How does an AC meter work What is the working principle of an electricity meter?

The amount of current passed per minute.

Electricity is the basic daily expenses of residents, very sensitive to its cost, if more than one month will be very concerned, will think about whether there is something wrong with the meter, there will be people to study the meter, think of various ways to make the meter go slower, in fact, these methods are not only illegal but also damage the meter, do not do this.

The meter is used to measure the electric energy consumed in a certain period of time, or the meter used to consume electric energy on the load, it is a metering device, the unit of measurement of the meter is kilowatt-hour (that is, 1 degree), so it is also called the kilowatt-hour meter, or the electric energy meter, the watt-hour meter, which is widely used in various fields of society.

Electricity meters are divided into different types according to different uses, structures, accuracy, power supply properties, etc., and we are commonly found to be ordinary single billing meters.

The advent of electricity meters has been around for more than a hundred years.

In 1881, the principle of electrolysis was used to make a direct current energy meter, which was billed by the hour.

In 1885, with the invention and application of alternating current, the alternating current meter was born.

In 1889 the first inductive meter appeared, but it was also very large and weighed kilograms.

Since the beginning of the 20th century, with the development of technology and processing, the size and weight of electricity meters have been decreasing.

In the 60s of the 20th century, with the development of electronic technology, the digital meter was invented.

At the end of the 20th century, with the construction of smart grids, the function of electricity meters has become more and more powerful, and there have been functions such as time-based billing, prepayment of electricity cards, and detection of power grid operation status, and smart meters have emerged.

In 1879, China's first electric lamp appeared in Shanghai, at that time, it was charged according to the monthly fee of the lamp head, and later the electricity was popularized and changed to electricity meters, but they were all imported from abroad.

In 1966, China's first domestically produced electricity meter was born in Shanghai.

After decades of development, with the construction of smart grids, smart meters have gradually entered thousands of households.

Many people are curious, how does the meter calculate the amount of electricity consumed?

Mechanical meters.

When the electrical equipment begins to consume electric energy, the current passing through the meter energizes the voltage coil on the aluminum disc and connects it in parallel with the electrical equipment, and the current coil below energizes it and connects it in series with the equipment used.

The two coil circuits generate magnetic flux, interact with the current induced by it on the aluminum disk, produce a rotating torque, thereby driving the aluminum disc to rotate counterclockwise, at this time the brake magnet also interacts with the rotating aluminum disc to produce braking torque, when the two moments reach equilibrium, the aluminum disc rotates at a stable speed, the greater the power consumed by the equipment, the greater the current through the coil, the greater the rotating torque of the aluminum disk, and the faster the aluminum disc rotates.

The rotating aluminum disc drives the turbine rod gear mechanism to drive the counter to count and complete the calculation of the power consumption of the electrical equipment.

The traditional watt-hour meter refers to the inductive mechanical watt-hour meter (referred to as the induction meter or mechanical meter), which uses the principle of electromagnetic induction, and is mainly composed of voltage coils, current coils, aluminum discs, permanent magnets, meters and other devices. Its working principle is: according to the principle of electromagnetic induction, when the meter is energized, the electromagnetic field is generated in the current coil and the voltage coil, and the rotating torque is formed on the aluminum disk, and the meter is driven to count through the transmission gear, the larger the current and voltage, the greater the torque, the faster the counting, and the more electricity is used.

The rotational torque of the aluminum disc is directly proportional to the active power of the load. The meter constant refers to the number of revolutions of the aluminum disc corresponding to the measurement of each unit of electric energy value (kWh or kW·h), and the unit is kW·h.

2) "Basic Principles of Electronic Watt-hour Meters".

The electronic watt-hour meter uses an electronic circuit chip to measure electrical energy; Use a voltage divider resistor or voltage transformer to turn the voltage signal into a small signal that can be used for electronic measurement, use a shunt or a current transformer to turn the current signal into a small signal that can be used for electronic measurement, use a special electric energy measurement chip to convert the converted voltage and current signals for analog or digital multiplication, and accumulate the electric energy, and then output a pulse signal whose frequency is proportional to the electric energy; The pulse signal drives the stepper motor to drive the mechanical meter display, or sends it to the microcomputer for digital display after processing.

