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#1
Old 10-05-2013, 02:30 PM
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Electric Clocks Running Fast?

In the main room of my apartment, there are three electric clocks with digital displays. One is the front panel of a clock/radio. Another is on the control panel of the stove. And the last is on the cable box (Verizon Fios, not actually cable, but that probably doesn't make any difference).

The clock/radio and the oven clock are running fast. The cable box clock is accurate (verified by checking against my cell phone and clocks displayed on television programs).

This is a new phenomenon. It started a few weeks ago. I've reset the clocks three times now, and they always gain on the cable box clock.

So what could make these clocks run fast?

They're not battery-operated. They get their power from the building electrical system. I don't know much about electricity (or about clocks, for that matter). I know that electric watches keep time by means of a vibrating crystal, a crystal that will vibrate at a known rate when an electrical charge is applied. Do electric clocks like the ones in my apartment work differently? Could it be that they tell time by keeping track of the 60-cycle fluctuation of alternating electrical current? And if so, would something weird about the building electrical supply be causing them to run fast? Could that even happen? Could their be some problem with power?

'm assuming that the time display on the cable box is getting a time signal from Verizon, and isn't actually a clock (that is, it isn't keeping time itself).

Very strange. Anyone have any idea what's going on?
#2
Old 10-05-2013, 02:38 PM
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You are not crazy

http://nbcnews.com/id/43532031/n.../#.UlBqXDK9KSM
#3
Old 10-05-2013, 02:56 PM
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Interesting. I was just going to assume Saintly Loser was crazy.

Saintly Loser, how far ahead are your clocks getting? How long did it take them to get that far ahead?
#4
Old 10-05-2013, 02:57 PM
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Quote:
Originally Posted by ZenBeam View Post
Interesting. I was just going to assume Saintly Loser was crazy.

Saintly Loser, how far ahead are your clocks getting? How long did it take them to get that far ahead?
The first time I reset them, they were ten or twelve minutes fast. I don't know long it took them to get that far ahead, because I didn't notice until they were already there.

After resetting them, seems like in about a week they're maybe three minutes fast. I really should start logging this -- then I could answer accurately.

Last edited by Saintly Loser; 10-05-2013 at 02:58 PM.
#5
Old 10-05-2013, 03:00 PM
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Are these clocks plugged in or battery operated. It should be noted that the article that Sigene posted is based on an 'experiment' that was slated to take place over a year ago and may not have ever happened it if it did happen it may not have been put in place. I didn't attempt to follow up on it. Besides, it's moot it any or all of the OP's clocks are 'off the grid' so to speak.

ETA I see they're electric. You could, if you really wanted, get yourself a multimeter that can read Hz and see if your power is cycle at 60Hz like it should be.

Last edited by Joey P; 10-05-2013 at 03:02 PM.
#6
Old 10-05-2013, 03:11 PM
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It sounds like your power frequency is off a little. I'd suggest trying an electric analog clock. They shouldn't be as sensitive to small freq changes. The motor could be thrown off by a big change but I suspect you're not off by very much.

As the OP suspected, digital clocks use the AC freq to count time. Analog do too (by how fast the motor turns with the gears) but are less sensitive.

Last edited by aceplace57; 10-05-2013 at 03:15 PM.
#7
Old 10-05-2013, 03:18 PM
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Heres a basic counter circuit. It provides output that lights up segments in the LED.

The AC gets filtered into a sync pulse. _____!_____!_____!_____! the counter counts the spikes. You can check that sync pulse with a logic probe (it lights up for each spike) or even look at it with an oscilloscope.

http://hyperphysics.phy-astr.gsu.edu...2/countdec.gif

Last edited by aceplace57; 10-05-2013 at 03:22 PM.
#8
Old 10-05-2013, 03:30 PM
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Overkill for an annoying fast clock. But line conditioners are strongly recommended by HP to protect their laser printers. We use them at my office to protect the web server and laser printers.

http://amazon.com/Tripp-Lite-LC1...ne+conditioner

Last edited by aceplace57; 10-05-2013 at 03:31 PM.
#9
Old 10-05-2013, 05:34 PM
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FWIW and maybe unrelated, I've had two Toyotas in a row with fast clocks. Yeah, they run a little fast, get a few minutes ahead, and I have to set them back.
#10
Old 10-05-2013, 05:48 PM
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Quote:
Originally Posted by Aeschines View Post
FWIW and maybe unrelated, I've had two Toyotas in a row with fast clocks. Yeah, they run a little fast, get a few minutes ahead, and I have to set them back.
No surprise - Japan is 10 or so hours ahead of you - the clocks are just trying to catch up.
#11
Old 10-05-2013, 06:04 PM
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Quote:
Originally Posted by aceplace57 View Post
It sounds like your power frequency is off a little. I'd suggest trying an electric analog clock. They shouldn't be as sensitive to small freq changes. The motor could be thrown off by a big change but I suspect you're not off by very much.

