As you know, calibration is a must for every energy meter to prove its accuracy. In the evaluation code for sure there are the sections for sigma-delta analog to digital converter, calibration code, read values for current and voltage as well.
I have been always focused on the kWhs amount without caring about what I read for voltage and current. But I know if the current and voltage values are not accurate I read wrong kWhs!
Evaluation board itself has no Load on it and you need to get CTs worked to calculate kWhs. Instead we use shunt resistors plus some other resistors to have kWhs accumulations. Now it is time to test the accuracy!
In your opinion, what are the most important factor should I put in mind?
1. Analyzing how to measure current and voltage?
2. Find calibration factors in the code?
or else?
How do you calibrate and make sure the meter works properly?