Electricity meters are the most popular meter in the household spectrum. They are used in every home as a means of controlling the amount of electricity consumed. Another thing is that the technical execution of the design may be different. The traditional and still quite common types of this device include an electric induction meter, which also provides for various forms of technical and structural implementation.
Definition of induction meters
Like all electricity meters, induction models provide for the passage of current through their conductors with the connection of sensitive measuring elements. They differ in capacity, size, maximum load, etc. First of all, the induction counterelectricity is a mechanical device provided with a counting mechanism. Again, technically, its "stuffing" can have a different design, but the basic principles are guided by the electromagnetic principle of operation, which allows you to fix the behavior of eddy currents over a magnetic field.
Technical device and principle of operation of the device
The basis of the device is formed by two elements - coils for servicing voltage and current. The first is connected in parallel, and the second is connected in series. Together they create conditions for electromagnetic flows, in the environment of which, in principle, it becomes possible to fix with the measurement of the necessary parameters of the network. Directly measuring operations are carried out at the expense of an aluminum disk. By means of a worm or gear drive, this element is mated with a counting device, putting it into action. During operation, the intensity of disk rotation will be determined by the power consumption. The modern device of the induction meter is also distinguished by the presence of electronic elements that make it possible to automatically register readings, remote control of individual metering parameters and reduce the size of the panel with the display of information on consumption. But even in this case, the basic principles of electromagnetic measurement by inducing coils are preserved.
Creating a counter
The first electromagnetic meters appeared at the end of the 19th century, when Italian engineers discovered the relationship between different phases of AC fieldscurrent and magnet. In the manufacture of the simplest structures, a solid rotor was used like a cylinder and the same disk. It was set in motion by changing electrical characteristics. The next step was the development of a full-fledged screw mechanism, but so far without voltage control elements. Actually, at this stage, the principles of operation and the technical device of a modern induction meter with self-induction coils and a rotating metal body were laid. In the future, the design was replenished with brake electromagnets, which made it possible to expand the measurement range with a cyclometric register. The entire 20th century was the process of optimizing the case, which led not only to the optimization of the dimensions of the device, but also to an increase in the reliability of the elements of the counting mechanism. Structures have become more resistant to temperature, humidity and physical influences. The accuracy of readings has also increased, which is especially evident in the latest generation devices with new functionality and control approaches.
Induction meter classifications
First of all, one should distinguish between single and three-phase models. The first refers to household measuring instruments intended for home use. They are powered by a single phase and have 4 terminals. You can connect such a device to a common main power supply. As for three-phase induction meters, they have a higher level of reliability and are divided into groups depending on the operating conditions. So,There are models for use at home, in factories and in public places. Moreover, in the domestic sphere they are usually used if a powerful energy consumption infrastructure is organized with the connection of productive equipment such as welding machines, compressor stations, pumping units, etc.
Within the general family of induction metering devices, the already mentioned mechanical and electronic types of models are also distinguished. Mechanics has its advantages associated with low energy dependence and structural reliability. Electronics, in turn, makes it possible to differentiate the consumption of energy, which is convenient when using electricity at several tariffs depending on the consumer.
Instrument Specifications
Voltage is the main characteristic of electrical meters. The standard range varies from 220 to 240 V, which corresponds to the capabilities of single-phase models. In the case of three-phase meters, we can talk about 380-400 V. The maximum current load is also taken into account in the choice of an induction device. The nominal value must exceed the amount of current that the introductory machine allows. For example, if a 25-30 A transformer is used, then it is advisable to install an induction meter of at least 40 A. At the household level, the maximum indicators for this characteristic rarely exceed 100 A.
For a private house, it is quite possible to limit yourself to buying a model for 40-60 A. It will also be usefulpay attention to the accuracy class. In principle, the rules do not allow the operation of metering devices with a coefficient of more than 2.0. The best option is to purchase devices with an accuracy class of 1.0. This is important not only because of obtaining more correct data on consumed energy, but also for objectively monitoring the operation of a home or industrial electrical network.
Meter operation
After choosing a suitable model, a place is selected to install the device. It is desirable that it be protected from physical, thermal and electromagnetic external influences. Mounting is usually carried out using a DIN rail and a complete set of hardware. The rail is supplied with a block with terminals, which can be separate or built-in. In any case, through it, the device is integrated into the local power grid. The connection is made by employees of the power supply company, who will also periodically check the status of the device.
The nuances of the operation of induction meters
During the operation of measuring devices of this type, the following features of the workflow should be borne in mind:
- At low loads in the network, it is possible that the accuracy will decrease below the standard level, so it is recommended to monitor the parameters of the same voltage using a stabilizer.
- Without the presence of mechanical means of protection, the operation of the induction meter can be corrected physically. To fix suchcases, the devices are sealed. By the way, electronic induction meter models are protected from all kinds of "twisting" programmatically.
- High maintainability. Even in the event of damage to internal energy controls, it remains possible to restore full functionality by replacing failed components.
The future of induction metering technology
Despite the moral obsolescence of the principles of electromagnetic accounting, manufacturers do not abandon this segment, endowing devices with new functionality. Prospects for the development of an induction meter are primarily associated with digital means for processing and sending data. Already today there are models with GSM-sensors, which completely save the user from analog recording of accounting information. The range of basic functions is also expanding. This set is expanded with the ability to register frequency, voltage and external microclimatic indicators.
Conclusion
Induction measuring equipment today is widely used not only in domestic and commercial areas, but also in industry. And this applies to both three-phase and single-phase induction meters with electronic "stuffing". Such a choice is determined by the high requirements for the reliability and reliability of the operated power systems. However, there are still problems with the use of induction devices. Negative factors relate to a relatively low degree of accuracy, sensitivity to network loads and poor protection againstelectricity theft.
