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Power Grid Change May Disrupt Clocks

timothy posted more than 3 years ago | from the let's-make-y2k-feel-dumb dept.

Power 439

hawguy writes with an AP story about upcoming tests of greater allowed variation in the frequency of the current carried on the U.S. electric grid: "A yearlong experiment with the nation's electric grid could mess up traffic lights, security systems and some computers — and make plug-in clocks and appliances like programmable coffeemakers run up to 20 minutes fast."

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"Clocks" (2, Informative)

jra (5600) | more than 3 years ago | (#36562086)

Clearly, whomever thought this was a Pretty Neat Idea hasn't read this:

http://yarchive.net/car/rv/generator_synchronization.html [yarchive.net]

and doesn't understand what happens when you're even a bunch of *degrees* out of sync, much less a few decihertz. We don't have *near* enough HVDC intertie to make this not matter, and I can't imaging how they think this is gonna work -- nothing at all on NERC's website to say what's *really* gonna happen, either.

Love all the warning, too.

Re:"Clocks" (1, Informative)

Anonymous Coward | more than 3 years ago | (#36562202)

"whom" is for objects in speech. For subjects, you want to use "who".

Re:"Clocks" (1)

Anonymous Coward | more than 3 years ago | (#36562236)

"whom" is for objects in speech. For subjects, you want to use "who".

So, is it "who is an pedantic ass" or "whom is a pedantic ass"? Doesn't really matter because the answer is "you are a pedantic ass".

Re:"Clocks" (2, Insightful)

gottabeme (590848) | more than 3 years ago | (#36562560)

"Who" would be correct.

It will be a sad day when no one cares enough about language and communication to politely correct someone's grammar mistakes, and when those who try are shouted down by an angry, ignorant mob who are so insecure that they can't handle simple mistakes being pointed out.

Oh, wait...

Re:"Clocks" (-1)

Anonymous Coward | more than 3 years ago | (#36562630)

that's because it's modernly acceptable for them to be interchangeable except to people who like to knitpick and point out mistakes

Re:"Clocks" (3, Funny)

gottabeme (590848) | more than 3 years ago | (#36562744)

The word you're looking for is "nitpick".

Re:"Clocks" (1)

MyFirstNameIsPaul (1552283) | more than 3 years ago | (#36562836)

Speaking of which, if you're really trying to help someone with these kinds of grammar issues, you should consider offering some easy ways to know when to use which version. 'Whom' is basically the same as 'him', while 'who' is basically the same as 'he'. By swapping in 'him' or 'he', most people can figure out which one is correct.

Re:"Clocks" (1)

praxis (19962) | more than 3 years ago | (#36562808)

According to the OED, it's been used for both nominative and dative direct and indirect objects for over a thousand years with varying degrees of acceptability.

Re:"Clocks" (1, Insightful)

Anonymous Coward | more than 3 years ago | (#36562716)

No, insisting on using "whom" is being an ass. Pointing out that even though it's unnecessary in all cases, in this case it is entirely incorrect, is the opposite of that.

It's a sad state of affairs when educated men get called down as "pedantic" when they deflate someone's ignorant pretentiousness.

Re:"Clocks" (1)

IonOtter (629215) | more than 3 years ago | (#36562226)

That is quite possibly one of the more useful Usenet postings I've seen in a very long time. Definitely good to know if you have a backup generator or two!

Re:"Clocks" (-1, Offtopic)

PopeRatzo (965947) | more than 3 years ago | (#36562240)

HVDC intertie

If you wear a condom, you won't get that.

You've got to wrap it before you tap it.

Re:"Clocks" (1)

radix07 (1889888) | more than 3 years ago | (#36562302)

Ummmm, this is not going to affect generator synchronization at all. These systems are dealing with much greater variances than what this small amount of tinkering is going to do to the grid. If they can't handle that, then there are going to bigger problems... Not saying that playing with the grid this way is exactly a great idea, but i doubt it is going to do much real harm.

Re:"Clocks" (1)

Ungrounded Lightning (62228) | more than 3 years ago | (#36562852)

Ummmm, this is not going to affect generator synchronization at all.

The point being made is that the claim that the east coast runs several cycles per day faster than the west coast is bogus. If they're interted without frequency conversion they don't slip cycles at all. The east coast might run with a phase shift. But if it slips a cycle this immediately precipitates the phase-thrash catastrophe that finished bringing down the east coast grid during the first "great northeast blackout".

