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watt-hour meter

Discussion in 'Electrical Engineering' started by Sawney Beane, Nov 21, 2005.

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  1. Sawney Beane

    Sawney Beane Guest

    For years I have used the watt-hour meter at the service entrance to
    measure the rate of power consumption. I'd switch off all circuits
    except a known load, such as incandescent bulbs or a water heater, then
    time the on the meter disk to determine the constant in the relationship
    between speed and watts.

    Turning everything off requires resetting digital devices. If a year
    later I wanted to check wattage and couldn't remember the constant, I'd
    have to go through the procedure again. I couldn't be certain that my
    test load was using exactly the watts I thought, and a constant found
    for one watt-hour meter wouldn't necessarily apply to another.

    Today I read that on most meters, Kh is the watt-hours per revolution.
    (I wonder what Kh stands for.) Aha! You read the Kh, multiply by 3600,
    and divide that constant by the seconds per revolution to get watts.

    My Kh is marked 7.2. The time for 1/10 revolution was 41 seconds. That
    came out to 63 Watts, right?

    The house was running a computer in sleep mode, hooked up to an external
    drive, an external modem, and a boom box. I switched that all off,
    leaving only the power supply for the computer clock. There was a night
    light. I switched it off. Otherwise, there was standby power for
    various digital items: microwave, tv, vcr, radio, answering machine, and
    furnace controller.

    I timed the disk. Still 41 seconds. How could turning off my computer
    equipment and the night light not have reduced power consumption? I
    went out and timed it again. Still 41.

    The third time, it had slowed way down. I don't know of anything in the
    house that would have switched off since my last check.

    Over the years I've seen that with other watt-hour meters. When a load
    is turned on, there can be a long pause before the disk suddenly speeds
    up. When the load is reduced nearly to zero, the disk may continue
    spinning, then suddenly come nearly to a stop. What could account for
    these delays in electromechanical watt-hour meters?
     
  2. It is not really happening. The response of a watt-hour meter to changing
    load is instantaneous (OK, there is a finite delay, but you won't measure it
    with the naked eye).

    Most watt-hour meter test equipment tests the meter by applying a known load
    and measuring the time for the disk to rotate.....one time! If the meter
    paused long enough for you to see it, it would fail the test.

    The disk does not pause. You are seeing some other loads cycling. You used
    to be able to buy a desk lamp with a watt-hour meter and an incandescent
    light bulb. Turn on the bulb, meter spins immediately, turn off the bulb,
    meter stops. No pause.



    Charles Perry P.E.
     
  3. daestrom

    daestrom Guest

    Like Charles said, your typical watt-hour meter doesn't have such a delay.
    The inertia of the disk is so small that for all intents and purposes, they
    respond instantly to load changes.

    Have you looked for some other cycling load? Perhaps a refrigerator?

    daestrom
     
  4. Sawney Beane

    Sawney Beane Guest

    I was sure it wasn't the refrigerator. Yesterday I had time to
    investigate further. I discovered a possibility: the air conditioner.
    It has a heater for the outside unit. I wonder: is there any harm in
    leaving it off for the winter? How long should it be allowed to warm up
    before I run the compressor next summer?

    With only three breakers on, I got 135 Watts. Oh-oh, I'd left a
    fluorescent on in the bedroom, estimated at 100 Watts. I turned it off
    and got 35 Watts. I went through the house looking for circuits that
    were energized. All that seemed to be on were voltages for chips in the
    answering machine, the microwave, and the furnace. I unplugged the
    answering machine and the microwave. The meter disk didn't move in
    several minutes. I plugged them back in. The disk still didn't move in
    several minutes.

    I guess those three devices didn't provide enough torque to get the disk
    moving. So far I haven't seen it move slower than 35 Watts, and I
    haven't been able to account for more than an estimated 15 watts.
     
