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Master Brian
02-10-2009, 09:59 AM
My brother noticed a while back that my meter wasn't spinning. I had electrical stuff such as lights, etc on inside the house, so I know I was using electricity. In any case, I thought it was odd and checked it again later, it was spinning, so I forgot about it.

A few days ago, my brother was over again and looked at the meter and again, it wasn't spinning. I looked later and it was spinning again. Is this common? Shouldn't it spin any time there is power being consumed?

I know via my $200 electric bill last month, I am using electricity and that the electric company is charging me. My question is, if it should be spinning pretty much all the time, because power is always being used, is it likely faulty? If so, can it be spinning too fast as well as not spinning at all?

I plan on calling the electric company to have them test it, but want to know what I'm up against. I'd like to be educated prior to calling....

jadnashua
02-10-2009, 10:18 AM
The spin rate is proportional to your use...so, it could be working normally. A few lights aren't a big load and while turing, it might only be moving slowly - like watching the hour hand on a clock. Throw in the furnace, dryer, stove, etc., and you should see it go faster.

Master Brian
02-10-2009, 10:47 AM
The spin rate is proportional to your use...so, it could be working normally. A few lights aren't a big load and while turing, it might only be moving slowly - like watching the hour hand on a clock. Throw in the furnace, dryer, stove, etc., and you should see it go faster.

I know it's proportional, which is why I'm a bit concerned that it isn't working correctly. I am pretty sure I turned on a larger load the first time, it wasn't moving to see if that was the case and it didn't budge. I was going to call it in, but when I went back it was spinning and thus I figured it was a fluke or something. I had checked it several times when I thought about it and it was always spinning....but this 2nd time, starts to concern me.

I've never seen a meter not spinning at all when something was turned on.

Scuba_Dave
02-10-2009, 01:34 PM
With small loads I used to look at my meter - didn't look like it was moving - like watching a minute hand
Now I have a digital meter

Ian Gills
02-10-2009, 02:28 PM
Hit your brother and tell him to stop winding you up.

Hit him extra hard if he asks you to go to the store room to get a bag of sparks for the grinder; or,

to go get a right handed hammer; or,

to get a long wait; or,

"Skyhooks" to hang the lights; or,

dark black paint or checkered paint; or,

a tin of compressed air.

codeone
02-10-2009, 05:23 PM
They can spin very slow if you have a small load, sometimes hard to detect.
A good way to check is to right down the dial #'s and go back at the same time each day for a month. Then compare it to your power bill. ask for the rate their charging you then compare. Your bill sounds like its working though.
It doesnt hurt to have the power co check. If its not working properly they usually wont charge you anymore (such as an estimated bill). If they find it first sometimes they do go back and estimate. Not a bad idea to keep an eye on till you are sure

jar546
02-10-2009, 06:49 PM
I think there is a problem with your brother, not the meter.

Cass
02-11-2009, 04:14 AM
It may be that it is not turning...if so it is not your problem...you do not own the meter...report it if you think it is not turning and let the utility worry about it...
I had a friend that operated a buisness that used huge amounts of electricity and evey month his bill was exactly $39.00 or something like that...he notified the utility 3 seperate times, in writing, and explained the situation and every time they would come out and check and tell him every thing was correct...it was not but they never corrected the problem...it was like this from the time he bought the buisness until he sold it 13 years later.

hj
02-11-2009, 07:29 AM
His electrical system could be like a gas system a restaurant in Chicago had. His gas bill every month was about $12.00 at the time even though he had a huge kitchen. When my dad had to work on it one time the meter did not turn off the ovens. There was a "wildcat" gas line into the basement right off the gas main, (in Chicago the mains are low pressure so he did not need a regulator), and was thus unmetered. This had been going on for decades, probably since Prohibition days. One morning my dad got an emergency call from the restaurant. Apparently one of the wino customers had been doing some cheap repairs and had found the gas line connection. When he was not hired to do the kitchen remodel he blew the whistle to the gas company and they had come in and cut the line and welded it shut. We had to revise the gas system so they could serve food that afternoon. The gas company only fined them a few hundred dollars for the years of stolen gas.

SewerRatz
02-11-2009, 07:55 AM
[QUOTE=hj;184171 (in Chicago the mains are low pressure so he did not need a regulator)[/QUOTE]

That is correct, They have block regulators, that supply the whole block with low pressure gas. I recall a a while back a block regulators failed and many people had hissing noises from their stoves due to the spike in the gas pressure which blew out the pilot lites. Others reported 6 to 8 inch flames from their pilots. here's a article on one of the incidents. http://www.chicagoreporter.com/index.php/c/Cover_Stories/d/A_Close_Call_for_Chicagoans:_Only_Luck_Saved_Hegew isch_from_the_Same_Fate_as_River_West

Master Brian
02-11-2009, 10:04 AM
They can spin very slow if you have a small load, sometimes hard to detect.
A good way to check is to right down the dial #'s and go back at the same time each day for a month. Then compare it to your power bill. ask for the rate their charging you then compare. Your bill sounds like its working though.
It doesnt hurt to have the power co check. If its not working properly they usually wont charge you anymore (such as an estimated bill). If they find it first sometimes they do go back and estimate. Not a bad idea to keep an eye on till you are sure

Well, I did check the numbers the 1st time and over an hour later nothing had changed and electricity had been used. It seems I had even turned on the A/C or dryer, that is why it doesn't make sense.