If the US grid is cut up into several islands with automatic frequency-phase correction where they're tied together I'm unaware of it.

Re:"Clocks" (1)

petermgreen (876956) | more than 3 years ago | (#36562640)

Being out of sync is BAD but once you tie generators together they will keep each other in sync, so it's really only a concern when you first tie them together.

The thing is at the moment they play with the grid for no reason other than to keep the average number of cycles per second very close to 60 over a long period so clocks stay in sync, it sounds like they are planning to stop doing that.

Re:"Clocks" (3, Informative)

hawguy (1600213) | more than 3 years ago | (#36562666)

Clearly, whomever thought this was a Pretty Neat Idea hasn't read this:

http://yarchive.net/car/rv/generator_synchronization.html [yarchive.net]

and doesn't understand what happens when you're even a bunch of *degrees* out of sync, much less a few decihertz. We don't have *near* enough HVDC intertie to make this not matter, and I can't imaging how they think this is gonna work -- nothing at all on NERC's website to say what's *really* gonna happen, either.

Love all the warning, too.

I think the organization that's responsible for the reliability of the entire USA power grid has some idea of the need for frequency stabilization when connecting new power sources to the grid. Not that it's relevant for what they are proposing - power plants already know how to sync up their generators to the grid and they don't care if it's 60.001 Hz or 60.002 Hz, they'll take that into account.

The magnitude of this frequency deviation is tiny, 20 minutes/year is about .003% - the power grid can fluctuate much more than than on a daily basis, but until now, it's always been corrected to keep the overall frequency at 60 Hz.

Re:"Clocks" (4, Interesting)

John Hasler (414242) | more than 3 years ago | (#36562696)

Believe it or not, the engineers that operate the network actually know what they are doing.

The flow of power between tied AC networks is determined by phase, not voltage. To adjust the phase between your generator and that of a neighbor to whom you wish to send power you must run faster than he for long enough to accumulate the desired phase difference. Such adjustments are going on constantly throughout the network and conflict with the requirement to keep the average frequency at exactly 60Hz. Relaxing the latter requirement will make network operations easier and more reliable.

Re:"Clocks" (0)

Anonymous Coward | more than 3 years ago | (#36562884)

Somehow I think the people who run the power grid understand how generators are synced to the power grid better than an 11 year old usenet posting. The article seems to be talking about small corrections over a day to the 60hz signal.

Yes, the article isn't very specific, but it's a news article for general consumption, not an engineering white paper. If you have something more informative than an 11 year old usenet article that amounts to "power grid 101", please post it. Otherwise you're not telling anyone anything particularly interesting.

here's the scale (4, Informative)

Flyerman (1728812) | more than 3 years ago | (#36562088)

20 minutes fast over the course of a year.

Re:here's the scale (2)

isorox (205688) | more than 3 years ago | (#36562178)

20 minutes fast over the course of a year.

3 seconds a day. But twice a year people manually change the time due to summer time.

Re:here's the scale (3, Insightful)

toastar (573882) | more than 3 years ago | (#36562320)

3 seconds a day. But twice a year people manually change the time due to summer time.

Wait... You check the accuracy of the minutes when daylight savings comes rather then just hitting the +1 hour button?

Re:here's the scale (0)

Anonymous Coward | more than 3 years ago | (#36562372)

Yes I do. All clocks in my house tend to lose or gain a few minutes over 2-3 weeks.

Re:here's the scale (2)

blair1q (305137) | more than 3 years ago | (#36562376)

All of my clocks that matter synch themselves every few hours with the nearest WWV signal.

Many of my other timekeeping devices get their time hack from the net.

Anything free-running probably only has about a 30-second-per-day accuracy anyway (I don't own any Omegas, yet) and I really don't much care, because picking up a watch you haven't worn in a few months and setting it is part of the point of continuing to own analog technology at a time when I could put a solar-powered, radio-synchronized device on my wrist that will read accurately to the millisecond.

Re:here's the scale (1)

WidgetGuy (1233314) | more than 3 years ago | (#36562756)

Casio sells a nice radio-synchronized digital watch for $38USD. Got one a couple of years ago and I love it. Automatically adjusts itself for DST. I use it to set the clocks in my house that don't automatically adjust for DST (mostly those on kitchen appliances).

Re:here's the scale (1)

religious freak (1005821) | more than 3 years ago | (#36562856)

Not in Hawaii or Arizona :-)

Re:here's the scale (2)

CrimsonAvenger (580665) | more than 3 years ago | (#36562198)

20 minutes fast over the course of a year.

