[Nut-upsuser] Newbie question: real-time power usage monitoring?

James Cameron quozl at us.netrek.org
Wed Oct 19 21:49:50 UTC 2011

On Wed, Oct 19, 2011 at 08:40:40AM -0400, Christian Convey wrote:
> You're right - I *am* looking for total energy expenditure (Joules,
> Watt-hours, etc.)  I have no specific desire to do that integration in
> my own code.

What I used was a kit design from Silicon Chip in 2004, one retailer
provides this as
but there are others.

It is significantly more expensive than the consumer watt hour meters
available today.

It contains a chip that accumulates the counts independently, and
a microcontroller driving the display and panel buttons.

If I was doing what you are doing, I would replace the microcontroller
with one that relays the readings over USB, serial, or ethernet.  Then
I'd worry about high voltage isolation and chuck in an optoisolator.

I imagine there are better designs for the job.  I'm only sharing my
limited knowledge of the subject.  ;-}

Your later point about having the device do the counting and then seeing
timed results reminds me of my very early work on the same subject ... a
rotation sensor that emitted a millisecond counter alongside a rotation
counter, so that it didn't matter when the host computer processed the


James Cameron

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