  5. Don Kelly

    Don Kelly Guest

    Your furnace likely has a small transformer to step down to supply the
    thermostat and control relay. You also have a small transformer for your
    doorbell. These are both cheap units -lossy at no load- and if you have an
    electronic thermostat, there will be some more losses. This will chew up
    some of your 15 watts. Did you unplug any electric clocks, etc?
    Try opening your main breaker - shutting everything off- and see what
    happens. --

    Don Kelly @shawcross.ca
    remove the X to answer
    ----------------------------
     
  6. daestrom

    daestrom Guest

    The crankcase heater is important to prevent the refrigerant from dissolving
    into the oil. If it does, when you start the unit the oil will foam up and
    damage the compressor. I turn off the breaker in the fall each year and
    turn it on at least 24 hours before running the unit. (Crane manual says
    six hours, but what the heck...)

    daestrom
     
  7. Sawney Beane

    Sawney Beane Guest

    My only outlet-powered clocks are in the range, microwave, computer, and
    answering machine. The range breaker was off. I didn't try the
    doorbell to see if it was on a live circuit. The thermostat is
    mechanical, but the board in the furnace is digital.

    The wheel could stop with the furnace, answering machine, microwave, and
    perhaps doorbell energized, or it could indicate 35 Watts, apparently
    with no additional load. I was unable to get it to turn between 0 and
    35 Watts by disconnecting those small loads one by one.

    If I knew more about shaded-pole motors, it might make sense to me.
     
  8. ehsjr

    ehsjr Guest

    Sawney Beane wrote:
    <snip>

    Shouting ...
    SHUT OFF THE MAIN BREAKER, AS DON KELLY SAID.

    Then report your findings. What you *think* is connected,
    and what is *actually* connected may differ. If the meter
    does not stop with the main off, you have a serious
    problem. The proper procdeure for shutting off the
    main is to first shut off all the other breakers, then
    the main. When restoring power, turn the main on first,
    then all the other breakers, one at a time.

    For branch circuit testing to find out which circuit is causing
    the meter to run: (Shouting)
    TO DISCONNECT LOADS THAT MAY BE MAKING YOUR METER RUN, SHUT OFF
    THE BRANCH CIRCUIT BREAKERS.

    Then report your findings. Unplugging some stuff and leaving
    other stuff plugged in tells you precisely ... nothing. You end
    up not knowing which "stuff" on which branch causes the meter to
    run. Do it right and you'll get it right.
    Ed
     
  9. Sawney Beane

    Sawney Beane Guest

    MAY I SHOUT, TOO?

    I SHUT OFF THE MAIN SEVERAL DAYS AGO. NATURALLY, THE METER STOPPED.

    AS I SAID, MY METER WILL ALSO STOP WHILE SUPPLYING POWER TO THE DC
    SUPPLIES OF AT LEAST THREE HOUSEHOLD DEVICES.
    AS I SAID, THE ONLY BRANCHES I RUN ARE THE ONES WITH THE THREE DEVICES
    WHOSE COMBINED WATTAGE WON'T NECESSARILY TURN THE METER. SHOUTING IT
    MAKES ME FEEL THAT I KNOW EVERYTHING THERE IS TO KNOW!
    WATT WILL I GET RIGHT? WATT'S THE SMALLEST WHATAGE YOUR METER WILL REGISTER?
     
  10. ehsjr

    ehsjr Guest

    Of course.
    But you never told us that. So your shouting it now is unjustified.
    But the information is welcomed.
    No, you didn't. You said the meter did not turn after you
    plugged them back in:
    "All that seemed to be on were voltages for chips in the
    answering machine, the microwave, and the furnace. I unplugged the
    answering machine and the microwave. The meter disk didn't move in
    several minutes. I plugged them back in. The disk still didn't move in
    several minutes.

    I guess those three devices didn't provide enough torque to get the disk
    moving. So far I haven't seen it move slower than 35 Watts, and I
    haven't been able to account for more than an estimated 15 watts."

    So again, your shouting is not justified.

