Hi,

I am using ADE7758 to measure the V, I and Energy. Up to now, I am able measure Real Power (AWATTHR) and Apparent Power (AVAHR) using the line cycle accumulation method using the steps shown in page 49 of the datasheet. However, for the next step of measuring the Reactive Power (AVARHR), I am having some difficulties. According to the datasheet on page 48 Figure 81, inductive load of power factor 0 is needed in order to calculate the AVAR gain. My concern is getting the inductive load of zero power factor to obtain the test system. May I know any easily available equipment that is suitable for this case?

Thanks.

Regards,

Kristin

Hi Kristin,

You could use a 2-channel waveform generator to directly input the +/- 500mV (max value) sine waves into the input circuitry of you ADE7758. It is just important that the 2-channels can be synced in order to put a known 90 degree delay between the voltage and current waveforms.

If this is not available and you can get a load with PF = 0.5 then it would be ok to use that for calibrating xVARG, just be sure to use the angle of 60 degrees in the calculation of VARHRexpected. This should be sufficient for gain calibration.

Regards,

David