enter image description here I am working on a power meter project with ZMPT101B and SCT013. I want to see the phase difference between voltage and current in the serial plotter but the results are like this? Why do you think the current reading is not a sine like a voltage wave?] 2]2

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    because there is only a little load – Juraj Jun 19 at 9:27
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    When you look closely, the current is oscillating too. The signal is just too small to see it here. You should try to scale it up and/or make a measurement with more resolution – chrisl Jun 19 at 10:33
  • Current is only a sine wave with a purely resistive load. With other loads current changes all the time depending on what the load(s) is(/are) doing. – Majenko Jun 19 at 11:52
  • @Majenko and isn't it true that there is no such thing as a purely resistive load? There's always going to be some inductive and capacitive component, albeit a small one. – Duncan C Jun 19 at 13:18
  • @DuncanC Often too small to measure though, at least with crude sensors like the SCT013, which itself will be an inductive load, thus changing your measurements by doing the measuring. But yes, it's impossible to get 100% pure resistive. – Majenko Jun 19 at 13:56

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