    Since the distinction between unplugging something that had been
    operating vs stopping the meter *by* unplugging escapes you:
    A device can draw power periodically and store it, stay operational
    off the stored energy for a period while not drawing any more, and
    then draw it again when the stored energy level needs to be
    replenished. Whether that is happening with your answering machine
    and microwave I cannot say - but the possibility exists. Your
    devices may have stored power while they were connected, and may
    not have used it up in the several minutes they were disconnected
    and the several minutes you monitored the meter after connecting them.
    That's the problem. You've adopted an approach and asked
    for help, but then resisted the answers.
    What will you get right is the answer to your mystery.
    Part of what puzzled you was why the meter was running when
    you thought it shouldn't. (It seems that part may be solved
    in your mind.) And part of what puzzles you is why the meter
    doesn't move when you think it should.

    Finally, I apologize for shouting - not because I shouted,
    but because it apparently did not have the desired effect.
    It was for emphasis, to try to get you to think about the
    answers, rather than resisting them. All I see is that it
    made you angry - not the intended effect.

    Good luck with your mystery.
    Ed
     
  11. Pop

    Pop Guest

    ....
    : "All that seemed to be on were voltages for chips in the
    : answering machine, the microwave, and the furnace. I unplugged
    the
    : answering machine and the microwave. The meter disk didn't
    move in
    : several minutes. I plugged them back in. The disk still
    didn't move in
    : several minutes.
    :
    : I guess those three devices didn't provide enough torque to get
    the disk
    : moving. So far I haven't seen it move slower than 35 Watts,
    and I
    : haven't been able to account for more than an estimated 15
    watts."
    ....

    Jeez, guys: a nightlight and such isn't going to show any meter
    movement for a LONG time; probably days, certainly many hours!
    Think about it! Certainly you won't see anything in 'several
    minutes' as mentioned here! Oh, and the wheel will most likely
    turn - done it with vacation home with night lights; 3 of them;
    left on for a winter.
     
  12. daestrom

    daestrom Guest

    Well, a 7 watt nightlight on a meter with a Kh=7.2, should rotate the disk
    once in just under an hour. But I think there is a minimum friction where
    it just won't register. I think it was Charles that had a link to
    watt-hour-meter calibration spec.

    Utility has to answer to the state's public service commission if too many
    of their meters register with *no* load, while if they don't register with a
    tiny load, they don't stand to lose very much (most utilities have a
    flat-rate for the first few kwh just for having service, so they get paid
    for those kwh even if the meter doesn't register them). So it wouldn't
    surprise me if there is a minimum load before the mechanical ones actually
    start to turn.

    Wonder if the new electronic style are better? Seems an electronic
    integrator setup could probably be more accurate at tiny loads.

    daestrom
     
  13. Pop

    Pop Guest

    :
    : : > ...
    : > : "All that seemed to be on were voltages for chips in the
    : > : answering machine, the microwave, and the furnace. I
    unplugged
    : > the
    : > : answering machine and the microwave. The meter disk didn't
    : > move in
    : > : several minutes. I plugged them back in. The disk still
    : > didn't move in
    : > : several minutes.
    : > :
    : > : I guess those three devices didn't provide enough torque to
    get
    : > the disk
    : > : moving. So far I haven't seen it move slower than 35
    Watts,
    : > and I
    : > : haven't been able to account for more than an estimated 15
    : > watts."
    : > ...
    : >
    : > Jeez, guys: a nightlight and such isn't going to show any
    meter
    : > movement for a LONG time; probably days, certainly many
    hours!
    : > Think about it! Certainly you won't see anything in 'several
    : > minutes' as mentioned here! Oh, and the wheel will most
    likely
    : > turn - done it with vacation home with night lights; 3 of
    them;
    : > left on for a winter.
    : >
    :
    : Well, a 7 watt nightlight on a meter with a Kh=7.2, should
    rotate the disk
    : once in just under an hour. But I think there is a minimum
    friction where
    : it just won't register. I think it was Charles that had a link
    to
    : watt-hour-meter calibration spec.

