> I'm not an EE, but I believe they are measuring the drop across shunt
> (the .001 ohm resistor. Using that, and knowing what the voltage
> supplied is (line voltage is a standard), you can calculate wattage. My
> guess is that this circuit would need changing for use in Europe
> (Circuit Cellar being an American publication I believe).

        Unfortunately that is not, by itself enough, you also must measure the
phase difference between the V and I waveforms. The reason is power factor.
If you just multiply V and I of an AC power system you get VA, power is
VA*pf (pf = power factor). TTYL

--
http://www.piclist.com hint: To leave the PICList
mailto:piclist-unsubscribe-request@mitvma.mit.edu