How to connect a single-phase meter

As soon as electric power became widely used by mankind, special devices for and its - counters were immediately invented. These useful devices began to be used by the still in the in the 19th century and now any connection to electricity is simply unthinkable without the of the meter, and unauthorized electricity sampling is an serious offense. Naturally , there are rules of installation and operation of counters , regulated by the Rules of Electrical Installation Device( PUE), and the devices themselves are subject to strict accounting for and control over unauthorized access to them. Information on how to correctly connect an electricity meter single-phase, for sure, will be useful to anyone who does repairs in an apartment or engaged in building a house.

In most cases, installs and connects an electric meter, but in some cases it can be done on its own, entrusting the controlling bodies only to verify the correct connection and sealing. This article will describe how to properly connect

counter , which tools , components and materials will be needed for this, as well as what should be paid special attention.

Types of single-phase counters

Selecting counter for self installation and connection need, above all, make sure that the selected model is allowed to operate u and s an necessary documents. It is best to purchase counter in the power supply organization that will monitor, verify and service it in the future. But for the right choice, it is necessary to find out which electric meters exist.

How electricity meters can be connected

single-phase electricity meters can have different types of connection:

• Direct connection when counter is connected directly to the power circuit. Almost all single-phase counters are included in this way.
• Transformer connection, when the counter is connected via special transformers . These meters are used mainly in the industry for accounting for in electrical networks with very high load.

Types of

meter designs meters can be of different design:

• induction or electromechanical meters, which are well known to us on a disk that rotates faster the more the current flows, and means , and power consumption. The di is driven by the magnetic field of the voltage and current coils, which are connected respectively in parallel and in series with the measured load. The special mechanism counts the number of revolutions, by which one can judge the of the consumed power. Such counters have a low accuracy class( 1.5 and higher), so they are gradually inferior to more modern models.

• Electronic counters , which are replaced by induction. They have high accuracy class( 0,5-2,0), more are reliable and compact in size. Measurement in them occurs a special electronic circuit, which generates pulses in proportion to the load: the higher it is, the higher the pulse repetition frequency will be. By the number of pulses, one can judge of the consumed power.

A very important advantage of electronic meters is the multi-rate capability, which allows the inclusion of powerful consumers of energy( washing machines and dishwashers, water heaters) during the reduced tariff and thus save means .In addition, in some models there is the possibility of remote reading of readings and programming through various interfaces: infrared, RS-485, GSM, CAN and others.

If you plan to install the meter in the street, it is better to choose an electronic counter , equipped with an electromechanical reading device. At low temperatures, liquid crystal displays stop displaying information, although the counter regularly counts the consumed by the kilowatt-hours.

Required components and tools for setting the meter

In order to install the single-phase electric meter the following components will be needed:

• The itself is an electric meter .When purchasing the device, it is necessary to make sure that the is stamped, as well as the seals on the body of the counter. The terminal cover is sealed after connection. The model of the meter must correspond to the load described in the technical specifications - TU , they can be easily recognized in the power supply organization.
• If the counter of the is installed in an existing electrical panel or box, make sure that the fasteners are suitable for installation. Usually meters are attached to the of three screws. If the counter has a DIN rail mount, and there is no in the board, then the of its can be easily purchased from the store and installed.
• If counter will be installed in a new box, then you should purchase it. When installing outdoors, you need to purchase the side with for a degree of protection of at least IP54 , which has valve seals and special glands for incoming and outgoing cables.

Video: Street switchboard for electric meter

• Together with the , the power meter usually installs modular equipment to protect electrical wiring and people: circuit breakers, and in some cases also residual current devices - RCD .Their required number and denominations are calculated in the design of the power supply system, which is performed by specialists. Buy such equipment better than the well-known brands and only in specialized stores. According to the SAE to the of the , it is necessary to install the two-pole circuit breaker, which allows the maintenance of the of the meter, and also protects against short circuits and overloads. The switch rating must correspond to the allocated power and must be specified in the connection specification.
• For the distribution and switching of zero( N) and protective zero( PE) in electrical panels, special buses are used, mounted both on DIN-rail and in special fastening points. When buying them, it is worth considering that the zero bus is used with a blue plastic holder, and the protective ground bus is yellow or green colors. Some switchboards already have these tires by default.

• To connect all components of the electrical board, a mounting wire is required. To do this, use solid copper wire of the brand PV -1.The use of stranded wires is not recommended, and if they are used as input and output cables, the ends must be clipped and crimped with special tips of the appropriate diameter or to treat with a soldering iron.
• For fastening the switchboard or box to the building structure, and also for mounting the of the meter of DIN rails and busbars inside the electrical board, kit of fasteners is required: self-tapping screws, dowels, plastic ties.
• If the incoming and outgoing cables most often have a color-coded insulation, then the - mounting wire does not have its .Therefore, for marking phase and neutral wires, you need to have an insulating tape or heat shrinkable tubes of blue and red colors.

To install the single-phase meter you will need the following tools:

• Rotary hammer with drill corresponding to the plugs of diameter - for hanging the electrical panel or the box on the building structure.
  Pliers. Well, if there are several, with different sizes of sponges.
• Pliers.
• Knife for construction.
• Remover insulation.

• Tape measure.
• Ruler.
• Construction level.
• Screwdriver Set .
• Indicator screwdriver - for monitoring the presence of voltage.

