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Home electricity meter

  1. Feb 8, 2010 #1
    I often see website ads for home electricity meters that check on home power usage in order to help save costs by monitoring what is used so homeowners can adjust their usage to cut costs.
    However, is there a much more sophisticated meter available that oversees actual home usage and compares that to the amounts utility companies state that we have used in our monthly bills? As far as I know, there has never been a convenient way to double check utility company charges and we have had to just pay the bill even if we thought/knew charges were excessive.
    It seems to me to be possible............by attaching the electricity meter to incoming leads before they get to the panel box thus before any usage. That would seem to help with those nagging doubts we all have about utility charges, and especially now that many utilities have gone to "Smart Meters" which have been seen to be suspect in that some customers with those installed say they think they are smarter for Big Utility than for the consumer.
    Confirmed accuracy would have to be well addressed and certified, as if not Big Utility could always say our home meters were innacurate and theirs were right so too bad, pay up or else.
    Informed and qualified answers and discussion are requested. Thank you all.
     
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  3. Feb 8, 2010 #2

    mgb_phys

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    You can check your bill by just writing down the number on the meter at the start and end of your billing period.
    You can test the meter by using one of the wall socket power meters together with a reasonably large appliance like a heater - remember to turn everything else off.

    The electricity company generally doesn't like you connecting anything before their meter. But they are usually very quick to respond to any problems with the meter - the fines for them using a miscalibrated meter are quite high, and they tend to lose in court.
     
  4. Feb 8, 2010 #3
    The public electric utility power meters measure only real power and not reactive power, so anyone measuring only amps and multiplying by volts will overestimate the power consumption. Typical reactive loads in residences include refrigerators, washing machines, etc.

    Bob S
     
  5. Feb 8, 2010 #4
    So, mgb and Bob S., you state limitations but no solutions. The new Smart meters make it difficult if not impossible for typical users to check usage. I ask, is that their real purpose?

    I think that we need a quality metering product on the home market that can be programmed to do all I stated earlier, and be certified accurate so it will be respected in court if usage disputes go that far.

    Hourly, daily, weekly, monthly monitoring all should be interactively displayed on a touchscreen....this should be easily accomplished with modern tech. (Where is Apple when we really need it?)

    It is high time for all of us to stop taking the word of powerful utilty supply companies that what they say to us is gospel and we should never question it.
     
  6. Feb 8, 2010 #5

    sophiecentaur

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    If you connect an electric heater and measure time, current and volts, the energy meter reading should agree with calculations using your VIt product. Also you could check that zero load produces no consumed units.
    I never had any suspicions about electricity bills but I did once have a problem with over volts (light bulbs used to last only a matter weeks).
    I hit the company with MIEE etc, in my letter and they sent a man round with a recording meter. The meter trace was clearly over the top but, when they retreived it, they denied it all, claiming that the volts were within spec. Strangely enough, however, the volts suddenly went down to something reasonable and bulbs stopped blowing.
    Make enough of a fuss and you may get a fresh meter issued to you. That may solve it. Or is could always be teenage daughters spending hours under the shower!

    Lord preserve us from the ipad app!!!! Nuff said.
     
  7. Feb 8, 2010 #6

    dlgoff

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    A note about Energy Cost Adjustment (ECA).

    When it comes to the dollar amount you are paying, your company might be buying power from other generation and transmission companies. The ECA is based on the actual monthly cost per kWh from these purchases and are reflected on your bill. The ECA is designed to allow for fluctuations in the cost of producing, or generating, electricity. This adjustment reflects the current month's increase or decrease in the cost of producing electricity as compared to the base rate.
     
  8. Feb 8, 2010 #7
    I would not recommend tampering with your utility companies power meter in anyway. It's a good way to get a hefty fine and a red flag over your house in some DEA database. I would use mgb's method of checking your power meter's reliability, but other then that there isn't much you can do. No one would want to make a product that relies on working in series with your utility providers power meter for the sake of monitoring power usage. Or at least I would only put such a system in a house while it is being built.
     
  9. Feb 8, 2010 #8

    russ_watters

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    Last edited by a moderator: Apr 24, 2017
  10. Feb 8, 2010 #9

    berkeman

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    Some of the new "smart meters" being installed definitely offer incoming power metering data versus time (hourly, daily, seasonally) to the homeowner. That's part of the smart metering concept...
     
  11. Feb 9, 2010 #10

    sophiecentaur

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    Nowadays, the supply companies are so hard pressed to provide capacity that they really want you to be aware of just how much power you are taking. Giving you the knowledge about what you are using and how much it costs you at any one time will induce you to use the stuff when they have it available. Everyone wins that way.
     
