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electronic clocks running fast?

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AdAPTR

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Hi, this is my first post here, but I found a question that begs for an answer.

Is it possible that electronic clocks e.g. alarmclocks, clocks on microwaves and vcr's, run faster because of the frequency of the AC power being too high?

Hope someone knows the answer to this one!:grin:
 

mister_rf

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Actually some old LED clocks did not have a crystal, they had a counter that counted the 50 (60) cycles power, so an intermittent connection or frequency variation can therefore lead to create extra pulses that will be counted.
That will make it run faster.
 

AdAPTR

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AH! so new clocks wouldn't do that, I mean, not all electronic clocks all over town? I am asking because in Italy there is a village where ALL the e-clocks in town were sped up... And the "official" reason given was that the power freq was to high. But I though already that a clock with a crystal (like every clock since almost forever) shouldn't do the speeding up thing... So the "official" reason is bull? Sure?
 

keith1200rs

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A lot of time switches rely on the mains frequency to drive their motors.

Keith
 

AdAPTR

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What switches and motors are you talking about? I do not know much about electronics , but I am quite sure there are no motors in most modern electronic clocks, not in mine anyway....
 

BradtheRad

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I once heard a story about the electric companies constantly adjusting the generators so they would average 60 Hz over the long term.

If for any reason the generators slowed down, clocks all over town lost time. The clocks had AC motors inside. Therefore the electric company would speed up the generators for a while until everyone's clock regained the correct time. A good story to entertain dinner guests with.

However someone in the know told me that's no longer necessary in the US. Today power companies are able to maintain 60 Hz exactly.

There's a pressing reason. We have a nationwide grid that absolutely must be kept in synch. Any power plant that departed the slightest bit from the standard would start producing molten copper instead of kilowatts.

However that story still may be true in smaller communities, although I understand electric clocks have been transitioning to crystal-controlled time, same as our electric wristwatches.
 

AdAPTR

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But that was not the question, I know that there a motorized timers and antique alarm-clocks with motors and those flipping numbers. I used to have one of those. I am talking about electronic, non motorized clocks, which we know have crystals in them, that have a certain frequency. Now are they going to run faster if the power supplied is of a higher frequency? My guts say no, but then again, I do not know much about electronics, just the basics.

---------- Post added 11-06-11 at 00:05 ---------- Previous post was 10-06-11 at 23:59 ----------

I once heard a story about the electric companies constantly adjusting the generators so they would average 60 Hz over the long term.

If for any reason the generators slowed down, clocks all over town lost time. The clocks had AC motors inside. Therefore the electric company would speed up the generators for a while until everyone's clock regained the correct time. A good story to entertain dinner guests with.

However someone in the know told me that's no longer necessary in the US. Today power companies are able to maintain 60 Hz exactly.

There's a pressing reason. We have a nationwide grid that absolutely must be kept in synch. Any power plant that departed the slightest bit from the standard would start producing molten copper instead of kilowatts.

However that story still may be true in smaller communities, although I understand electric clocks have been transitioning to crystal-controlled time, same as our electric wristwatches.
So? Do you believe the "official" reason given? Taking into account that IMHO ALL electronic clocks made after 1985 or so use crystals, is it still likely that a whole village will experience speeding up electronic clocks (alarms, vcr, microwave, dvr, etc etc) because of power freq. being too high?

Very interesting stuff this.... :)
 

BradtheRad

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Such an explanation could not possibly apply to today's computerized equipment (vcr, microwave, dvr, etc).

If... that's IF, it is true that everyone's appliances gained the same amount of time, then we'd have to believe the keeper of the tower in town square set the clock wrong, and everyone set their clock to that...

or else...

it was a hypothetical time warp bubble or somesuch, that encompassed the entire town unbeknownst, and slowed down all the vibrating crystals in those appliances.
 

AdAPTR

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@BradtheRad

it was a hypothetical time warp bubble or somesuch, that encompassed the entire town unbeknownst, and slowed down all the vibrating crystals in those appliances.
( I think you really meant SPED UP here?)

Well, that was exactly why I came here, because I did not believe the official explanation, just to check if what they said could be true.

I saw it on the Dutch news yesterday: http://nos.nl/video/247495-klokken-sicilie-op-hol.html

You have to speak Dutch or Italian to really get it, but it boils down to this:

Because of maintenance of the Sicilian power-grid they experienced "shocks in the frequency". Instead of 50 Hz they were running on 50.13 Hz and this caused the clocks to run fast.....
 

KJ6EAD

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In the U.S. many of us now have clocks that work from an internal crystal controlled oscillator as usual but also synchronize to a radio signal transmitted by the government. WWV (radio station) - Wikipedia, the free encyclopedia

Some clocks and other timekeeping devices such as phones now read the time from the GPS satellites.

iNRiM has a time base website that explains their time synchronization signals that are transmitted via broadcast TV and radio Tempo campione italiano.
 

srizbf

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earlier type clocks used sychronous motors for showing time.
as it is mains frequency driven , any variation in freq will have a corresponding time variation.

after that some electronic clocks which is clocked by the frequency of the grid were there for a short time.(only very brief period --1980's)

but now , all electronic clocks are driven by crystal inside and the clocks will not have any effect on mains frequency.

what is the type of all clocks that you are referring to in your doubt ?

your message of "...Instead of 50 Hz they were running on 50.13 Hz and this caused the clocks to run fast....."
will not have any noticable effect even in electric clocks of motor types in a short time of observation.
 

andre_teprom

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...non motorized clocks, which we know have crystals in them, that have a certain frequency. Now are they going to run faster if the power supplied is of a higher frequency?...Taking into account that IMHO ALL electronic clocks made after 1985 or so use crystals, is it still likely that a whole village will experience speeding up electronic clocks (alarms, vcr, microwave, dvr, etc etc) because of power freq. being too high?...
Maybe an indirect thermal effect could be the main reason to change crystal frequency.
If equipment input voltage supplied increases, dissipated energy will be higher, and accumuladet temperature too.

Here in my coutry, we must perform adjustements after some months due long term temperature range during changing seasons.
See the crystal behaviour over temperature domain.



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BradtheRad

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I wrote:

"it was a hypothetical time warp bubble or somesuch, that encompassed the entire town unbeknownst, and slowed down all the vibrating crystals in those appliances."
( I think you really meant SPED UP here?)
Yes. My mistake. In fact, in the recesses of my mind I thought... but I did not want to say out loud...

The rest of the earth had its timekeeping slowed down (all except for the Sicilian town)... having been put in a capsule and propelled at enormous speed.

This has a remote scientific basis. A similar effect is observed to happen to people's watches when they come back from a plane flight or space flights.

Guess it's more like a tenuous scientific basis. So I was reluctant to suggest the idea.
 

AdAPTR

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@bradtherad: NP! :p

@andre_teprom: So far this is the most likely scenario I have heard. Sicily is an island and it could have been in a "weather bubble" of it's own.

I wonder why they would come up with an explanation that even me (someone who doesn't know electronics) can spot as a lie?

Thanks so far all you guys! I am wondering what else comes up..... :)
 

Zanderist

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I've heard about this on ships (steam turbine ships from my experience), since the ship's service generator isn't constant the frequency out put will vary with the load put on the system. That's why the ships main clock is mechanical; However since newer clocks have a crystal in them this shouldn't be the case. I wonder if this is comparable to pwm.
 

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