Submitted by TrystanLea on Mon, 12/14/2009 - 12:58.
Hello Charles and dubbleUJay, Thanks for the suggestion Charles. I have been using zero-crossing detection on the voltage signal to measure frequency but haven't tried to use it to measure power factor. I think it might be challenging however since the current signal is often much less sinusoidal and so the point at which it crosses zero isn't so "clear" as the voltage signal. I tried to measure the frequency from the current signal and found that that was a problem.
Ive been measuring the voltage signal with a step down AC to AC transformer recently and then calculating the power factor by dividing the real power by the apparent power, seems to be working nicely, need to document it next and put it up here :)
Trystan
Hello Charles and dubbleUJay,
Hello Charles and dubbleUJay, Thanks for the suggestion Charles. I have been using zero-crossing detection on the voltage signal to measure frequency but haven't tried to use it to measure power factor. I think it might be challenging however since the current signal is often much less sinusoidal and so the point at which it crosses zero isn't so "clear" as the voltage signal. I tried to measure the frequency from the current signal and found that that was a problem.
Ive been measuring the voltage signal with a step down AC to AC transformer recently and then calculating the power factor by dividing the real power by the apparent power, seems to be working nicely, need to document it next and put it up here :)
Trystan