  12. Feb 9, 2010 #11
    After the huge flap in Bakersfield CA about suspected innacuracies of the new Smart meters, it would seem to me that more responders here would be suspicious of possible inaccurate power readings resulting in excessive home utility charges. And especially after the shenanigans of Wall Street and Washington. Most people here seem to trust their utility companies just fine and back them all the way. Maybe some of you even work for them and think it is fine for them to create even more layers of metering inscrutability that serve to better defeat homeowner attempts to determine true power usage that may differ from what a utility company states.

    CA Dept. of Weights & Measures slams gas stations hard with fines and costs if their pumps are found to be even the tiniest bit inaccurate in the stations' favor, perhaps due to their PRIVATE company status. I guess that's not the case with PUBLIC utilities, overseen by the State PUC, but with perhaps a more lenient attitude toward quasi-public Big Utilities.

    As I cannot find it here, I will go elsewhere for an answer to my question and I have emailed Smarthome.com along with others that make such metering devices.
     
  13. Feb 9, 2010 #12

    The Electrician

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    Russ Watters offered you one option; here's another:

    http://www.aemc.com/

    Have a look under "Power Quality Meters".

    You could also search the web for "power loggers".
     
  14. Feb 9, 2010 #13

    berkeman

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    I'd be interested in reading about that. Could you please post a link? Thanks.
     
  15. Feb 9, 2010 #14
    berkeman,

    I found this regarding the Bakersfield, CA smart meter's issue.

    http://www.greentechmedia.com/artic...rt-meters-slows-down-bakersfield-deployment/"

    As this blog describes, the meters are not made by utility companies, and they are supposedly being diagnosed by another 3rd party company to determine their accuracy. PG&E is a large company and they do screw things up when it comes to installation from time to time. Some of their most notable screw ups come in the form of gas line explosions:

    http://cbs13.com/local/rancho.cordova.explosion.2.894888.html"

    I don't think the meters are to blame for whatever trouble is happening with people's utility bills in Bakersfield, and I certainly don't think that it is a scheme to take more money from people. My intuition as an engineer tells me that if there is a problem it exists in a cross layering issue between the new meters and whatever PG&E database they are connected to.

    Overall though I support the implementation of the smart meters. If they can work right they can help clean up the losses in large power distribution networks.
     
    Last edited by a moderator: Apr 24, 2017
  16. Feb 10, 2010 #15
    In Canada all revenue meters must be certified by Measurement Canada... same as the calibration of the gas-pump at a gas-station or a scale at a grocery store.

    There are limitations & systemic errors typical in electronic meters that did not exist with old style eddy-current meters, but the overall accuracy of eddy current meters declines with time.

    If the loads are predominantly non-linear (ie. a pumphouse with VFD drives), then a modern electronic meter can be significantly off, depending on the type of drives in use. In installations where the load's power-factor is poor & a penalty is applied, not all electronic meters are equal to the task.

    I buy revenue power meters (I run a very small re-selling electric utility), and have always found obtaining the manuals & technical guides very easy & simply available on-line.

    If you want to obtain better resolution detail (for energy audits), then there are many excellent products available. for example : http://www.dentinstruments.com/" I own the Elite-Pro model for energy audits, and am happy with it.

    Many modern electronic meters have an alternate display mode that can be switched on for a while using a magnet. Look for a symbol on the meter face where the reed-switch is located (operates when a magnet swiped past). Now you will see a wealth of good information. The customer is allowed to do this. The customer is NOT allowed to attach any instrument or device ahead of the meter on the incoming service.
     
    Last edited by a moderator: Apr 24, 2017
  17. Feb 10, 2010 #16

    russ_watters

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    Do you have any sources that you can cite for this? Otherwise, you are engaging in crackpot speculation and that's not allowed here.
    ???? Your question has been answered. I gave you a link to a product that does exactly what you are looking to do.
     
  18. Feb 10, 2010 #17

    russ_watters

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    I recognize that you are just doing the research for someone else....

    If that's all there is to the Bakersfield issue, then at this point it does not provide a reason to suspect any more than normal, occasional meter errors. Indeed, I've worked in the utility cost analysis business and recall from studies that somewhere on the order of 1-2% of utility bills contain errors. This does not imply a conspiracy by utility companies to cheat us on our meter measurements.
     
    Last edited by a moderator: Apr 24, 2017
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