Hello,

Could you say me, how the active power (W) and FP are calculated ? Today, electric load are non linear, can you use FFT algorithm ?`

regards

stef

# True RMS : what kind of measure?

**stef30360**#1

**overeasy**#2

Per sample wave, defined as the time when voltage crosses zero until it crosses again two more times:

- Voltage and current pairs are sampled every 26μs.
- RMS voltage is the Root of the Mean of the Squares of the voltage samples.
- RMS current is the Root of the Mean of the Squares of the current samples.
- Real (active) Power is the mean of the product of voltage and current of each sample.
- Everything else can be derived from those measurements.

There is no FFT calculation.