This section provides overview, applications, and principles of power meters. Also, please take a look at the list of 21 power meter manufacturers and their company rankings.
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A power meter is a device used to measure the power consumed by electrical and electronic equipment (load). A power meter is inserted between a power source and a load and calculates the power from the product of the applied voltage and the flowing current (voltage x current).
In AC, there is a phase difference between the voltage and current, which affects the power, so it is important to measure them at the same time. In recent years, the quality of the power supply has also become increasingly important, and some meters have functions to evaluate the waveforms of voltage, current, and power.
In recent years, reducing energy consumption has become a major theme in addressing global environmental issues, and there is a growing need for electricity meters to check the power consumption of various electrical and electronic equipment. The applications range from general households to save electricity to power monitoring systems for factories and buildings. In addition to measuring power, highly accurate and sophisticated wattmeters are also needed for various evaluations such as phase angle, power factor, harmonics, flicker, distortion, noise, etc., in development and production sites.
Since electric power is the product of voltage × current, it can be calculated by measuring voltage and current, respectively. In the case of direct current, both voltage and current are constant, so power can be calculated by measuring each separately, but in the case of alternating current, the phase difference between voltage and current must be considered, so the instantaneous value of each must be measured continuously at the same timing.
The instantaneous power calculated as the product of the instantaneous values of voltage and current is integrated and averaged over one cycle to give the electric power. This is the power actually consumed by the load and is called effective power. If the effective value of voltage is V, the effective value of current is I, and the phase difference between voltage and current is θ, effective power can also be calculated as V × I × cos(θ).
AC power also includes reactive power and apparent power. Reactive power is the power that travels back and forth between the power source and the equipment without being consumed by the load and is due to the coil and capacitor components of the load. Reactive power can be calculated by V × I × sin(θ). Apparent power must be supplied from the power source, and the relationship equation is: apparent power squared = active power squared + reactive power squared.
*Including some distributors, etc.
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Ranking as of January 2023 Globally
Derivation MethodRank | Company | Click Share |
---|---|---|
1 | Yokogawa Test & Measurement Corporation | 100% |
Derivation Method
The ranking is calculated based on the click share within the power meter page as of January 2023. Click share is defined as the total number of clicks for all companies during the period divided by the number of clicks for each company.Number of Employees
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