The working principle of the electric energy meter is: when the electric energy meter is connected to the circuit under test, there is alternating current flowing in the current coil and voltage coil, and the two alternating currents produce alternating magnetic flux in their cores respectively; The alternating magnetic flux passes through the aluminum disc and induces eddy currents in the aluminum disk; The eddy current, in turn, is subjected to force in the magnetic field, which causes the aluminum disc to obtain torque (active torque) and rotate. The greater the power consumed by the load, the greater the current through the current coil, and the greater the eddy current induced in the aluminum disc, the greater the torque that makes the aluminum disc rotate.

That is, the magnitude of the torque is proportional to the power consumed by the load. The higher the power, the greater the torque, and the faster the aluminum disc will rotate. When the aluminum disc rotates, it is affected by the braking torque generated by the permanent magnet, and the braking torque is opposite to the direction of the active torque; The size of the braking torque is directly proportional to the speed of the aluminum disc, and the faster the aluminum disc rotates, the greater the braking torque.

When the active torque and the braking torque reach a temporary balance, the aluminum disc will rotate at a constant speed. The electrical energy consumed by the load is directly proportional to the number of revolutions of the aluminum disc. When the aluminum disc rotates, the counter is driven to indicate the electrical energy consumed.

This is the simple process of working with an energy meter.

Hello, it's a pleasure to be able to help you. The working principle of the electricity meter is as follows: The ammeter is made based on the action of the energized conductor in the magnetic field by the force of the magnetic field.

There is a permanent magnet inside the ammeter, which generates a magnetic field between the poles, there is a coil in the magnetic field, there is a hairspring spring at each end of the coil, the spring is connected to a binding post of the ammeter, between the spring and the coil is connected by a rotating shaft, and there is a pointer at the front end of the rotating shaft relative to the ammeter. When there is a current passing through, the current passes through the magnetic field along the spring and the rotating shaft, and the current cuts the magnetic inductance line, so it is affected by the magnetic field force, which makes the coil deflect, and drives the rotating shaft and pointer to deflect. Since the magnitude of the magnetic field increases with the increase of the current, the magnitude of the current can be observed by the degree of deflection of the pointer.

Working principle: connect the meter on the circuit, the circuit voltage will be added to the voltage coil of the meter, and the circuit current will generate variable magnetic flux through the coil, pass through the aluminum disk, and form an eddy current on the aluminum disk.

At this time, the eddy current reacts with the magnetic flux to rotate the aluminum disk, which will cut the magnetic flux of the brake magnet and induce an electric current. At the same time, the current and magnetic flux interact to make the aluminum disc rotate at a constant speed.

The use of the universal meter is to check whether there is a problem with the appearance first, then turn on the switch, connect the measurement ends to the universal meter, and also measure the value of resistance and voltage by adjusting various buttons, which can be AC or DC. Here's how:

Tool: Magnum.

1. Measurement of resistance value When measuring, the black table pen is connected to the COM jack, and the red table pen is connected to the V jack, and the resistance gear is greater than the measured resistance value.

2. When measuring DC voltage, the black meter pen is connected to the COM jack, and the red meter pen is connected to the V jack, before measuring the DC voltage, the transfer switch is turned on to the appropriate range of the DC voltage DCV according to the value of the measured voltage, and the two meter pens are connected to both ends of the tested power supply, the black meter pen is connected to the negative pole, and the red table is connected to the positive pole with the pen to read the DC voltage value of the tested power supply.

3. To measure the AC voltage, first estimate the size of the measured voltage, turn on the gear switch to the AC voltage range, which is greater than the estimated voltage value in the gear, such as judging that 220V should be opened to 600V gear.

4. The beep file of the universal meter is used to check the on-off of the line, and the symbol is the symbol of a diode, and there is a similar and wireless logo next to it to convert the gear to the beeping file.

Notes:

When measuring the AC voltage, do not touch the metal part of the pen with your hands to prevent electric shock, and you must have the safety awareness of doing experiments when doing experiments.

Electronic smart meter is a high-tech product developed in recent years on the basis of electronic meter, and its composition and working principle are very different from the traditional inductive energy meter. The electronic smart meter is mainly composed of electronic components, and its working principle is to first use the user's real-time sampling of the power supply voltage and current, and then use a special electric energy meter integrated circuit to process the sampling voltage and current signal, and convert it into a pulse output proportional to the electric energy, and finally process and control it through a single-chip microcomputer, and display the pulse as the electricity consumption and output.

