1, Ordinary electric meter (Carousel meter)
The working principle is: When the watt-hour meter is connected to the circuit under test, there is an alternating current in the current line and the voltage line, and the two alternating currents respectively generate alternating magnetic flux in their cores ; Alternating magnetic flux through the aluminum plate, induced in the aluminum plate vortex; eddy currents in the magnetic field by force, so that the aluminum plate torque (active moment) and rotation. The greater the power consumed by the load, the larger the current passing through the current line, the larger the induced eddy current in the aluminum plate, and the larger the moment of rotation of the aluminum plate. The size of the torque is proportional to the power consumed by the load. The greater the power, the greater the torque, the faster the aluminum disk rotation. Aluminum plate rotation, but also by the permanent magnet brake torque generated by the role of the braking torque and the direction of the opposite direction of the active torque; brake torque and aluminum plate is proportional to the size of the speed, the faster aluminum plate rotation, the braking torque is also The bigger When the driving torque and braking torque to achieve a temporary balance, aluminum plate will rotate at a constant speed. The power consumed by the load is proportional to the number of revolutions of the aluminum plate. When the aluminum plate is rotated, the counter is driven to indicate the consumed power. This is a simple process meter work.
2, Smart meters (Electronic meter)
Full electronic meter works The basic principle of electronic meter is real-time power supply voltage, current and current sampling, calculation, non-professionals may not understand, for example, the equivalent of your use of voltmeter, Ammeter continuous 24h recording voltage and current readings, but also the relationship between the two have to record, according to this series of data eventually converted into power consumption. Of course, in practice, real-time conversion, measurement speed is thousands or even more per second!
These tasks are done by the internal microprocessor, which is the so-called micro-computer, because there is no mechanical transmission and those electronic circuits, micro-circuit power consumption can be done very low, even micro-ampere meter, So he is very power-saving, this is one of the advantages.