I am working with ADE 7880 evb now. The inputs for three channel are all 110 v AC and 100 mA at 50 Hz and voltages and currents are all in phase. there is no harmonic component. Now, I got reading for phase A:
1. why FWATT not equal to AWATT and FVA != AVA?
2. how should I interpret FWATT (and FVA and FVAR) register value as human understandable reading?
3. ADE7880 datasheet gives S = V * I, but here AVA not equal to AVRMS*AIRMS ? Also, FVA not equal to FVRMS*FIRMS.
Note, approximately, AVRMS = FVRMS and AIRMS = FIRMS as expected. when I convert those values to the real voltage and current, I multiply them by voltage and current coefficient factors, for example: AVRMS * V_factor = 0x126048 * 9.396*10^-5 = 113.1556v , which is fine comparing to 110 v input. AIRMS * I_factor = 0x1092C0 * 9.387*10^-8 = 0.10196 A, comparing to 100 mA input.