In message , at 07:44:36 on Wed, 18
Mar 2015, john james remarked:

"Roland Perry" wrote in message
...
In message , at 05:36:18 on Wed, 18
Mar 2015, john james remarked:
I'd expect to be taking perhaps 100 measurements of the house,

Smart meters don't provide samples of the current consumption
of the house, they integrate the total current consumption and
report that at a few instances a day.

To do that they need to take lots of readings - rather than classic
analogue meters which inherently do the integration.

Yes, but those readings never leave the smart meter.

Today.

How often they send those individual readings back to base will
depend on how much they need to know.

But it is never going to be feasible to send say the integral
every 4 seconds, there is nowhere near the comms bandwidth
available to do that.

Today.

These metering schemes are advertised as capable of telling the
householder how much power each of his appliances takes - so that the
householder can make decisions about buying more economical examples
of each one, or perhaps arrange that they are only powered-up off-peak.

Yes, but that data doesn't need to leave the house.

So you agree the meter can work out which appliances are drawing what,
including two different TVs?

If
the local meter is doing that - they can send the answers back to
base too.

But not anything like the data rate necessary to allow a central system
to compare the waveform with what you get when you compare it with
the screen intensity and contrast levels with TV program content even
with one TV, let alone more than one.

See my previous comments about the reverse-analogy you are pointedly
ignoring.
--
Roland Perry