    Yeah, there does have to be a minimum friction, I'd have to
    agree. I guess I was reacting more to waiting a "few minutes" or
    whatever the phrase was.
    Also, everyone here says, and others seem to agree with, the
    fact that 1 revoution = 1 kWH but that's not true here in upstate
    NY. I don't recall the numbers anymore, but when I was using the
    spinning disk to measure power, my utility told me where to find
    the "multiplier" on the meter face to convert the number of
    revs/minute to kWH. I don't recall the number any longer, but
    two numbers are stuck in my head: 6.4 and 7.2. I do know the
    disk didn't indicate that one rev was a kWH though; it was far
    from it.
    They recently stuck us with one of the modem call-home types
    so I can't support my allegations anymore. I really dislike the
    new digital meters: There is zero way to guestimate ANY power
    usage unless it's a very high current or a long period of time.
    The lowest digit is a kWH; you'd think they'd have been down to
    tenths, at least, but I guess since they charge by even hours,
    they only have to display the even hour.
    Oh! A little sidelight here: When they went down the road
    here switching out the meters for the new digitals, you should
    have heard the complaining about the power company using THEIR
    phone lines to call in their meter readings, and how could they
    stop it, and what else was it telling them about their houses?
    <G>. They just couldn't fathom that it didn't use the phone
    lines for that.
    :
    : Utility has to answer to the state's public service commission
    if too many
    : of their meters register with *no* load, while if they don't
    register with a
    : tiny load, they don't stand to lose very much (most utilities
    have a
    : flat-rate for the first few kwh just for having service, so
    they get paid
    : for those kwh even if the meter doesn't register them). So it
    wouldn't
    : surprise me if there is a minimum load before the mechanical
    ones actually
    : start to turn.
    :
    : Wonder if the new electronic style are better? Seems an
    electronic
    : integrator setup could probably be more accurate at tiny loads.

    Interesting: I'll bet the new digitals don't have any trouble
    seeing six or seven watts. I wonder ... oh well, not worth any
    time or I'd go see what I could find out <g>. Reminds me of the
    big scandals when the banks were caught rounding less than penny
    billing fields to their favor. e.g. if you owed $100.032, you
    got charged $100.04. And vice versa.

    : daestrom
    :
    :

    Cheers,

    Pop
     
  14. Sawney Beane

    Sawney Beane Guest

    Do you remember when he posted it?
    Did anyone in this thread say 1 revolution = 1 kWh? For decades, if
    I wanted to use a watt-hour meter to measure watts, I had to time
    the disk with a known load. At the start of this thread I said I'd
    just learned where the watt-hours per revolution is printed on a
    meter.
    My disk turns 1000 times faster than yours: 1 revolution is 7.2 Wh.
    My disk is divided into 100 marks. In 5 minutes, a 7.2W nightlight
    should move the disk 8.3 marks.
     
  15. Sawney Beane

    Sawney Beane Guest

    I've found information on watt-hour meters. Speed is proportional
    to power because magnets cause retarding torque proportional to
    speed. Those magnets are adjusted to calibrate the meter at its
    rated load, typically 30 A.

    Then they adjust some sort of compensation to calibrate it at 10% of
    its rated load. For me, that would be 720 W.

    When that's done, it will read high at less than 10%. At 1% of its
    rated load it may read 100% high. What do you know? All my
    troubles have been below 72 W!

    The disk has holes to stop it at very light loads. That way the
    customer won't see the disk keep turning after he turns off his main
    breaker, and the power company can keep claiming its meters are accurate.

    That explains my two most recent obsevations: that a load of about
    15 W reads 35, and that load won't start the disk moving.

    So if I want to use the power-company meter to see how much power a
    small device uses, I should first turn on several lights so the
    total will be in the 700 W range.
     