Well, that's one possibility.

Note that they also mention that if frequency averages "just over 60 cycles a second", then "clocks that rely on the grid will gain 14 seconds per day". Which is closer to 85 minutes per year than 20.

Assuming that 60.00 Hz gives you correct time, then you are gaining 14 seconds per day at 60.01 Hz.

Which means that 0.1 Hz difference from reference frequency translates to two-plus minutes per day, and about 14 HOURS per year error.

So, exactly how much frequency variation are they planning on allowing in this test?

Re:here's the scale (1)

Flyerman (1728812) | more than 3 years ago | (#36562354)

Yeah, there aren't a whole lot of specifics in TFA. Seems like some weak fear-mongering really.

Re:here's the scale (1)

VortexCortex (1117377) | more than 3 years ago | (#36562318)

Irrelevant. Once a day the $10 clock I purchased at the drug store wirelessly synchronizes itself to the radio time signal (WWVB) emitted by the U.S. Atomic Clock in Fort Collins, Colorado. I can't believe this feature isn't in every clock -- Oh well, live and learn.

My PCs (and servers) all synchronize clocks over the network time protocol (NTP) and are connected to uninterrupted power supplies (UPS) which regulate the voltage and Hz. I can't believe anyone still connects computers directly to wall outlet power -- Oh well, live and learn.

It's really too bad that the WWVB isn't broadcast with a cryptographic signature so that the time signal can not be pirated; Thus allowing public clocks to be updated to a time signal that is verifiability correct. I can't believe anyone still trusts data that isn't cryptographically signed -- Oh well, live and learn.

TL;DR: Only the reckless will be affected.

Re:here's the scale (2)

heypete (60671) | more than 3 years ago | (#36562412)

It's really too bad that the WWVB isn't broadcast with a cryptographic signature so that the time signal can not be pirated; Thus allowing public clocks to be updated to a time signal that is verifiability correct. I can't believe anyone still trusts data that isn't cryptographically signed -- Oh well, live and learn.

Personally, I'd like to see some WWVB-style relays, for better signal strength in buildings and other areas that don't normally get good signal (particularly during the day).

I know that some places use CDMA radio receivers as a time source for NTP servers, as CDMA signals can penetrate buildings better than GPS and the WWVB signal (it's particularly useful when one can't get roof access) and CDMA spec requires time to be in sync with a very small error (10 microseconds, if I recall correctly, but I'm quite possibly incorrect). Considering how small CDMA radios are, one should be able to make tiny CDMA receivers that get the time sync code from the cellular network.

Wow... (2)

jhoegl (638955) | more than 3 years ago | (#36562094)

Such a small change can have such a big impact.
I never really thought about how digital clocks keep track of time. This is a very interesting issue.
Of course, it could also turn into a boon for the industry, having everyone buy a clock that doesnt rely on "power timing".

Re:Wow... (1)

geekoid (135745) | more than 3 years ago | (#36562154)

If this messes up a digital clock, the clock was poorly engineered

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562252)

Or, it used a clock reference that was guaranteed to be within some tolerance. Not bad design, just the result of changing something that wasn't supposed to change, and has incredible consequences if it does change.

That's just silly to say it's poorly engineered.

Hehehe...captcha is "powering".

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562576)

No, poorly engineered is correct. I can't think of any good reason why this would be an issue with a clock besides poor engineering.

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562672)

Why do you say that???

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562274)

If not for relying on the counting the numbers of cycles in the power flow, how would you suggest that the clocks determine what length of time a second actually is? I doubt people would want to buy an atomic clock for their bedroom. I guess you could go to GPS, cellular or Internet syncing clocks, but they also can't be used in some situations (Indoors/Underground, outside of coverage area, no internet connection).

Re:Wow... (3, Insightful)

blair1q (305137) | more than 3 years ago | (#36562416)

Any clock with the word "quartz" associated with it is using a crystal timebase to determine how long a second, minute, hour, day, etc. are.

http://en.wikipedia.org/wiki/Quartz_clock#Accuracy [wikipedia.org]

Half a second per day, even if the power goes out and you're running off a battery, no matter if the mains frequency wobbles (which it's designed to do anyway).

http://en.wikipedia.org/wiki/Utility_frequency#Stability [wikipedia.org]

Re:Wow... (0)

geekoid (135745) | more than 3 years ago | (#36562770)

Did you even read your link?