As the OP suspected, digital clocks use the AC freq to count time. Analog do too (by how fast the motor turns with the gears) but are less sensitive.
Analog clocks are directly timed to the frequency. The motor will turn at 3600 or 1800 RPM at 60 cycles. At 60.1 cycles they will turn 3606 or 1803 RPM. In every hour the clock will gain 6 seconds. or in a day 144 seconds a day. But 0.1 cycles is a large drift off set point. A generator with a single stage mechanical governor should hold under 0.1 cycles. I would expect the gride to be +- 0.001 cycles. And advarage to 0
#12
Old 10-05-2013, 06:48 PM
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Don't know about US Power generators, but in the UK you are limited to +/- 0.0000001Hz over 24 Hours. A bit tighter than the 'Euro-grid'.
Power networks fascinate me, the idea of a society that wants power on their terms, at their rates, owned by their own nationals and still delivering a profit to a Pension. Appropriate Emoticon.
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#13
Old 10-05-2013, 06:53 PM
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It sounds like an electrical problem with the grid. I read a newspaper article recently about some place that for some reason had a change in the hz, with resultant clock problems. I wish I could remember more about it, but at the time I merely noted it as interesting and went on to read the comics page. That only your two electric clocks are off is the main indictment.
#14
Old 10-05-2013, 07:10 PM
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Quote:
Originally Posted by Aeschines View Post
FWIW and maybe unrelated, I've had two Toyotas in a row with fast clocks. Yeah, they run a little fast, get a few minutes ahead, and I have to set them back.
Same experince with the clock on my Prius.
#15
Old 10-06-2013, 06:53 AM
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Quote:
Originally Posted by Saintly Loser View Post
This is a new phenomenon. It started a few weeks ago. I've reset the clocks three times now, and they always gain on the cable box clock.

So what could make these clocks run fast?
It could be dirty power. If a clock is keeping time by counting power cycles then spikes in the powerline can be counted and make the clock run fast. This is more likely in places with motors, fluorescent starters or other devices which create interference. If you or your neighbors have new devices which may be causing dirty power this might be the cause.

In this case the remedy is a low pass filter on the power wires. You can probably buy them commercially (be careful as many may be just an empty black box) but also build one yourself with a couple of inductors and capacitors or salvage from an old PC power supply.
#16
Old 10-06-2013, 09:01 AM
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Quote:
Originally Posted by Sigene View Post
That's fascinating. So plug-in clocks will no longer be reliable. I don't think Hydro-Quebec (which is not connected to the North American grid) is doing the same although I have only one or two clocks that plug in.

Back in the 50s I found out that the electric company varied its frequency during the wee hours to keep their clocks right on time, which of course kept everyone else's on time too.
#17
Old 10-06-2013, 10:58 AM
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According to Sigene’s link it is an experiment:

Quote:
"Is anyone using the grid to keep track of time?" McClelland said. "Let's see if anyone complains if we eliminate it."
So is there any mechanism provided for affected people such as Saintly Loser to actually make complaints to the FERC (or whoever), or is the “experiment” rigged?
#18
Old 10-06-2013, 11:03 AM
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Quote:
Originally Posted by Aeschines View Post
FWIW and maybe unrelated, I've had two Toyotas in a row with fast clocks. Yeah, they run a little fast, get a few minutes ahead, and I have to set them back.
Interesting. I have a Scion (made by Toyota) which in eight years I've never had to adjust the clock (other than for Daylight Savings Time). It's spooky accurate.
#19
Old 10-06-2013, 01:37 PM
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The experiment was slated to occur in July, 2011, according to the article's time stamp (6-24-2011), so if it did take place, it was over last year.
#20
Old 10-06-2013, 02:30 PM
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Quote:
Originally Posted by pdunderhill View Post
Don't know about US Power generators, but in the UK you are limited to +/- 0.0000001Hz over 24 Hours. A bit tighter than the 'Euro-grid'.
The U.S. has never been that tight.

To start with, the U.S. doesn't have just one grid. It is split into three different grids. There's an eastern grid, a western grid, and Texas (because Texas always has to be off on its own...). The Texas grid, being the smallest, has always been the most tightly controlled. I believe that they used to adjust them all to within one second over 24 hours. During the day, though, each grid could lag by several seconds, with Texas typically having the least lag of the three.

The electrical load tends to slow down the grid, so the grids will lag more and more during the day while they are under heavy load. At night when the load drops off, the grid frequency would be sped up a bit to get the long term drift back down under a second.

