counter records the amount of electricity consumed - it is not so useful as a necessary tool.Residential and industrial premises, not fitted with this unit, but consumes the electric current is illegal.The owners of these homes are subject to heavy fines and homes are disconnected from the mains.Because the installation of electricity meters - it's just a necessary measure.
- differences meters work on the principle of
- differences counters other characteristics
- basic rules setting a single-phase meter
- installation diagram of single-phase electricity meter
- What is the installation of three-phase meter
- installation diagram of three-phase electricity meter
Differencescounters the principle of operation
- most common type of meter that is used for many years - mechanical.Second, a more youthful appearance counters - electronic.Mechanical meters operate on the principle of rotation in their round metal elements.The current flowing through the device initiates the movement of the element.Accounting for energy consumption being based on the number of laps revolutions.This type of counter has a lower cost than electronic, the intervals between inspections and their more accurate readings but not always absolutely correct.
- electronic electricity meters operate on a different principle.There are no mechanical parts, and records are maintained by, or semiconductor chips.Lack of mechanics determines the absence of moving parts.Information about the incoming current is passed directly to the voltage sensors.This device has a higher cost, but gives the most accurate result.
- Another important difference counter - number of phases they support.Devices with one-phase and three respectively connected to a network with one or three phases.There are varieties of three-phase devices that connect to the network from a single phase.As for the single-phase meters for three-phase networks, in this case, the devices will need three.
differences counters other characteristics
- One of the main characteristics of that plays into the hands of consumers to electricity - the accuracy of the instrument, or its accuracy.Earlier, this figure ranged from 0.2 to 2.5%.The bulk of the devices had the maximum allowed percentage of inaccuracies in the testimony.But after the government introduced a new accounting standard error for domestic instruments, this figure has decreased to 2%.Accordingly, the most sold devices are just such a figure inaccuracies in their dimensions.
- Another characteristic of household and industrial meters - a way to connect.They are connected directly or via a current transformer.This feature is important when connecting and calculated based on the total load on the electrical network.If this figure does not exceed 100 A, it may be a direct connection method.If the value is exceeded, the necessary additional equipment installation, which has a secondary current of 5 A. When choosing a counter, oriented not only on the total network load, but also on the voltage class of the device.This indicator is often equal to 220, 380 or 100 V.
- Consider voltage class counting the current device is important because it directly affects the type of installation.For example, if the equipment is installed on the high side, the setup is also mounted in the network voltage measuring transformers that the output would yield a value of not more than 100 V. The high side is considered in the event that directly entering the network is from the high-performance line from6 to 10 kW, or if available, high-voltage transformers.
- following characteristics counters - their tariff.The most common in private homes are devices taking into account only one fare.Two-tariff and tariff meters are more expensive and require registration of relevant documents in private homes because they do not use.In addition, for an individual division tariffs are not always available.This is necessary primarily to legal entities, ie various industrial or office buildings.The essence of the tariff meters that he counts on several predetermined rates.For example, the rate of the day and night.
basic rules setting a single-phase meter
Installation and replacement of electricity meters is demanding not only to the circuits, but also to the rest of the steps to set up and prepare for it to be reduced to such rules:
- Selecting the installation room.To install the selected dry rooms, which will not create interference for installation and maintenance of the device.The temperature range from the room may be 0 to + 40C.If the intended installation location does not fit into these parameters, they are organized by the cabinet insulation and heating voltage.
- Selecting a location.There are written rules that determine the possible location of the counter.Installation is allowed to spend on the walls, panels and boards of accounting, in closets, in relay compartments of the switchgear assembly.
- The choice of fixing.Possible options - on metal shields on shields and boxes of plastic, wooden shields.
- Choice mounting height.The optimal distance from the floor is 80-170 cm. The meter should be placed at eye level, it will facilitate his tinning and readings.
- When mounting hardware monitor angle of inclination, it should not be more than 1 °, as the greater slope will create additional uncertainty metering of electric current.This observation is relevant only for induction devices.
- Select size design for installation.Under the structure refers to the niche cabinet or panel, which houses the metering device.The size of the element is selected so as to provide access to all the outcoupling element and to the counter.
- When connecting wires required to take account of their color-coded.All wires cleaned by at least 12 mm.
- breakers must be installed upstream of the meter.This measure will help in the replacement or repair of equipment, as will the ability to turn off the power for a period of work.Controlling energy organizations often make claims of stealing energy if circuit breakers are installed in front of metering devices.To avoid such problems, you must take care of the sealing of the element.To do this, the machine is installed in a special plastic box that has an ear for the seals.
scheme of installation of single-phase electricity meter
When buying electricity meter should pay attention to ready-made electrical pads, which are all necessary components.If there are no guards, then you need to purchase the following items:
- Shield - a box made of wood or plastic, which sets all of the equipment.