  16. Pop

    Pop Guest

    : Pop wrote:
    : >
    message
    : > : > :
    : > :
    : > : Well, a 7 watt nightlight on a meter with a Kh=7.2, should
    : > rotate the disk
    : > : once in just under an hour. But I think there is a minimum
    : > friction where
    : > : it just won't register. I think it was Charles that had a
    link
    : > to
    : > : watt-hour-meter calibration spec.
    :
    : Do you remember when he posted it?
    : >
    : > Yeah, there does have to be a minimum friction, I'd have to
    : > agree. I guess I was reacting more to waiting a "few minutes"
    or
    : > whatever the phrase was.
    : > Also, everyone here says, and others seem to agree with,
    the
    : > fact that 1 revoution = 1 kWH
    :
    : Did anyone in this thread say 1 revolution = 1 kWh? For
    decades, if
    : I wanted to use a watt-hour meter to measure watts, I had to
    time
    : the disk with a known load. At the start of this thread I said
    I'd
    : just learned where the watt-hours per revolution is printed on
    a
    : meter.
    :
    : > but that's not true here in upstate
    : > NY. I don't recall the numbers anymore, but when I was using
    the
    : > spinning disk to measure power, my utility told me where to
    find
    : > the "multiplier" on the meter face to convert the number of
    : > revs/minute to kWH. I don't recall the number any longer,
    but
    : > two numbers are stuck in my head: 6.4 and 7.2. I do know
    the
    : > disk didn't indicate that one rev was a kWH though; it was
    far
    : > from it.
    :
    : My disk turns 1000 times faster than yours: 1 revolution is 7.2
    Wh.
    : My disk is divided into 100 marks. In 5 minutes, a 7.2W
    nightlight
    : should move the disk 8.3 marks.

    Interesting; and informative. Thanks for the education.
     
  17. Pop

    Pop Guest

    : daestrom wrote:
    : >
    : >
    : > Utility has to answer to the state's public service
    commission if too many
    : > of their meters register with *no* load, while if they don't
    register with a
    : > tiny load, they don't stand to lose very much (most utilities
    have a
    : > flat-rate for the first few kwh just for having service, so
    they get paid
    : > for those kwh even if the meter doesn't register them). So
    it wouldn't
    : > surprise me if there is a minimum load before the mechanical
    ones actually
    : > start to turn.
    : >
    :
    : I've found information on watt-hour meters. Speed is
    proportional
    : to power because magnets cause retarding torque proportional to
    : speed. Those magnets are adjusted to calibrate the meter at
    its
    : rated load, typically 30 A.
    :
    : Then they adjust some sort of compensation to calibrate it at
    10% of
    : its rated load. For me, that would be 720 W.
    :
    : When that's done, it will read high at less than 10%. At 1% of
    its
    : rated load it may read 100% high. What do you know? All my
    : troubles have been below 72 W!
    :
    : The disk has holes to stop it at very light loads. That way
    the
    : customer won't see the disk keep turning after he turns off his
    main
    : breaker, and the power company can keep claiming its meters are
    accurate.
    :
    : That explains my two most recent obsevations: that a load of
    about
    : 15 W reads 35, and that load won't start the disk moving.
    :
    : So if I want to use the power-company meter to see how much
    power a
    : small device uses, I should first turn on several lights so the
    : total will be in the 700 W range.

    Interesting: Did you find that online and can you post a URL?

    Pop
     
  18. Sawney Beane

    Sawney Beane Guest

    Here's where I found the explanation of inaccuracies:

    http://www.totse.com/en/bad_ideas/scams_and_rip_offs/powrmetr.html

    Google took me there. I wasn't able to read about the second stage
    of calibration (at 10% load) because the text turned to gibberish as
    I scrolled.

    Here's a page that says GE Watthour meters have the disk mounted by
    magnetic suspension to avoid friction. (That wouldn't eliminate
    worm-gear friction.)
    http://www.ge.com/ph/indust_meter.htm

    Here's a 72-page manual on checking and calibrating watthour meters:
    http://www.usbr.gov/power/data/fist/fist3_10/vol3-10.pdf

    Adjusting braking magnets affects speed by the same percentage at
    all loads. When the magnets are adjusted to calibrate the meter at
    full load,friction would cause the meter to run slow at light loads.


    A short-circuited coil overcomes friction by increasing the effect
    of the field from the potential coil on the disk. Its position can
    be adjusted to adjust its effect. Its effect on disk speed is
    inversely proportional to the load, so the coil has the effect of
    adding a certain number of watts to the load.