Controlling the grid frequency isn't easy, by the way. If you have a single generator, it is easy to control. You just add more power to speed it up and remove power to slow it down. If you hook a second generator to that, the two end up locking together in frequency. If you add power, it speeds up itself and the difference in speed causes energy to flow from one generator to the other, speeding it up too. If you remove power, the generator starts to slow down and energy from the other generator flows into it, speeding it up like a motor. With only two generators, each generator can speed up or slow down a bit, but they are basically dragging the other one with it so it is much more difficult. Add in a few more generators, and the "grid" becomes too powerful for any single generator to affect it much. If you add more mechanical power to your generator, it can't speed up because it can't push all of those other generators faster. There are too many of them. So all that happens is your generator produces more power for the grid. If you remove mechanical power, all of those other generators continue pushing it, and your generator becomes a motor, powered by the grid. So by adding and removing mechanical power you can control how much power your generator adds to the grid (or even draws from it, if you remove too much), but you can no longer control the speed of your single generator.

Speeding up or slowing down the entire grid now becomes much more difficult. What you have to do is coordinate all of the generators (or at least the majority of the most powerful ones) and have them all speed up or slow down at the same time. It's nowhere near as simple as just turning a dial somewhere.

ETA: Also, keep in mind that the entire UK grid is probably about roughly a third of the size of the Texas grid, and that's our smallest grid. The smaller the grid, the easier it is to control.

Last edited by engineer_comp_geek; 10-06-2013 at 02:33 PM.
#21
Old 10-06-2013, 03:18 PM
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Quote:
Originally Posted by engineer_comp_geek View Post
The U.S. has never been that tight.

To start with, the U.S. doesn't have just one grid. It is split into three different grids. There's an eastern grid, a western grid, and Texas (because Texas always has to be off on its own...).
More generally, North America has four grids, with the fourth being Quebec (because French Canadians always have to be off on their own...)

Quote:
Add in a few more generators, and the "grid" becomes too powerful for any single generator to affect it much. If you add more mechanical power to your generator, it can't speed up because it can't push all of those other generators faster. There are too many of them. So all that happens is your generator produces more power for the grid. If you remove mechanical power, all of those other generators continue pushing it, and your generator becomes a motor, powered by the grid. So by adding and removing mechanical power you can control how much power your generator adds to the grid (or even draws from it, if you remove too much), but you can no longer control the speed of your single generator.

Speeding up or slowing down the entire grid now becomes much more difficult. What you have to do is coordinate all of the generators (or at least the majority of the most powerful ones) and have them all speed up or s.
Does adding more power speed up the grid in some way proportional to the added power? For example, if my generator supplies 0.1% of the grid's power, and I double its power output, does the grid frequency speed up by something like 1 part in 1000?


Just because it's interesting, here's a site which reports the real-time mains frequency of Europe. Clicking on Graph, it will start a graph of the frequency over the previous five minutes. I couldn't find a similar site for the US. Unfortunately, it's not working at the moment. It was working earlier today, so hopefully it will come back up.
#22
Old 10-06-2013, 04:26 PM
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Quote:
Originally Posted by TSBG View Post
Same experince with the clock on my Prius.
Me three. No idea why, since these are DC circuits and not reliant on 50/60 hz. Also, my furnace thermostat clock gains time, but nothing else in the house does (stove, micro, DVD, etc.).
#23
Old 10-06-2013, 06:11 PM
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I recall reading somewhere (no cite) that this is a problem caused by the increase in the use of wind power and solar generators.

Because the input from these sources is so random, it is technically a nightmare to synchronize their input to the the grid. Accordingly, as they cut in and out, they cause frequency fluctuations, and this is manifest in the kind of problems described here.

The article I read said that this problem is only going to get worse as more of these alternative generators are connected to the grid; and all electrical equipment that relies on precise timing will soon need auxiliary power conditioners.
#24
Old 10-07-2013, 12:54 AM
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Originally Posted by Polar Iceman View Post
I recall reading somewhere (no cite) that this is a problem caused by the increase in the use of wind power and solar generators.

Because the input from these sources is so random, it is technically a nightmare to synchronize their input to the the grid. Accordingly, as they cut in and out, they cause frequency fluctuations, and this is manifest in the kind of problems described here.

The article I read said that this problem is only going to get worse as more of these alternative generators are connected to the grid; and all electrical equipment that relies on precise timing will soon need auxiliary power conditioners.
I would think that the amount of power supplied to the grid by wind and solar is a small % of the total power of the grid. So they may have some effect but it would be a small amount.
#25
Old 10-07-2013, 02:23 PM
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Thanks for all the explanation -- quite a bit of it is over my head, but I get the general idea.

One more question -- does this necessarily have to be caused by the power company, or can it be a local phenomenon -- something happening after the power enters my apartment building, but before it reaches my apartment?

