On Sun, 17 Jun 2012 06:41:55 -0700 (PDT), " firstname.lastname@example.org"
The thing I don't see is he DPDT switch necessary to put both sides on
the same phase ... as if you could really do that.
I only have to point at multiwire circuits in the house so see the
folly of that., The idea that the main breaker would protect the SE
cable is silly too. It is going to be 2 breakers in parallel when you
put one phase down 2 paths.
All of this talk has me wanting to cut the seal, pull my meter and
look under the bottom to see if there is a "relay cover" as described
in the link Keating put up.
On Jun 17, 7:51 pm, " email@example.com"
Because disabling the 240V would affect only the AC, water heater,
stove, dryer, etc. and leave the 120V loads on. It would shed what
are usually the largest loads and also not the most critical. You
could kill those for say 15 mins at a time while leaving all the 120V
If you just set the limit at some limit, say 40 amps, when you go
above that, all the meter could do would be to turn off all the
to the whole house. An obviously better strategy, though more
difficult to implement would be to have the big loads be smart too.
That way they could selectively turn them off, in some priority
order. It could even be set so the homeowner decides the order,
ie water heater first, etc.
On Jun 18, 10:19 am, " firstname.lastname@example.org"
It's not an issue of safety. It's an issue of what can the meter or
mothership then do? With the disabling 240V loads you shed the
loads which are also ones that you can more likely do without for 20
If you go over say a 40 amp limit, the meter calls the mothership.
then what? Short of calling the home to tell people to turn stuff
which I guess is an option assuming anyone is even home,
all they can do is kill the power to the whole house.
On 6/18/2012 8:25 AM, email@example.com wrote:
Keating's link with the picture
has some interesting discussion of smart meters. Including the meter may
talk to the thermostat without calling the mothership.
Would be nice to see a good story on smart meters.
On 6/18/2012 10:10 AM, firstname.lastname@example.org wrote:
Can't remember if it in the link or a news article, but Honeywell is
supposed to have thermostats and "relay modules" that can be actuated by
smart meters. Time-of-day pricing can be a major incentive to do load
shedding (as it is with "demand" metering). For years there has been a
program here (and I presume a lot of places) where the utility can
trigger (I assume RF) a 'module' that shuts down A/C compressors for a
short time. In exchange, fixed electric rates are significantly lower.
Maybe we will wind up with refrigerators talking to electric meters to
order milk when we are getting low. And maybe the electric meters will
run on Windows 13.
Everything on single-phasing is based on slightly more than nothing in a
meter description that does not explain how the feature (if it actually
exists) would be used. IMHO multiwire neutrals are a bigger problem than
service neutrals. But it is all complete speculation with no reason to
believe anyone has even vague thoughts of shedding by single-phasing.
Our electric utility, Dominion, in east central Virginia offered us a
"discount" if we permitted them to insert a relay (controlled by their
"box") in the heat pump compression "demand call" circuit.
I don't remember the exact number but the "savings" to us were trivial
(certainly less than $10/month). I figure extra and un-necessary
switching of the compressor will add a lot more than $120/year in wear &
tear. (If you don't believe me, call up you HVAC guy and ask how much
it would cost to replace the compressor.)
Before we owned this property, the utility had some "modules" that could
turn off the water heater when commanded. It had all been disconnected
when we got the place. I salvaged some really rugged plastic boxes
(about half the size of shoe boxes) which, I suppose, I will find a use
for some day.
Water heater control is really, really silly. There just isn't any
guarantee that switching off a particular WH will save any power.
It would be interesting to find out just how much "spinning reserve"
actually costs the utility.
Sometimes significant load shedding is called for. When it is, $.05 &
$.10 stuff like turning off the heat pump compressors for 10 minutes out
of any hour will not do the job. The only answer is to "pull the plug"
on entire towns or major portions of big cities. When that happens the
"people" are put on notice that the next time the power company wants to
build a new plant or install a new transmission line to not play NIMBY.
Let me jump in here.
Odds are that most shared neutral circuits found in the kitchen
typically only have one significant load running at any particular time.
The big loads are stand alone microwave, toasters, and "toaster
ovens." Everything else is down in the noise.
Maybe so; maybe no.
We don't have any shared neutral circuits in the first place.
Even if we had completely current wiring, the microwave would have its
It would take me the better part of an hour even to FIND the hot plates
(we use them occasionally to keep food hot on the table.)
If we are talking about your "typical" consumer, it would take him the
better part of an hour to convince himself the stove isn't working.
