Electric meters can also be called ammeters. With the development of the economy, society, and the times, the styles and functions of electric meters are increasing. Next, talk about the working principle of kilo watt-hour meter .

When the meter is connected to the circuit under test, alternating current flows through the current coil and the voltage coil. These two alternating currents respectively generate alternating magnetic fluxes in their iron cores; the alternating magnetic flux passes through The aluminum disk induces eddy currents in the aluminum disk; the eddy currents are subjected to force in the magnetic field so that the aluminum disk obtains torque (primary torque) and rotates. When the aluminum disc rotates, it is acted by the braking torque generated by the permanent magnet. The braking torque is in the opposite direction of the main torque; the magnitude of the braking torque is proportional to the rotation speed of the aluminum disc. Bigger. When the main torque and braking torque reach a temporary balance, the aluminum disk will rotate at a constant speed. The electrical energy consumed by the load is proportional to the number of revolutions of the aluminum plate. When the aluminum plate rotates, it drives the counter to indicate the power consumption.

In fact, the working principle of electricity meters is similar, and the more popular three phase electricity meter is also the same.