On 2015-06-15 20:47, James Knott wrote:
On 06/15/2015 02:13 PM, Carlos E. R. wrote:
The assumption is that they are power factor corrector boxes for homes.
Before you can correct, you have to know whether the load is overall capacitive or inductive and by how much
Or adjust automatically... I know that this can be done by switching power banks, or by electronic shapers. But these things are expensive.
The second assumption is that the home meters are imperfect, and measure rather current than actual wattage.
They measure power and must be accurate enough to be legal for trade.
Here they have been electromechanical for decades. A rotating disc, with coils. Something like this: http://www.gigahertz.es/images/contador-de-corriente-altena.jpg But they have been replacing them with electronics units that support remote reading from a data center, since about five years. I think there is a mandate to do all the country, perhaps all Europe, dunno. Mine is like this one: http://www.gigahertz.es/images/contador-inteligente-sagem-cx1000-6.jpg
On the other hand, the main purpose of those boxes might be to lighten your wallet. There have been a lot of scams over the years.
Yes, that's what I think myself, but I don't know. I can't tell my friends that they were victims of a scam without knowing what these things are, and I can't know unless I open one up... -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" at Telcontar)