(The light and "electronics" run on 120 volts.)
Oh, it's completely impractical. It would take a VERY good sized
"contacter" to switch over a 100 or 200 amp service.
How much it costs to replace a compressor isn't the issue.
How much more cycling do you really think a utility is going
to do with an AC? I have the RF system on my AC and the
electric company activates it in emergency situations
maybe 3 times a year. Even if they activate it
30 times a year, compare that to how many times the AC
or heat pump cycles already on it's own and it's negligible
in adversely affecting the system life.
The purpose isn't to save power. It's to reduce peak demand
during critical times. A water heater is probably the BEST example
of where that makes sense. Like the last few days when AC
usage has pushed demand to peaks. Turning off the water heaters
from say 2PM to 6PM could save the utility and all it's customers
from having to pay primo prices for extra power. Or it could
avoid having brownouts or complete power loss.
According to you. Power companies, who should actually know,
have a very different opinion.
Whether any house in particular has or doesn't have a shared
neutral circuit isn't the issue. The issue is that they exist and
are code compliant. It was suggested that smart meters shed
240V loads when needed by temporarily connecting both
house hots to one incoming hot. If they did that, any house
with an edison circuit would have the potential to overload
the shared neutral inside the house by 2X. And there is no
easy way to know how any house is or isn't wired.
It's already been demonstrated that smart meters do
exist that can turn the power on and off. Folks have posted
On Jun 19, 12:47 am, " email@example.com"
And I thought the issue was that it was alleged that smart
meters can shed load temporarily if the utility needs to do so during
a peak emergency. From earlier in the thread where discussion
about this feature started:
"to answer the original question,"smart meters" are electric meters
homes that monitor your power usage continuously and keep record of
much power is used at what times of the day and night,periodically
remotely by the power company.
they may also have the capability to remotely CONTROL(shut off) some
your home's appliances to aid the power company in load managment.
You may not like the power company turning off your AC,water
washer-dryer at peak demand times. "
Connecting both house hots lines to
one incoming would achieve that by cutting off power to
the 240V appliances, ie the ones that use the most power,
but are less critical than the lights. We agree that while
this would achieve the above objective, it has serious
issues that make it unfeasible.
Around here, NJ, if you don't pay your bill, they don't
disable your 240V stuff. They just turn off the electricity
On Sun, 17 Jun 2012 06:41:55 -0700 (PDT), " firstname.lastname@example.org"
If you ever looked at the meters (or watched them being installed), when they're
installed in the meter socket, one quickly realises the "meter base" is part of
Pair of single phase meter sockets...
Typical sideways view of 3 phase meter..
Bottom view of single phase service meter with ground lead attached..
email@example.com (Gordon Burditt) wrote in
"more EQUITABLY"? how is that "more equal",charging different rates for
different times of the day?
IMO,that is just a revenue scam. Generates more money and discourages
people from running AC or heavy appliances at certain times.
I already have a meter that is remotely read.
but it's only read once a month,and doesn't keep track of WHEN I'm using
it's not that many utilities need to build more capacity,it's that Comrade
Obama is forcing many coal plants to shut down. It's part of his attack on
the US economy,punishing the "evil wealthy America" by lowering our
standard of living.
Just look at the big picture. connect the dots.
I can't speak for the meter you have but FPL is installing the GE 210+
It is just an electronic meter, no "cut off" hardware or anything else
This meter feeds a low power RF device inside the meter that
communicates with a transmitter on the pole and from there it relays
the info to the utility in real time.
Silver Spring NIC 314
The meter seems to be capable of transmitting a couple hundred yards
based on the distribution of the pole mounted access units.
On Sat, 26 May 2012 14:04:18 -0400, firstname.lastname@example.org wrote:
(they also relay data from meter to meter.)
As for remote disconnect, I see you haven't done your homework..
I called up GE and talked to an engineer about the various
undocumented ordering options, some of ordering designations for the
GE I-210+ are,
O = AMR,
V2 = Simple Voltage event monitor,
F2 = Demand limit,
J2 = Emergency Load reduction(same leg of 110V connected to both
sides, no"0v appliance operation.)
U2 = Remote disconnect & Prepaid disconnect.
Now go outside and check the installed options on your smart electric
As I read the datasheet the 210+ has both as optional capabilities; I
don't follow your above conclusion it's "just" an electronic meter
(altho FPL may not have ordered the option is what you're confirming,
As say, for any specific install checking the codes on the meters is the
way to know what is actually there...of course there still can be more
capability available than a utility is using (or may ever use).
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