switches and UZO.
The electric meter must be mounted vertically on the wall. As a mounting point for this device, a metal or wooden sheet, as well as a special protected box, can be used. The installation height of the counter is not strictly regulated, however, there is a ban on placing them outside the zone of free visual control. The most convenient in practical terms is the installation of counters at the height of the eyes of an adult (up to 1700 cm).
Before starting work on installing an electric meter with your own hands, you should carefully study the general wiring diagram of the apartment. This will make it possible to correctly assess the number and power of consumer groups and, accordingly, the number and type of devices used in the connection scheme. circuit breakers and RCD.
As an example of connecting a single-phase electric meter, the following diagram can be considered:
When carrying out work on installing the meter with your own hands, you should adhere to the following algorithm of actions:
- A DIN rail is mounted in the electrical panel using screws, to which all electrical equipment will be attached.
- With the help of special fasteners or DIN rails, the meter is mounted to the shield body.
- In specially designed places inside the shield, terminal blocks are installed for connecting zero working and ground wires.
- Automatic switches are being installed according to the number of consumer groups.
- Installation of a residual current device.
- The wires leading to the load are connected to the lower clamps of the circuit breakers. The top clamps of the machines must be interconnected using jumpers, which can be made by hand or purchased at an electrical store.
- The electricity meter is connected to the load, for this its second contact is connected to the phase, and the fourth to the neutral wire.
- To connect the meter to the network, it is necessary to connect its first contact to the incoming phase wire, and the third to the corresponding neutral conductor.
To facilitate the further operation of the devices that make up the electrical panel, it is necessary to draw up a diagram indicating consumers (sockets, light switches, washing machine, electric stove, etc.) and also mark the wires connected to the meter and switches with appropriate marking on the diagram.
Features of connecting a three-phase meter
Connecting a three-phase do-it-yourself electricity meter can be well illustrated using the following direct connection diagram:
As can be seen from the figure, the basic principle of connecting this device to the electrical network remains the same. The presented scheme is far from the only one by which a three-phase meter can be turned on. Since these devices are often used for electricity metering in networks with powerful loads, various indirect connection schemes in a three or four-wire network can be used to install them. In this case, additional current or voltage transformers are used.
Another important point that must be taken into account when installing a three-phase meter with your own hands is the observance of the order of phase sequence. If a simple replacement of one device with another is carried out, then you need to connect the wires to the terminals of the new device in the same order as they were connected to the old one. If a new meter is installed, the correct phase sequence should be determined using a phase indicator.
You should separately dwell on the installation of a circuit breaker in front of the meter. From the point of view of the safety of the electrical wiring of the apartment, as well as the maintenance and replacement of the meter, such a switch is necessary. However, unauthorized installation of this device may lead to well-founded claims from the controlling organization. In order to avoid conflict situations, the circuit breaker must be enclosed in a special case, which is sealed by a representative of the electricity supplier.
Thus, the possibility of using the machine to turn on or off the electrical network is achieved, and at the same time, the possibility of interfering with its design in the area located before the electricity meter is limited.
