
Non-Invasive Power Monitor - ericdanielski
https://www.matthuisman.nz/2018/06/non-invasive-power-monitor.html
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bertjk
For those interested in paying for a product that does something like this,
there is [https://sense.com/](https://sense.com/) for residential or
[http://verdigris.co/](http://verdigris.co/) for commercial/industrial
applications.

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joezydeco
Your meter may already have a Zigbee interface built into it. Check with your
utility company.

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jwatte
As the pedant will note, neither Newton nor Heisenberg actually allow "non-
invasive" power monitors. Your current sense transformer will draw some minute
amount of power :-)

Separately, you might be able to use a second transformer clamp to trickle
charge a supercap and not need batteries at all?

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tzs
> As the pedant will note, neither Newton nor Heisenberg actually allow "non-
> invasive" power monitors.

Assuming one is not using superconducting power cables, the wire should heat
up due to resistive heating, and the rate of heating should depend on the
current.

Couldn't we non-intrusively monitor this heating via IR, and from this infer
the power usage?

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db48x
Resistive losses in a wire are pretty low, unless the wire is too small. Then
the wire melts.

