Page History: Measuring RMS (algorythm) using MMBasic
Compare Page Revisions
Page Revision: 2020/07/25 19:36
The RMS value of is the Root-Mean-Square value. It is essential for determining power dissipation in circuits.
Determining RMS value of an AC signal measurement has been a challenge for multimeter designers for years. Since the RMS value of a signal was used to determine disspation, it is not strange that the earliest RMS meters contained a dissipating element, and the RMS value was derived from the temperature rise of the heating element.
Since the advance of semiconductors, and especially analog IC's, RMS was determined by actually multiplying a voltage with itself, filtering, and taking the square root.
To get an acceptable resolution, the analog circuits needed a low noise floor, great linearity. Needless to say these chips where expensive.
With the introduction of digital electronics, and ADC's, life go soo much easier.
Below is a method of implementing RMS measurements on a mains AC signal, with minimal external circuit, in MMBasic on a small micromite.