A Crystal oscillator [wikipedia.org] takes in VOLTAGE to determine the signal.

http://www.zen22142.zen.co.uk/Circuits/Testgear/crystal.htm [zen.co.uk]

Re:Wow... (1)

Jello B. (950817) | more than 3 years ago | (#36562874)

RE: your signature. Tilde is already used to indicate a sing-song or playful voice. That's how it is. Sorry~

Re:Wow... (1)

h4rr4r (612664) | more than 3 years ago | (#36562436)

Even a $10 clock can get WWV time. Solved problem.

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562554)

Really? Quartz crystal [wikipedia.org] or even have it periodically sync with an atomic clock via RF [wikipedia.org] that your tax dollars are paying for [wikipedia.org] .

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562380)

Not really. That the clocks specification were written to take advantage of the correcting nature of the AC frequency. That frequency is much more accurate than you would on a normal $0.50 crystal oscillator could have. A crystal oscillator starts off with 100ppm of errors, have temperature coefficients and also changes frequency when it ages. That vs a well maintained line frequency by the government.

That accuracy part got thrown out, so we'll have more garbage in the landfill.

Re:Wow... (2)

heypete (60671) | more than 3 years ago | (#36562250)

Most digital clocks use a quartz oscillator as their frequency source. The mains power is not directly used for timing.

The only mains-powered clocks I've seen that use the power frequency as their frequency source tend to be older ones. Perhaps there's some modern ones that use it, but I've not seen any.

Re:Wow... (1)

jhoegl (638955) | more than 3 years ago | (#36562308)

Ah, so are these clocks based on motors then?
Such as an analog clock?

Re:Wow... (1)

heypete (60671) | more than 3 years ago | (#36562454)

My analog watch has a crystal oscillator that is used as a frequency source. The internals of the watch drive the watch hands with a very tiny motor.

I imagine a similar mechanism is used in mains-powered analog clocks, only with larger motors.

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562506)

WTF?

Motor?

It's quartz oscillator.

Google up for piezoeletric effect.

Analog clocks (2)

MillionthMonkey (240664) | more than 3 years ago | (#36562532)

When the public power grid was being established, a clock manufacturer petitioned successfully to have the mains time kept in perfect 60 Hz synchrony for clocks to keep time off of. This was viewed by everyone as a Big Win. After that, all you needed to make a clock was an AC motor; really nobody needed to actually bother with a real clock anymore except the people at the power station, so "the grid was the clock" the way "the network is the computer".

Re:Wow... (0)

Anonymous Coward | more than 3 years ago | (#36562840)

I had a digital alarm clock circa the late 90's that used the mains frequency for timing. These things run for ever, so there are probably millions of them out there in the wild. Most people who own them won't know how they work, and won't have any clue why they stop keeping time now. The only way I knew mine timed off the mains was because I was working on a ship, and the auxilliary generator wasn't precisely 60 Hz. It would drift several minutes a day when we went to the aux gen.

Re:Wow... (1)

Jonner (189691) | more than 3 years ago | (#36562704)

Such a small change can have such a big impact.

I never really thought about how digital clocks keep track of time. This is a very interesting issue.

Of course, it could also turn into a boon for the industry, having everyone buy a clock that doesnt rely on "power timing".

Every $2 watch has used a quartz crystal for decades. It's incredible that any electric clocks still use line frequency. If this change helps get rid of them, that's fine with me.

wtf are you green creeps doing now? (0)

Anonymous Coward | more than 3 years ago | (#36562096)

Whatever dubious 0.001% efficiency gain you claim you will get messing with the 60Hz cycle isn't worth it.

Re:wtf are you green creeps doing now? (0)

Anonymous Coward | more than 3 years ago | (#36562264)

FTFA:

Officials say they want to try this to make the power supply more reliable, save money and reduce what may be needless efforts. The test is tentatively set to start in mid-July, but that could change.

The bold text is the real reason. And "needless efforts" could also mean hiring less people to keep up the infrastructure and keeping the power relatively reliable.

Whenever a business, especially a large corporation, bitches and moans about "government regulation" or "EPA" or "litigation", you can be sure that they are obfuscating their desire to cheapen their product or service, blame someone else for increasing their prices and subsequently their margins, and generally trying to get sympathy from the general public while they screw them over.

American business' is out to fuck the American consumer not to enrich the stockholders, but to enrich management and their asshole buddies on Wall Street.

