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[BLU/Discuss] Kill-a-watt devices

Hi everyone,
my local electric company has what they call "test metering equipment"
for appliances.  I went down to their offices last week and borrowed
one of these devices.  Imagine my surprise when they passed over the
counter to me, an actual power meter, mounted on a nice gray utility
box that was bolted to a fairly thick chunk of metal with giant rubber
feet on it and to thick black electrical cords hanging off with it.
Altogether it weighs about 25 pounds.

>From the front, the circular glass dome and funny dials and numbers,
with the floppy black appendages hanging off of it in almost resembles
the flying spaghetti monster.

I was a little shocked, :-) but I cradled the awkward, (it's about 18
inches high by six inches wide by three inches deep not including the
glass dome or the metal plate on the bottom with the dangling floppy
appendages), to my chest and lugged it out to the car.

This meter is a little easier to read than the old-fashioned once with
the series of rotating pointers, which alternate their direction of
rotation as you go from pointer dial to pointer dial.  While this one
has the ubiquitous spinning disk deep down in its innards, the kilowatt
hours consumed are displayed on a series of cylinders which have digits
printed on them.  The cylinders are mounted vertically and at some time,
as you consume more electricity they rotate counterclockwise.  Imagine a
miniature 55 gallon drum, standing on end with numbers painted around
it facing a small window that you can see one number at a time through
the window.

So this gadget has no way to display any unit smaller than 1 kilowatt
hour and, because the display is sort of an analog device, figuring
out exactly when 1 kilowatt hour has been consumed is a little bit of
a challenge.  Even more so because the digits are not centered exactly
in their windows when they come to a stop between movements.

It seems to me that this gadget has a built-in read error factor based
on how it displays the information.  I have no way of knowing how much
of the A. kilowatt hour has been produced at anytime between changes of
the final digit.  Right now I've been using it to measure a laptop, so
far the laptop has been running for 83 hours without consuming a single
kilowatt hour.  For all I know we could roll over to that full kilowatt
hour at any second or it could take another four days to get their.

Does anyone know if the Kill-a-watt devices are able to measure
consumption in smaller units than a single kilowatt hour?

Any suggestions on better ways to do this?
I have to assume the time it took to machine the metal and assemble the
whole unit cost them more in time then buying a kill-a-watt meter

Thanks, Jeff
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