On my project, I use ADE7953. There are two ADE7953 on each board. Actually we treat one ADE7953 metering IC as a mete with two current channels. Channel A and B are fully independent current channel, connect to different load. For calibration, I use accurate current and voltage source.
Upon AN-1118 Application Note (Calibrating a Single-Phase Energy Meter Based on the ADE7953), Figure 4 (page 5) and Figure 8 (page 11), to calibrate current channel B energy registers, we must calibrate BIGAIN using current channel B matching procedure. My questions are:
1. I thought BIGAIN is for current gain adjustment, why should I calibrate BIGAIN for active energy calibration?
2. Does it mean current channel A must be calibrated (including AIGAIN) before channel B calibration since BIGAIN calculation is based on IRMSA and IRMSB reading, is it right? How to calibrate AIGAIN? using equation
IRMSA Expected = IRMSA initial * (AIGAIN / 0x400000)
to calcuate AIGAIN?
3. What is the primary use of AIGAIN / BIGAIN? Upon AN-1118, there is no internal gain calibration register for the rms readings, and on my application, we read IRMSA / IRMSB / VRMS value for current and voltage measurement. Does it mean I must calibrate AIGAIN / BIGAIN in order to calibrate active energy?
Thank you very much for the help.