Is timekeeping really that difficult to solve? (0)

Anonymous Coward | more than 3 years ago | (#36562142)

Honest question. How hard/expensive is it to design an electronic timekeeping device that isn't directly based on electrical current? If the issue here is that some devices are poorly/cheaply made, it would seem, on the face of it, that these clocks should be designed better, rather than designing the electrical grid around the clocks. Bit of the tail wagging the dog?

Or is this just a straw man that the electric utilities want to put forward in order to accomplish a change that has a more insidious effect on consumers?

Re:Is timekeeping really that difficult to solve? (1)

sentientbeing (688713) | more than 3 years ago | (#36562246)

It looks like this method for timekeeping was common in the 1930s. I work in electronics and never in my life have I seen a clock that works like this. Ive been dismantling old equipment since I could hold a screwdiver. 35 years

Re:Is timekeeping really that difficult to solve? (1)

blair1q (305137) | more than 3 years ago | (#36562448)

You've seriously never seen a mechanical electric clock?

Re:Is timekeeping really that difficult to solve? (1)

hawguy (1600213) | more than 3 years ago | (#36562300)

Honest question. How hard/expensive is it to design an electronic timekeeping device that isn't directly based on electrical current? If the issue here is that some devices are poorly/cheaply made, it would seem, on the face of it, that these clocks should be designed better, rather than designing the electrical grid around the clocks. Bit of the tail wagging the dog?

Or is this just a straw man that the electric utilities want to put forward in order to accomplish a change that has a more insidious effect on consumers?

It's easy and relatively cheap to make new devices use their own time base, but there's a huge installed base of devices that do use powerline frequency because up until now, powerline frequency has been adjusted to keep it very close to 60 hertz. So it's not a matter of the tail wagging the dog - the grid intentionally guaranteed a stable time base so clockmakers took advantage of it. It's more like the dog decided that it doesn't want to wag the tail anymore so he's having it removed.

Re:Is timekeeping really that difficult to solve? (0)

Anonymous Coward | more than 3 years ago | (#36562384)

Very few actual clocks are based on the 60Hz AC cycle. It was more common long ago when accurate oscillators were expensive. Today good oscillators are very cheap; typically quartz crystals that produce signals accurate enough for basic time keeping.

Re:Is timekeeping really that difficult to solve? (1)

mark-t (151149) | more than 3 years ago | (#36562482)

It's not so much that electric grids are designed around clocks as much as it is that a good deal of electronic devices, including, most notably, alarm clocks, that use AC power have been designed around the the fact that household current frequency is extremely uniform, and has been so for many years.

I'd be willing to lay bets that when they start messing with this, they are going to find all kinds of devices they never imagined could be affected to start failing... some quite catastrophically (ie... it stops working altogether, components burning out or shorting, etc).

Greater Variation = Lower Quality (2, Insightful)

Anonymous Coward | more than 3 years ago | (#36562146)

"greater allowed variation in the frequency of the current carried on the U.S. electric grid"

This is marketing speak for lower quality electricity.

Time to start using the internet... (0)

Anonymous Coward | more than 3 years ago | (#36562152)

Hey, I've got 120 different clocks of my own.

analog wall clock,
thermostat,
coffee maker,
three alarm clocks in the bedroom,
microwave,
stove,
a clock in my van,

and they all show different times, some are already off by 20 minutes.

this is 2011, every one of these devices should be able to connect to the internet and synchronize time just like my PC does (should) so I can be on my merry little way.

I bought a z-wave thermostat thinking it would get it's time from the controller automagically, not the case. royally pisses me off.

Re:Time to start using the internet... (1)

hawguy (1600213) | more than 3 years ago | (#36562398)

Hey, I've got 120 different clocks of my own.

analog wall clock,
thermostat,
coffee maker,
three alarm clocks in the bedroom,
microwave,
stove,
a clock in my van,

and they all show different times, some are already off by 20 minutes.

this is 2011, every one of these devices should be able to connect to the internet and synchronize time just like my PC does (should) so I can be on my merry little way.

I bought a z-wave thermostat thinking it would get it's time from the controller automagically, not the case. royally pisses me off.

Do you really want to apply firmware upgrades to all of your devices everytime congress decides to change Daylight Savings time?

Would many people really take the time to program their wireless access point's WPA key into their coffee maker so it can sync the time?

