To control the cost of electricity in apartments of high-rise buildings, an electronic electricity meter is used. The digital device is connected via a common transformer. During operation, the meter constantly measures the power of a given section of the network and displays its value in a readable form.
Design and principle of operation
The measuring device is compatible with single-phase and three-phase AC circuits. Its design is represented by:
- housing made of heat-resistant plastic or metal with a terminal block;
- display - an LCD indicator where data and time are displayed, or mechanical;
- power source of the electronic circuit;
- current transformer - performs the functions of a meter;
- a microcontroller that converts the input signal to electrical quantities;
- telemetric output for integration with ASKUE;
- hours - allow you to track real time and dates;
Appearance of an electronic electric meter - supervisor - monitors voltage fluctuations at the input and issues a reset command to the microcontroller when the voltage turns off or on;
- management system;
- optical port that allows you to take readings of the device.
A digital counter can be programmed through the optical port.
The principle of operation of the digital electricity meter is a direct measurement of voltage and current. He digitizes the information, passing it to the indicator and storing it in memory. The pulses of the input electronic solid-state elements create under the influence of a voltage current. The number of pulses depends on the activity of energy.
Key Features of Digital Meters
In the territory of the Russian Federation, devices began to be used from the moment of privatization of the energy industry and the rise in price of electricity. Electronic devices have a number of positive characteristics:
- accuracy of readings during a rapid change of voltage or its decrease;
- electricity metering at several tariffs;
- counting various types of energy using one apparatus;
- simultaneously measured power, quantity and quality of energy resources;
- storing data in memory and having user access to it;
- prevention of unauthorized access and theft of electricity;
- remote reading and preliminary calculation of losses;
- compatibility with automatic services of commercial electricity metering.
The device cannot be cracked by intruders and connected to it to steal electricity. The product inspection interval is 16 years.
Differences between electronic and induction meters
Induction models work on the principle of creating an electromagnetic field in a coil and its interaction with a conductive disk. A single-phase device is connected to the AC coil in parallel. Magnetic fluxes and eddy currents interact with each other only in the disk. The induction meter will function normally with a phase shift of 90 degrees. Energy consumption depends on the intensity of rotation of the disk, which corresponds to the power consumption.
The principle of operation of the electric meter is based on calculations of the power of the active and reactive types. This allows you to accurately calculate energy consumption, if the room has a three-phase type of connection.
Induction models consider consumption at a single rate, digital devices track parameters depending on the time of day. Measurement accuracy of the new counter is the 1st category, traditional ones are issued with an accuracy class of 2.5.
Compared with an induction digital meter, it uses a minimum of energy resources for its own needs. Traditional devices cannot be installed externally, while electronic devices can work in freezing conditions and are protected from moisture and dust.
Reliability of indications and the need for repair
A high-quality digital electric meter is highly accurate. Check the parameters without violating the integrity of the housing and seals as follows:
- After the power is cut off, the indicator stops. If accounting continues, the device is malfunctioning.
- The meter always buzzes at work, self-propelled devices indicate malfunctions.
- The readings are distorted when all household appliances are turned off. Be sure to check the presence of self-propelled.
Testing is best done at night, with minimal load on the power grid. If there is no self-propelled device, there are no indicator pulses for 15 minutes. An impulse that occurs when the connection is not made means a breakdown.
Only a energy-saving company should repair a digital meter. The user contacts the authority to obtain permission to check and replace the device.
Designation of indicators of a digital counter
Based on the data of the electronic meter, several indications are determined:
- Energy costs for a specific time period. It will be necessary to subtract the initial ones from the final readings. If necessary, the calculated data is multiplied by the transformation coefficient;
- Connecting household appliances and lighting at some point. It is set by light on / off of the indicator light.
- Power parameters, passing current, network and meter overload processes.
Digital devices can be programmed for daily and night billing. To do this, just select the counting time.
Selection criteria
Before buying a device, you should pay attention to a number of parameters:
- Permissible current value. Digital models are designed for a current of 5-60A, which is suitable for apartments and private houses.
- Date of verification. On a three-phase meter there should be a seal no older than 1 year.
- The number of fillings. The first sealing is done by state bodies - a mark is put on the casing. The second seal on the clamping cover is from the power supply company.
- Optional. The more features, the more expensive the counter. But the internal tariffifier creates a load schedule, and in the event log there is an increase and decrease in voltage in each phase.
- Service and Warranty. Quality models have a long warranty period. The brand service center is in the buyer's city.
- Check interval. Optimal - from 10 to 16 years.
- Integration with ASKUE. Readings are automatically transmitted to the provider.
- Phase. Information is indicated on the scoreboard. A single-phase device is marked 220 or 230 V, three-phase - 220/380 V or 230/400 V.
- The number of tariffs. The two-tariff scheme eliminates overpayments for electricity at night.
- Mounting method. The digital apparatus is mounted on screws (enclosure S or W) or DIN rails (enclosure R or P).
The seller is obliged to stamp the device and record its starting readings.
List of the best metering devices
Consumers and professional electricians recommend several devices.
Mercury 201.8
Durable budget device with a 7-bit LCD screen resolution and accuracy class 1. Designed for a network with a voltage of 220-230 V and a current of 5-80 A. It works properly in conditions of heat and frost with humidity up to 90%. Equipped with:
- modular housing;
- measuring current converter;
- screw terminals;
- LED illumination of a zone of indications.
The operational life of the model is 30 years, the revision period is 16 years.
Neva M.V. 123
A device with an operating voltage of 230 V and a rated current of 5 A. The manufacturer's warranty is 30 years. Designed to measure:
- mains voltage frequencies;
- active power of the electric line;
- indicators of current voltage and strength.
The model has 1 accuracy class, it can be installed in offices, houses, trading floors and apartments.
Energomera CE102M S7 145-JV
The accuracy class of the model is 1. It is not subject to climatic, electromagnetic and mechanical damage. The device is designed for a current strength of 5-60 A, an operating voltage of 220-230 V. It can operate without failures at a temperature of -45 to +70 degrees and a humidity of 98%. Additional features:
- tongue;
- non-volatile memory type;
- communication interfaces;
- user reprogramming;
- data output for the desired period of time;
- removal of information without stress.
No corrections can be made to the counter memory.
Electronic meters are modern accounting devices with wide functionality. They guarantee measurement accuracy, are reliable and resistant to external influences.
