Re: Digital Tools Help Users Save Energy, Study Finds

["Robert Green" <ROBERT_GREEN1963@xxxxxxxxx>]

"Dave Houston" <nobody@xxxxxxxxxxxx> wrote in message
news:478c8bb9.374342328@xxxxxxxxxxxxxxxx
> "Robert Green" <ROBERT_GREEN1963@xxxxxxxxx> wrote:
>
> >Sounds interesting.  Since Allelectronics has some sort of Hall effect
> >sensor for 50 cents each, I just ordered a few.  I wonder if the Ocelot
will
> >be able to read them directly or whether I need some additional drive
> >circuitry?  Have you seen any sample circuit designs?
> >
>
>http://www.allelectronics.com/cgi-bin/item/SS-19T/search/HALL-EFFECT_MAGNET
I
> >C_POSITION_SENSOR_.html
>
> You'll need the specific current sensing sensors which are not the same as
> the things you've bought. Allegro has example circuits. These range from
> SOIC-8 chips to much larger devices. Google on "Allegro current sensor" or
> just follow the crumbs to...

Oh well.  For $1 I got some components to practice my SMD soldering
techniques on.  I suspect these sensors are very much like the tiny ones in
three-wire CPU and PC case fans that detect revolutions.  In looking
further, it doesn't seem that there's going to be any way to add power
monitoring that's even remotely codeworthy.

>
http://www.allegromicro.com/en/Products/Categories/Sensors/currentsensor.asp

There also appear to be issues with current ranges and sensitivity at the
low end not being quite good enough.

The solution appears to be on its way from the power company, though, with a
smart meter that can report near-real time use to both me and the company.
The utilities also have a large incentive to move to real-time metering.
It's a lot harder to steal power if the utility can detect abnormalities on
a real-time basis.

Still, I am going to hook the Hall-effect sensors to some wire to see what
they read when deployed next to one of the 240VAC feeds and connected to a
power supply and a digital multimeter.

--
Bobby G.