DComTalk.com

With very low channel width and appropriate signalling you do not need
to bridge transformers. However if complex tariffs are envisaged
there may be a need for transmitting up to 24 readings a day per meter
and this may be beyond such systems.

In Germany they send around control signals to turn on "night storage
heaters". Basically a huge block of bricks that is heated up off-peak
and then a fan kicks out the stored heat during the day.

In article <i4uf01doft60n1f23rt4ep34kf7b8o5d6u@4ax.com>,
Jim Thompson <thegreatone@example.com> wrote:
[...]
(1) RF transmitter at your meter, "neighborhood" receiver located on a
pole, then connection to phone lines.

(2) Modem connection between your meter and *your* phone line. Power
company polls your modem.

I'll add:

(3) An RF responder that is pinged from a truck going down the street.


I know, some places use this for water meters, but I expect that someone
has done it for power meters.

It seems interesting that none of these technologies has made

Ferinstance, an ancient Diablo 630 printer has such a good noise filter
that it takes out any X-10 device within 200 feet.

--
Many thanks,

In misc.industry.utilities.electric John <john_t@no.spam> wrote:
| Don Lancaster wrote:
|
|> I guess I was involved in the earliest of powerline carrier
|> communications. Back in 1961 at Femco.
|
|> It did not work then and it will not work now.
|
|> Ferinstance, an ancient Diablo 630 printer has such a good noise filter
|> that it takes out any X-10 device within 200 feet.
|
| Powerline communications doesn't work in the 21st century? Really? Gosh
| somebody forgot to tell these people:
| http://www.powerlinecommunications.net/ ... erline.htm
|
| PPL has had running broadband Internet over powerline services in select
| markets for a few years now. Some other utilties have similar programs.
| http://www.thestreet.com/_tsclsii/tech/ ... 45487.html
|
| Utilities not only have another revenue stream and an efficient Internet
| distribution method, but also gain the benefit of a communications channel
| to/from their meters.
|
| The ARRL (amateur radio group) has spoken out against some powerline
| communications, out of fears that it will cause interference to them.

Hams continue to speak out well after BPL is operating. The interference
is documented. Further, BPL is, itself, ruined by nearby transmitters.

Although any wire infrastructure can carry data, it does have limits based
on many factors. And power lines are not designed for high data rates.
They are unshielded, and as a result are susceptible to interference, and
radiate their own interference. Phone lines also have documented problems,
but at least they are twisted. The only part of the power lines that are
twisted are the triplex overhead drops.

BPL is going to be very limited in top speed. As bandwidth goes up, so goes
the sensitivity to noise and interference. Things like electronic ballasts
operating between 20 kHz and 50 kHz are going to be another interference
source.

The power companies are just playing a "me, too" game on this. They wanted
in on the "riches" the internet was bringing to telephone and cable companies.
But as the bandwidth demands of the market top 100 mbps, power companies are
going to be playing the tune "where'd they go?".

It's a bad investment for
the power companies. Right now, I wouldn't put any money in their stock.

Maybe where you live. Here the gas company reads the meter electronically
via radio as they drive down the street and similar story for the electricity
company.

You forget that the power utilities aren't setting out to do this to
become Internet companies, they were looking for efficient ways to
communicate with their meters (and utility controlled thermostats).

Being able to offer and sell Internet broadband access is a nice side
effect of having the infrastructure.