RMS value calculation

The rms value for voltage and current is calculated over a measuring interval, in this case the period T. The following equations are used:

u_(t): instantaneous voltage value
i_(t): instantaneous current value
n: number of measured values

Measuring interval

The choice of the right measuring interval is important for the quality of the measurement. The default setting for the measuring interval is 10 periods (10 x 20 ms). Experience shows that this is a good compromise between measuring speed and stability. Deviations from this value are only advisable in the event of particular measurement requirements (e.g. high measuring speed).