The difference of the measuring device Rms & True Rms
RMS and True RMS are two commonly used techniques for measuring AC voltage and current in electrical engineering. Although both methods provide an estimate of the magnitude of an AC signal, they differ in their measurement approach and the types of signals that can be accurately measured.
RMS, or Root Mean Square, is a method for determining the equivalent DC value of an AC waveform. This method calculates the square root of the average of the signal’s squared values over time. As the resulting number is proportional to the heating effect of the AC signal on a resistive load, it can be used to calculate power. However, RMS measurements assume that the waveform being measured is a pure sine wave, which can lead to inaccurate results for non-sinusoidal waveforms.
True RMS is a more precise measurement technique that can provide accurate measurements for both sinusoidal and non-sinusoidal waveforms. This method calculates the RMS value of an AC signal after it has been converted to a DC signal with the same heating effect. This enables precise measurements of signals with harmonic distortion, which can be difficult to measure using RMS measurements.
In conclusion, while both RMS and True RMS are effective for measuring AC voltage and current, True RMS is the more accurate technique for measuring non-sinusoidal waveforms. To obtain precise and reliable results, it is important to choose the appropriate measurement technique based on the specific waveform being measured.
Examples to RMS and True RMS Devices
In the following, we will introduce RMS and True RMS devices. FLUKE 376 FC Clamp Meter and HIOKI DT4256 DIGITAL MULTIMETER are examples of True RMS devices, while Fluke 15B+ Digital Multimeter and Hioki 3280-10F CLAMP METER is an example of an RMS device.