• Soldering iron. It can be used for maintenance of stranded wire.

How to connect the single-phase meter

Before starting work on the installation of the new of the , make sure that the supply line is de-energized. Check for the presence or absence of voltage either by using the screwdriver-indicator , or by a multimeter. meter installation includes a number of simple technological operations .

• After checking the absence of voltage, the layout of the future installation of the flap or box for of the counter is made. The optimum height of the installation of the meter is 1.6-1.7 meters from the surface. This is the most convenient height for reading the meter of the meter and for carrying out any work.
• With a perforator holes in the construction structure are drilled in the planned places, dowels are inserted and the kc is mounted for and of the counter. It is necessary to control the level of the installation with a level.
• If the counter of the is mounted in place of the old, then after disconnecting all wires, the old counter is dismounted.
• According to the scheme, which can have many options, is installed and modular equipment( circuit breakers, RCDs, buses).If necessary, DIN-rails are installed, which can be previously cut off with a hacksaw to the desired size. The modular equipment is mounted using special locks or spring latches .Introducing the two-pole circuit breaker is better to mount in a special mini-box, which is then sealed by the power supply organization. This eliminates the possibility of connecting the load to the counter of the .

• is made input cables: power and load( apartment or house).If the box is installed on the street, then special glands are used: threaded or rubber - which seal the cable entry into the box, not permitting penetration of atmospheric moisture. To do this, the rubber gaskets are cut with a knife, and the threaded ones are tightened after the cable is passed through them.

• packing. The ends of the cables are made using a knife or a special tool. At the same time, care must be taken to prevent damage to the insulation of the wires when cutting the cable sheath. The cable entry through the stuffing box must be in the shell, the is still left with the 2-3 cm, and the remaining length is cut.

• The supply of cables is left in the shield: of the input and loads in order to be able to re-install. Usually the length of the cable is made twice as much as is necessary. At the same time, sharp turns must be avoided, which can lead to a break in the cable in the future.
• Before connecting the input cable to the two-pole machine, the conductors are checked for phase, working zero and protective zero ( ground).Usually the phase wire has a brown or red insulation color, zero working blue, and grounding the combined yellow-green .But there are cases when the color of the insulation may differ( see the figure).For a full guarantee, stripper is stripped with a wire insulation of 10 mm, spread them to a safe distance, briefly turns on the voltage and check the with a screwdriver with a phase wire indicator. Then the voltage between the phase conductor, the working and protective zero is checked by a multimeter. It should be 220-230 in the . After the this voltage is turned off.

• The input cable is connected to the input device. The phase conductor is connected to the upper left contact, and the zero wire to the right. The ground wire is immediately wound onto the corresponding terminal, which was mounted in the shield in advance. After that, the contacts are tightened with the screwdriver .After a few minutes, re-tighten, since the conductor under pressure of the terminal slightly is compressed by .Aluminum wires have an unpleasant property of contracting in terminals with time. Electricians say this: "The wires are running."That's why it's best to always use copper wires and cables, and periodically pull aluminum.
• From the output of the bipolar of the circuit breaker, the phase and working zero is connected to the by the electric power meter. All single-phase meters are connected by four terminals, where is their intended use for counter in in of all models:
  • o Terminal # 1 - for phase cable input.
  • o Terminal No. 2 is the phase output.
  • o Terminal # 3 is the operating zero input.
  • o Terminal No. 4 is the working zero output.

• For switching all modular equipment it is necessary to make jumpers from the wire PV-1.For this purpose, the distance from one terminal to the other is measured, the wire at a right angle is bent by pliers the required number of times so that the wire freely and without voltage approaches the terminal. The insulation is only stripped to a distance that allows the to reliably secure the to the terminal in the modular equipment terminal. For circuit breakers, RCDs and of terminals, the insulation is stripped to 10 mm, and for , the is 27 mm. If a number of circuit breakers are installed in the switchboard and the phase must be distributed, then make a jumper from the PV-1 wire without breaks or use a special comb , cutting off the desired size with a hacksaw.

• comb. The jumpers must be marked with colored insulating tape or heat shrinkable tubing. The phase wire is red and the neutral wire is blue. The wire is inserted into the terminal only of the bare part, the insulation is not allowed to penetrate. At the same time, bare parts of the wire should not look out of the modular equipment and the of the counter. Tightening of the m m of the modular equipment produces in two reception with a break of several minutes.
• In modern counters , each terminal has two screws. After the wire is wound in the terminal, tighten the upper screw. Then check the reliability of the tightening by pulling the wire. Only then tighten the lower screw. After a few minutes, the is pulled up by the again.

Video: Single-phase electricity meter connection

• The last connection is to connect the load cables to circuit breakers, as well as to the ground and ground bus. After this you should carefully check the correct assembly, tightening the terminals. It's better if the specialist does it. If everything is installed correctly, you can invite the representative of the power supply organization, who will also check the correct installation, seal the input circuit breaker and counter .An appropriate certificate is drawn up, after which it is possible to turn on the voltage and use the new electric meter .

Results of

• Installation of meter is best entrusted to a qualified technician who has the appropriate approval of .
• All operations of according to must be performed only when the voltage is removed.
• For the control panel, only the well-known brands of modular equipment should be used. The ratings of circuit breakers and RCDs must be selected only by a specialist.

Video: How to mount a counter, one of the options