When I went back later and it was turning, I kind of thought, they'd say what you guys are saying, that I just didn't use enough electricity and from there on out, it seemed to always be turning. With it stopping again, something has to be up. This last time, lights in several bedrooms were on, as well as the kitchen, living and dining room, a 32" LCD TV, DVR, Fan for Furnace set to ON, garage light, two outdoor lights, largish fridge, a small fridge and a large upright freezer. Probably many other small power drain items as well. Is all of that really a small enough drain that the meter shouldn't/wouldn't be turning?

I know some say not to report it, but not only do I prefer to be honest, I also tend to think if it's possible for it to spin to slowly, it has to be possible for it to spin to quickly.

I'm not arguing that the electric company isn't charging me correctly based on the meter readings, I'm saying I question if it is possible for the meter to not be functioning correctly. i.e. spinning too slow, which is good for my $$, or to quickly, which is good for electric company's $$. I don't really see how reading the numbers does anything except confirm they are charging me correctly based on the meter readings. That's not really the debate.

I want to know is it possible for the meter to spin to quickly, thus giving a false high?

Bill Arden
02-11-2009, 02:21 PM
It is possible for the magnetic bearings to go bad or the gears to stick and the disk will then only turn when there is lots of load.



I want to know is it possible for the meter to spin to quickly, thus giving a false high?

It is also possible for lighting strikes to demagnetize the break magnets and make it spin faster. however that would cause a higher bill.

It would be really hard for it to spin "too fast" since most AMR(Automatic Meter Reader) devices are designed for a wide range of speeds.

Mikey
02-12-2009, 03:54 AM
My old spinning-disk meter was replaced by the utility with a fancy new digital meter from Itron. In their literature, Itron says that "with its low starting watts and low watts lost, the CENTRON meter captures more energy consumption than was measured in the past by electromechanical meters." Neither Itron nor the utility have been able or willing to quantify that.

But obviously mechanical meters have some problms, and yours seems to have more than most. If you're having trouble sleeping nights fearing you aren't paying enough, by all means call your utility and ask them to check the meter. Maybe they'd even swap it for one of these new ones, which will properly measure the energy consumed by the LED on your cellphone charger...

Master Brian
02-12-2009, 08:16 AM
But obviously mechanical meters have some problms, and yours seems to have more than most. If you're having trouble sleeping nights fearing you aren't paying enough, by all means call your utility and ask them to check the meter. Maybe they'd even swap it for one of these new ones, which will properly measure the energy consumed by the LED on your cellphone charger...

I'm definately not having trouble sleeping because I fear not paying them enough. I do not however want to pay them too much either!

Master Brian
02-12-2009, 08:18 AM
It is possible for the magnetic bearings to go bad or the gears to stick and the disk will then only turn when there is lots of load.



It is also possible for lighting strikes to demagnetize the break magnets and make it spin faster. however that would cause a higher bill.

It would be really hard for it to spin "too fast" since most AMR(Automatic Meter Reader) devices are designed for a wide range of speeds.

That is what I was curious to know, thanks!

Bill Arden
02-13-2009, 02:33 AM
In their literature, Itron says that "with its low starting watts and low watts lost, the CENTRON meter captures more energy consumption than was measured in the past by electromechanical meters." Neither Itron nor the utility have been able or willing to quantify that.

I've done some tear down analysis of the centron meter. It counts each watt hour, but.... it lacks strong lighting protection. So one really strong zap and it's dead, no display, no readings, nothing.

Then again this is probably better than the old mechanical meters since it is likely to be within 2% until it dies.

Mikey
02-13-2009, 07:25 AM
Interesting, in that they're installing them here in the lightning capital of the US. I guess I should just hope it strikes early in the billing cycle :D. Have you found the smallest load it will accumulate? i.e., if I present a small load for a long time (e.g., .001A @ 120V for 1000 hours) will it do the integration properly? How about .0001A for 10000 hours? etc.

Master Brian
02-13-2009, 09:08 AM
The question I have is if they are more accurate, is that a good thing or bad thing for the end consumer?

From what has been posted, it seems obvious that they are better at picking up the small loads from things like cell chargers and TV's that are turned off, but still consuming power, which is bad for the consumer.

So maybe the real question should be, are they more accurate as far as not "over-reading" the bigger loads. I'm not sure how to state this correctly, but it would seem to me if the dial type aren't real accurate on small loads, then they wouldn't be real accurate in measuring load fluctuations. Think of the A/C cycling, if the dial type is slower to react, would it still charge for the higher demand for a few seconds/minutes even after the A/C has been turned off. Does that make sense?

