After getting WH/LSB constant, i need to calculate the WTHR value and write it into the corresponding register inside ADE7880. As the example in ADE7880 calibration app note page 13, Wh/LSB = 9.6262 * 10^-5. From here, what will be the n value in WTHR calculation equation 26 page 47, ADE7880 datasheet. If n = -5 under this case, then can the fact diminishing 9.6262 to 1 cause any error?

Hi Ooben,

For the WTHR value, the suggested value of 0x03 should be entered into the register, as mentioned in the calibration app note, to get the maximum resolution. The equation in the data sheet is more showing a relationship and setting WTHR to a higher value than 0x03 will just decrease the resolution of energy accumulation. The Wh/LSB equation in the application note is to determine the Wh/LSB for a certain load, accumulation time and energy register reading.

Regards,

Dlath