Energy meter (watt-hour meter): A meter that measures the amount of electrical energy consumed by an electrical appliance. 1 kWh 1 kWh 1000 watts 3600 seconds = joules.

For example, how many hours can 1 kWh of electricity make two "220V, 40W" lights work?

Solution t w p 1 kWh (2 40 watts) 1000 watt hours 80 watts = hours.

The speed of the energy meter is related to the power of the consumer, the more powerful the electrical appliance is working, the faster the disk of the energy meter rotates.

Significance of important parameters:

1. "220V" - means that the energy meter should be used in the circuit of 220V.

2. "10 (20A)" - means that the calibrated current of this electric energy meter is 10A, and the rated maximum current is 20A (where 20A is not the maximum current allowed in a short period of time but the rated maximum current).

3. "50Hz" - means that it is used in 50Hz AC circuit.

4. "600revs kw·h" - means that for every 1 kilowatt-hour of electrical energy consumed, the turntable on the energy meter turns 600 times.

It is calculated according to the number of revolutions rotated by the turntable of the energy meter. If the energy meter is marked with "600revs kw·h", when the turntable turns n times, the energy consumed is w=nr 600r kw·h=n 600.

1. According to the principle of electromagnetic induction, when the meter is energized, the electromagnetic field is generated in the current coil and the voltage coil, and the rotating torque is formed on the aluminum disk, and the transmission gear is counted by the transmission gear belt, the larger the current and voltage, the greater the torque, the faster the count, and the more electricity is used. The rotational torque of the aluminum disc is directly proportional to the active power of the load. The meter constant refers to the number of revolutions of the corresponding aluminum disc when measuring the value of each unit of electric energy.

2. The basic principle of the electronic watt-hour meter, the electronic watt-hour meter is to use electronic circuits and chips to measure electric energy, use a voltage divider resistor or voltage transformer to turn the voltage signal into a small signal that can be used for electronic measurement, use a shunt or current transformer to turn the current code signal into a small signal that can be used for electronic measurement, use a special electric energy measurement chip to convert the converted voltage and current signals for analog or digital multiplication, and accumulate the electric energy, and then output a pulse signal whose frequency is proportional to the electric energy; The pulse signal drives the stepper motor to drive the mechanical meter display, or sends it to the microcomputer for digital display after processing.

3. The principle of mechanical watt-hour meter is based on Chi Shu, and the traditional watt-hour meter refers to the inductive mechanical watt-hour meter, referred to as the induction meter or mechanical meter, which uses the principle of electromagnetic induction, which is mainly composed of voltage coils, current coils, aluminum disks, permanent magnets, meters and other devices.

You only need to see with your eyes, and you don't need to grind your own clothes. The electric energy meter is installed by the power supply department, and the display and billing program parameters are set, and the data is automatically uploaded or read by the charging department, and the user cannot operate it.

If the user wants to know how much electricity is used, he can read the two readings of "current combined active power" and "last month's combined active power" in its cycle display, and the difference between the two numbers is how many kilowatt-hours of electricity used this month. Shown here are 8 digits, with the first 6 digits being integers and the last 2 decimal places. The unit is kWh, which is the number of degrees of electricity.

Electricity is a natural phenomenon that refers to the phenomenon caused by the movement of electric charges. Lightning in nature is a phenomenon of electricity. Electricity is a property of the repulsive force and attraction that arises between subatomic particles like electrons and protons.

It is one of the four basic interactions in nature. There are two phenomena of electron motion: atoms that lack electrons are said to be positively charged, and atoms that have excess electrons are said to be negatively charged.

Electricity is a general term that is a physical phenomenon produced by a stationary or moving electric charge. In nature, the mechanism of electricity gives many well-known effects, such as lightning, triboelectric induction, electrostatic induction, electromagnetic induction, and so on.

electrostriction, piezoelectric effect (electrical and polarity of mechanical pressure on a dielectric crystal) and inverse piezoelectric effect, Seebeck effect, Peltier effect (at the junction of two different metals or semiconductors, heat is released when an electric current passes in a certain direction, and heat is absorbed when the current is reversed);

The Thomson effect (a metal conductor or semiconductor maintains a temperature gradient that releases heat when an electric current passes in a certain direction and absorbs heat when the current is reversed), thermistors (the resistance in a semiconductor material changes with temperature), photoresistors (the resistance in a semiconductor material changes sensitively with light), photovoltaic effect (a potential difference in semiconductor materials due to light), and so on.