Mikey
02-13-2009, 12:20 PM
That would be my guess. The mechanical nature of the device can probably be compared to a flywheel, the end result being a smoothing of the load as seen by the measuring mechanism -- geared dials, usually. The end consumer will win some/lose some, but I have no idea how it would net out. Depending on the sampling interval of the electronic meter, it could be as accurate as desired, which would certainly be fair, but may result in an increase or decrease in charges, based on the nature of the load and the characteristics of the mechanical meter. Judging from Itron's sales pitch, I'd be surprised if it were a decrease.

Master Brian
02-13-2009, 12:36 PM
That would be my guess. The mechanical nature of the device can probably be compared to a flywheel, the end result being a smoothing of the load as seen by the measuring mechanism -- geared dials, usually. The end consumer will win some/lose some, but I have no idea how it would net out. Depending on the sampling interval of the electronic meter, it could be as accurate as desired, which would certainly be fair, but may result in an increase or decrease in charges, based on the nature of the load and the characteristics of the mechanical meter. Judging from Itron's sales pitch, I'd be surprised if it were a decrease.


I don't know Itron's sales pitch, but I'd be shocked that the electric company would install a device, which they deemed might possibly end up costing them money through lower meter readings. Of course, I also would be shocked if Itron would use that as any sales pitch, since it isn't the end user that is buying the meter. Of course, if these meters were capable of saving the electric company large amounts of money, they'd replace all of the old ones ASAP.

I do know that the water dept is slowly replacing all of the old water meters in the city. The new ones, don't require the reader to get out of their vehicles to read them or to find out if they've been tampered with. I wonder how long before water, gas and electric meters are controlled from a central station like cable TV is now doing....

Bill Arden
02-14-2009, 09:55 PM
The mechanical meters tend to slow down with time and therefore customers tend to see there bills go up after replacement.

I don't see making the meters more accurate as a bad thing since it does not actually increase the price consumers pay. This is because of what's called the "pool". If all the meters were slow it would just cause the price per KWh increase until the difference was made up.

I am guessing that the centron meter can measure loads down to about 1 watt.
200 amps / 16,384(14 bits) = .012 amps
.012 amps * 120V = 1.4 watts

Eventually we will get TOU(Time of use) meters and that will make things both more confusing and also better for renewable energy.

Lets just hope the power company does not take a que from the phone company.
Sarcasm-> "on the x plan you get x price for the first x Kwh's unless it's a night or a weekend... :rolleyes:

Bill Arden
02-14-2009, 10:02 PM
That would be my guess. The mechanical nature of the device can probably be compared to a flywheel, the end result being a smoothing of the load as seen by the measuring mechanism -- geared dials, usually. The end consumer will win some/lose some, but I have no idea how it would net out. Depending on the sampling interval of the electronic meter, it could be as accurate as desired, which would certainly be fair, but may result in an increase or decrease in charges, based on the nature of the load and the characteristics of the mechanical meter. Judging from Itron's sales pitch, I'd be surprised if it were a decrease.

Actually both average out current variations so they aren't affected much by the current wave shapes.

The mechanical disk averages the impulse energy so that a short high current pulse pushes it just as hard as a long low current pulse.

The electronic unit uses a low pass filter to prevent frequency below the Nyquist frequency. http://en.wikipedia.org/wiki/Nyquist_frequency

Mikey
02-15-2009, 03:24 AM
...
Eventually we will get TOU(Time of use) meters and that will make things both more confusing and also better for renewable energy.
...

TECO is touting a new "RSVP" (Residential Service Variable Pricing) plan, which replaces their old time-of-day service plan. It divides the day into 4 pricing periods. P1 thru P3 are defined in a complicated schedule which changes between summer & winter, with rates from $0.03719 to $0.17839 per kWh ("standard" rates are now $0.07331 (up to 1000 kWh) and $0.08331 (over 1000 kWh). P4 is a "critical" period, which they can apparently define on the fly, at $0.65377 per kWh. P4 can only be invoked a maximum of 134 hours per year.

It looks like, with intelligent use of a humongous battery bank, you might be able to move your utility consumption to P1 to charge the batteries, and use battery power during P3 and P4 (if it's ever invoked). If my figures are right, you could save a minimum of $0.03612 per kWh, or about $520/year for 1200 kWh per month. It's probably not enough to pay for the batteries, chargers, switches, and controls over time, but it's fun to think about. You might be able to combine it with a solar array to grab some tax credits. I was told they wouldn't allow that tactic under the old time-of-day plan, but haven't asked about RSVP policy; I doubt it's changed.

Nate R
02-15-2009, 06:59 AM
I do know that the water dept is slowly replacing all of the old water meters in the city. The new ones, don't require the reader to get out of their vehicles to read them or to find out if they've been tampered with. I wonder how long before water, gas and electric meters are controlled from a central station like cable TV is now doing....

Our local utilities are working towards that route. At my house, Water, Gas and Electric all are automatically read. I never see a meter reader, and my usage is always actual. I like knowing it's not an estimate.