Electric energy meter
is an instrument used to measure electric energy, also known as watt - hour meter, fire meter and kilowatt-hour meter. It refers to an instrument used to measure various electrical quantities.
Electric energy meter (can be divided into coin – operated meter, magnetic card – operated meter, and electric card – operated meter), loss electric energy meter, multi-function electric energy meter, and intelligent electric energy meter.
According to the working principle: it can be divided into inductive (mechanical) meter, static (electronic) meter and electromechanical integrated (hybrid) meter.
According to the nature of the connected power supply: it can be divided into AC meter and DC meter.
According to structure: it can be divided into integral meter and split meter.
According to access phase line: it can be divided into single phase meter
, three phase meter
and three-phase four-wire electric energy meter.
According to the accuracy level: it can be divided into electric energy meter with common installation (level of 0.2S, 0.5S, 0.2.0.5.1.0, 2.0) and portable precise electric energy meter (level of 0.001, 0.005, 0.2).
According to the installation and connection mode: it can be divided into direct access meter and indirect access meter.
Active energy meter
Electric energy can be converted into various energies. For example, it is converted into heat energy by electric furnace, mechanical energy by electric motor and light energy by electric lamp. The power consumed in these conversions is active power. The meter recording this kind of electric energy is an active electric energy meter.
The electrical principle tells us, some electrical devices of electric energy meters need to establish a conversion environment before energy conversion, such as motors, transformers, etc. need to establish a magnetic field before energy conversion, while some electrical devices need to establish an electric field before energy conversion. The electric energy needed to establish the magnetic and electric fields is reactive power. The meter that records this kind of electric energy is reactive power meter. Reactive power does not consume energy in the electrical device itself, but it will generate reactive current in the electrical circuit, which will cause certain losses in the circuit. Reactive power meters are designed to record this loss and are usually installed only in large power consuming units.