Mains AC: non-invasive version 3.0 up

The documentation for version 3 of the Mains AC: non-invasive energy monitor is up. It can be found here:

Mains AC: non-invasive version 3.0

The main changes are:


  • 2x 10uF bias stabilizing capacitors added significantly improving accuracy: more info
  • Changed Voltage measurement circuit
  • Power for arduino comes from a seperate transformer to AC voltage measurement transformer.


  • Arduino sketch rewrite, sketch now follows Atmel's AVR 465 app note method, adding:
    • Phase calibration
    • Digital high pass filter to remove offset.


  • Much simplified calibration
There is also new more detailed documentation with this version, including separate pages on:

I've also done a bit of re-arranging of the documentation layout, trying to make the website a little easier to navigate, if you have any suggestions on this they would be very welcome.
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