It's still doing it, by the way, and I'm estimating the clocks are gaining somewhere in the neighborhood of a minute a day.
#26
Old 10-07-2013, 05:31 PM
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Quote:
Originally Posted by Saintly Loser View Post
One more question -- does this necessarily have to be caused by the power company, or can it be a local phenomenon -- something happening after the power enters my apartment building, but before it reaches my apartment?
I already answered that. If it is caused by dirty power it can be caused by equipment on your premises or on your neighbors' premises up or down the line.
Quote:
It's still doing it, by the way, and I'm estimating the clocks are gaining somewhere in the neighborhood of a minute a day.
Assuming you are connected to the general grid I do not believe this can be due to frequency shift. My first suspect would be dirty power and the first thing I would try would be a low pass filter and/or think if any new devices are online and try shutting those down and see if this corrects the problem.

Note that a surge protector is not a low pass filter and will not correct the problem. Only a low pass filter will make sure high frequency spikes do not reach the clock.
#27
Old 10-07-2013, 06:24 PM
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Saintly Loser, have you bought anything electronic recently? Can you ask your neighbors if they've noticed anything?
#28
Old 10-07-2013, 07:34 PM
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Originally Posted by ZenBeam View Post
Saintly Loser, have you bought anything electronic recently? Can you ask your neighbors if they've noticed anything?
No, no new electronics. I do plan on asking some of the neighbors. It's a big building -- 400 units. If something is going on, I can't be the only one having this problem.
#29
Old 10-07-2013, 09:39 PM
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You know whats funny is I am a fire alarm technician and I install fire alarm panels, and I have noticed that between my semi annual fire alarm inspections, the on board clocks for the fire panels are usually between 5 and 10 minutes off. I correct it, but always assumed that the local power plant isn't keeping the hertz square on 1 per second (60 hertz). I am in the Houston area, so if its to be blamed on the power grid, then Texas's grid isn't as tight as it would seem.
#30
Old 10-08-2013, 06:01 AM
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Originally Posted by cochrane View Post
The experiment was slated to occur in July, 2011, according to the article's time stamp (6-24-2011), so if it did take place, it was over last year.
So they did the experiment, and nobody cared. Now they just let the frequency drift...

Some mains-powered Digital Electronic clocks count the number of cycles. They will run fast if there is extra garbage on the line, or if the line runs fast.

Mains powered analog clocks run synchronously with the the line. They will not notice garbage (they will run hot if there is too much, but for a clock that is never going to happen). They will slow down and speed up as the line frequency changes.

Here in Melb.Aus, the company used to guarantee something like 1.5 second total accuracy, 0.5% accuracy per cycle. Dunno what it is now. Our line frequency is different, so American clocks don't work here (even if you shift the transformer taps correctly). And printer page rates are slower. And the turntable of my Microwave oven turns more slowly, with fewer total turns.
#31
Old 10-08-2013, 09:32 PM
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Nothing to add, really. Just that this is a really interesting thread.
Now that y'all have pointed this out, I plan on keeping an eye on the different clocks to see if I notice a difference.
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#32
Old 11-22-2013, 08:12 PM
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How are things going with your clocks, saintly Loser?

While doing some searches related to another thread, I came across an article, Solving the fast clock problem (PDF), from almost 20 years ago that talks about electric customers with a similar problem, and describes how a clock can run fast due to line noise as sailor said. With lots of nice pictures of dirty power.

In one case in the article, the cause of the dirty power was arcing on a faulty disconnect at a power substation. In another, it was a neighbor's electronic air ionizer.
#33
Old 05-01-2015, 07:10 PM
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Electrical clocks - running fast after installing roof top Solar

Very interesting. We installed roof top Solar panels two weeks ago and the electrical clocks started running faster, Gaining as much as 30 minutes in 6 hours. These run fine at night time. I called the solar company and also the tech support for the invertor manufacturer.
Both tech reps stated that they never heard of it before. I ask the question on Google and the first response explains it completely. It is the power source cutting in/out.

The electrical meter has an indicator that flips "left to right" to "right to left" depending upon the consumption and the generation level. This flip/flop is the real cause.

I will try a UPS outlet. Hopefully that will confirm it.

thanks.
#34
Old 05-01-2015, 09:51 PM
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When I was in the USCG, I was a LORAN Tech and then an instructor in the LORAN school where I taught the care and feeding of rubidium and cesium frequency standards. Anyway, for the precision we were concerned with, we didn't bother with the peaks of any amplitude modulated pulses or sine waves. We used the negative-going crossovers, that is, when the sine wave crossed the zero V (ac) line on the o'scope.

But any motor where the rpm is dependent on the frequency of the incoming Vac is going to be a problem. I guess you should try to find analog clocks that use DC motors and quartz digital clocks.
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