    If my meter was calibrated with a light load of 750 W, maybe the
    torque adjustment to compensate for friction was equivalent to 20 W.
    At 15 W, it would take only 0.4 W to add that same torque. So my
    meter would read 34.6 W when the load was 15 W.

    Disk creep can be up to 1 revolution per ten minutes and still meet
    calibration standards. With a Kh of 7.2, that's 43.2 watts, or 1
    kWh/day.

    A disk has holes that serve as parking brakes. When a hole is
    directly under the pole of the potential coil, torque will be
    reduced. If the disk was moving very slowly, it may stop. With a
    very light load, the disk should be timed for a complete revolution
    because the holes will cause the speed to vary.

    That helps explain the lag I've noticed over the years. I used to
    live in a house where the meter and the breaker box were within
    arm's reach of the back door, so I could see the meter very quickly
    after switching breakers. If I switched everything off, the
    light-load coil would keep the disk turning until a hole came into
    position. If I switched on a 50-watt load, that might be just big
    enough to get the disk turning, but it might take a minute or so to
    move that first 1/4 of a mark, so that the hole was no longer
    interfering with torque.
     
  19. daestrom

    daestrom Guest

    Well, *I* didn't say it was 1kwh, and I see a couple of others that pointed
    out that the meter's Kh number tells you how many watt-hours per rev of the
    disk.
    Yep, the number you want is shown as Kh=xx (mine used to be 7.2 before it
    was replaced with a digital one).

    Here in upstate NY in Nimo(oops, National Grid) country, they've been moving
    to electronic meters. But the one I have has a small black 'dot' on the LCD
    readout that pulses with each watt-hour, to show you it's 'turning'.

    Look underneath the digital readout for a small LCD 'spot'. When you have
    some loads running, it should blink on/off slowly, the speed tells you how
    fast the older 'disk' would have turned.
    Funny, our meters (national grid in the CNY division) don't use phone lines.
    They are RF and the meter reader comes by once a month and simply drives
    up/down the street. His unit polls each meter and gets kwh reading and
    serial number while driving by at 10 mph. Still have a meter-reader, but
    one can cover the territory that used to take about eight.

    Are you *sure* yours uses a phone line? I know some commercial
    installations in DTE country (lower Michigan) required a dedicated phone
    line, but those were 'open choice' commercial customers, where the
    non-utility supplier had to schedule power in 15 minute intervals and bill
    accordingly.

    Who's your utility, maybe you can take the model no. off the meter and
    google it. That's what I did and found out all about it.