- Breakers machines.
- strap mount switches - DIN Rail.
- contact plate, the desired material - copper.This part should be calculated on the accession of at least 10 wires.
- Three-core cable with a cross section of not less than 3 mm, the amount - about 1 m.
- Screws for mounting in a cabinet of all the equipment.Choose products with broad cap of stainless steel, suitable for this purpose and plastic dowels.
Connecting the meter looks like this:
- First we need to pre-allocate all the equipment in the panel to mark a place in every detail to make sure that the compactness of the shield is not dangerous when working with a counter and his service.The allocation of all parts applied so that there is enough space for the fasteners.
- Fix plate, DIN-rail and a counter on the marked places for them.
- Breakers machines fixed to the rail click.
- Getting wiring harness, wiring diagram is as follows:
- Wiring harness starts with the withdrawal phase directly to the circuit breakers of home appliances, which are available in the apartment.These individual circuit breakers equipped with electric stoves, water heaters, floor heating system or auxiliary heating, etc.They are necessary in order not to create surges in the overall network and not to overload it.
- most common phase of the meter is on the three contacts on the left side, but its precise definition is necessary to examine the scheme of the device.To display the phase to individual machines cut the cable jacket and pulled out of his vein of red or brown.Measure the required length of wires, while taking into account, in what plane he will be mounted - either vertically or horizontally.Pull the wire diagonally strictly prohibited.
- extracted from the cable wire trimmed to 2 cm, is inserted into the terminal intended for it and twist fasteners.From the switch machine is cleaning a wire of not more than 1 cm. Further, from the jumper wires are formed into a U-shape, the ends trimmed and connected in all breakers arranged adjacent machines.It is important to ensure that when connecting to the machines they went without overlapping each other, otherwise the connection will overheat.
- phase After connecting the output to zero.For him choose any other color wires.Also, the required length is measured from the electricity metering devices to the copper plate.The most common terminal is zero for the very first to the right terminal or the fourth from the left.Wires for zero cleaned and connect on both sides.
- Shield is attached to the wall after the meter connection.Mark up the mounting location, drill a hole and fasten the shield to the wall with screws.
- Setting ground.For the shields of steel grounding scheme runs counter - shield - contact plate.If the shield is made of electrically non-conductive material, the ground is displayed directly on the plate.
before connecting the meter to the network need to be clarified in the organs of the possibility of independent control of these operations.Most employees of these institutions allow independent installation and only check the correctness of the design and seal up the counter.
What is the installation of three-phase meter
counter with a three-phase system is installed in places that have a high rate of energy consumption.In private households, this figure is not high, because often set single-phase devices.But if consumption exceeds the 10 kW, use a three-phase system.
three-phase system outputs the not usual 220 and 380, which is convenient, and just need to carry out certain work, such as welding.This eliminates voltage swings and machinery in the building on which it is mounted, and adjacent structures.This helps to increase the service life of all electrical appliances and eliminates their breakage at sharp change of voltage.
When you install a three-phase device do not need to install the wiring of a large cross-section, as in this case, the law of Ohm.Devices with the three phases are direct or indirect inclusion.The second option is applicable to current transformers and a very high load on the network.For private households sufficiently direct connection, which operates under a load of up to 100 A, and power up to 60 kW.
scheme of installation of three-phase electricity meter
equipment such as a three-phase electricity meter, optimally establish special boards, which are fixed on the platform and the 3 screws.Mounted equipment fast enough, the algorithm of fixing element is similar to the connection of single-phase meter, and has already been described above, and the scheme of connection looks like:
Wiring in detail:
- supply cable has three phases, the fifth conductor for groundingZero, it enters the electric board.Yellow phase connected to the first contact, the third contact green and red on the fifth.When connecting the phases is important not to make mistakes, otherwise the instrument will generate an error.Determined phase using a special device or by trial and error.That is, after connecting a single phase appliance is checked for errors, and act on, until all wires are connected.
- energy output from the device contacts with the number 2, 4 and 6.
- On 7 and 8 track comes zero.
- Ground, or rather its conductor, is mounted on a special bus.Mandatory bunch of zero to the ground, it protects against over-voltage in the network.
- scheme for the three-phase induction device looks a bit old-fashioned way.Here comes the first phase on the first contact, then made a jumper between this pin and the next, and the phase is already suited to the load from the third.Also connect the rest of the phase - bridge between terminals 4 and 5, 7 and 8. The entrance is at the 4 and 7-pin, and the output 6 and 9.
- New samples of electronic devices equipped with the addition that connects to the network of remote data transmission.This leads to the presence of additional contacts.