    daestrom
     
  20. Pop

    Pop Guest

    :
    : : >
    message
    : > : > :
    : > : : > : > ...
    : > : > : "All that seemed to be on were voltages for chips in
    the
    : > : > : answering machine, the microwave, and the furnace. I
    : > unplugged
    : > : > the
    : > : > : answering machine and the microwave. The meter disk
    didn't
    : > : > move in
    : > : > : several minutes. I plugged them back in. The disk
    still
    : > : > didn't move in
    : > : > : several minutes.
    : > : > :
    : > : > : I guess those three devices didn't provide enough
    torque to
    : > get
    : > : > the disk
    : > : > : moving. So far I haven't seen it move slower than 35
    : > Watts,
    : > : > and I
    : > : > : haven't been able to account for more than an estimated
    15
    : > : > watts."
    : > : > ...
    : > : >
    : > : > Jeez, guys: a nightlight and such isn't going to show
    any
    : > meter
    : > : > movement for a LONG time; probably days, certainly many
    : > hours!
    : > : > Think about it! Certainly you won't see anything in
    'several
    : > : > minutes' as mentioned here! Oh, and the wheel will most
    : > likely
    : > : > turn - done it with vacation home with night lights; 3 of
    : > them;
    : > : > left on for a winter.
    : > : >
    : > :
    : > : Well, a 7 watt nightlight on a meter with a Kh=7.2, should
    : > rotate the disk
    : > : once in just under an hour. But I think there is a minimum
    : > friction where
    : > : it just won't register. I think it was Charles that had a
    link
    : > to
    : > : watt-hour-meter calibration spec.
    : >
    : > Yeah, there does have to be a minimum friction, I'd have to
    : > agree. I guess I was reacting more to waiting a "few minutes"
    or
    : > whatever the phrase was.
    : > Also, everyone here says, and others seem to agree with,
    the
    : > fact that 1 revoution = 1 kWH but that's not true here in
    upstate
    : > NY.
    :
    : Well, *I* didn't say it was 1kwh, and I see a couple of others
    that pointed
    : out that the meter's Kh number tells you how many watt-hours
    per rev of the
    : disk.
    :
    : > I don't recall the numbers anymore, but when I was using the
    : > spinning disk to measure power, my utility told me where to
    find
    : > the "multiplier" on the meter face to convert the number of
    : > revs/minute to kWH. I don't recall the number any longer,
    but
    : > two numbers are stuck in my head: 6.4 and 7.2. I do know
    the
    : > disk didn't indicate that one rev was a kWH though; it was
    far
    : > from it.
    :
    : Yep, the number you want is shown as Kh=xx (mine used to be 7.2
    before it
    : was replaced with a digital one).
    :
    : > They recently stuck us with one of the modem call-home
    types
    : > so I can't support my allegations anymore. I really dislike
    the
    : > new digital meters: There is zero way to guestimate ANY
    power
    : > usage unless it's a very high current or a long period of
    time.
    :
    :
    : Here in upstate NY in Nimo(oops, National Grid) country,
    they've been moving
    : to electronic meters. But the one I have has a small black
    'dot' on the LCD
    : readout that pulses with each watt-hour, to show you it's
    'turning'.
    :
    : Look underneath the digital readout for a small LCD 'spot'.
    When you have
    : some loads running, it should blink on/off slowly, the speed
    tells you how
    : fast the older 'disk' would have turned.
    :
    : > The lowest digit is a kWH; you'd think they'd have been down
    to
    : > tenths, at least, but I guess since they charge by even
    hours,
    : > they only have to display the even hour.
    : > Oh! A little sidelight here: When they went down the
    road
    : > here switching out the meters for the new digitals, you
    should
    : > have heard the complaining about the power company using
    THEIR
    : > phone lines to call in their meter readings, and how could
    they
    : > stop it, and what else was it telling them about their
    houses?
    : > <G>. They just couldn't fathom that it didn't use the phone
    : > lines for that.
    :
    : Funny, our meters (national grid in the CNY division) don't use
    phone lines.
    : They are RF and the meter reader comes by once a month and
    simply drives
    : up/down the street. His unit polls each meter and gets kwh
    reading and
    : serial number while driving by at 10 mph. Still have a
    meter-reader, but
    : one can cover the territory that used to take about eight.
    :
    : Are you *sure* yours uses a phone line? I know some commercial
    : installations in DTE country (lower Michigan) required a
    dedicated phone
    : line, but those were 'open choice' commercial customers, where
    the
    : non-utility supplier had to schedule power in 15 minute
    intervals and bill
    : accordingly.
    :
    : Who's your utility, maybe you can take the model no. off the
    meter and
    : google it. That's what I did and found out all about it.
    :
    : daestrom
    :
    :
    No, ours doesn't use an actual phone line; sorry, didn't mean to
    imply that. I had my tongue in my cheek there about how everyone
    heard the "modem" word in an ad they left at each home, and
    everyone with a computer decided it was going to use THEIR phone
    lines. I was just commenting on the misconceptions of a couple
    people talking to others. The ad never said it used phone lines
    either, but clearly stated a "modem-like" device fed a small
    transmitter and gave the FCC registration no., etc.. I threw it
    away so I can't perfectly quote anything from it now.

    Never thought about using Google - good idea. Last time Nimo had
    all the info on the old meter online, but I can't find it again
    if it's still there. Google might be a good resource.
    I don't recall any opening under the readout, but I'll look
    next time I'm out there. You gave some good info - thanks!

    Regards,

    Pop
     
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