Maybe extracting the time signal from Cellular GSM signals would be easier and nearly ubiquitous. Apparently the local cell phone tower knows what timezone I'm in, so there's be no need for devices to know, though I don't know how well that works on timezone borders.

Nevermind cheapo clocks (1)

istartedi (132515) | more than 3 years ago | (#36562192)

I'm much more concerned about my laptop power supply and the several hundred dollars I might have to shell out if this insanity fries my laptop. Ditto for the TV and the other appliances. The other appliances belong to the landlord; but it's still no fun to have to be around and have some tech service them.

Re:Nevermind cheapo clocks (3, Informative)

heypete (60671) | more than 3 years ago | (#36562282)

If your laptop power supply is anything like all the ones I've owned, it won't care. According to the label (and testing done while I travel), mine works just fine on nominally 50-60Hz mains power. I imagine it wouldn't really care if you went from 45-65Hz, though I suspect it might get a bit annoyed if you were to go to 400Hz or something extreme.

Re:Nevermind cheapo clocks (2)

IonOtter (629215) | more than 3 years ago | (#36562304)

When I was with the Military Sealift Command, all the "salty dogs" told me to invest, quite specifically, in a small UPS for my stateroom. They were quite adamant about never plugging your electronic gear straight into the outlets.

The first time I saw the overhead lights doing Saturday Night Fever, I was grateful for the advice. All my gear survived.

Re:Nevermind cheapo clocks (0)

Anonymous Coward | more than 3 years ago | (#36562782)

Most switching power supplies immediately convert ac power into dc with a simple bridge rectifier before running it through the switching transistor at a very high kilohertz before going through the power supplies transformer. you could run a switching power supply on just about any frequency and even dc power

Re:Nevermind cheapo clocks (1)

geekoid (135745) | more than 3 years ago | (#36562792)

Yes, but that's a different problem then this one; which is a tiny freq. drift.

Re:Nevermind cheapo clocks (2)

ls671 (1122017) | more than 3 years ago | (#36562358)

I would say you fears are unjustified, most laptop can run fine on 85 to 140 volts and from 50 Hz to 70 Hz while on grid power.

On the other hand, cheap alarm clocks rely on 60 HZ to keep time accurately, voltage may vary quite a bit without impact. They count 1 second at every 60 power inversion.

I have noticed that a very long time ago while working up north. We were on generator power and the generator often ran at 61 to 65 HZ and our cheap clocks would run out of sync.

Clocks with a crystal like computer or laptop clocks aren't affected.

 

Re:Nevermind cheapo clocks (2)

Miamicanes (730264) | more than 3 years ago | (#36562676)

> cheap alarm clocks rely on 60 HZ to keep time accurately

Um, I think you need to narrow that down to "cheap electromechanical alarm clocks", unless I've seriously overlooked something, "Cheap" alarm clocks (from China, in particular, as though the distinction even matters anymore) now basically consist of a backlit LCD module glued to a piece of plastic, with piezo buzzer for the alarm itself. The really, *really* hardcore-cheap ones don't even plug in -- they just ship with a coin cell, and aren't backlit (or make you press a button to light them up, like a 1970s wrist watch in reverse). The grand prize goes to one I saw ripped apart online that dispensed with the diode bridge, and wired up the sidelight LEDs to do double-duty as both nighttime illumination AND rectifiers. I vaguely remember seeing old-fashioned electric alarm clocks somewhere like Wal-Mart or Walgreens for a few bucks 5-10 years ago, but I think value-engineered LCD alarm clocks shoved them aside quite a while ago.

Re:Nevermind cheapo clocks (1)

ls671 (1122017) | more than 3 years ago | (#36562742)

> Um, I think you need to narrow that down to "cheap electromechanical alarm clocks"

Nope, as I stated in another post, I have several clocks in my home that rely on 60Hz to count 1 second. I have no electromechanical clock in my house, none.

http://it.slashdot.org/comments.pl?sid=2267902&cid=36562462 [slashdot.org]

surge protectors? (1)

KingAlanI (1270538) | more than 3 years ago | (#36562728)

do surge protectors do any good in this case? { I have a desktop system hooked up through one of those.}

Re:Nevermind cheapo clocks (1)

Jonner (189691) | more than 3 years ago | (#36562732)

I'm much more concerned about my laptop power supply and the several hundred dollars I might have to shell out if this insanity fries my laptop. Ditto for the TV and the other appliances. The other appliances belong to the landlord; but it's still no fun to have to be around and have some tech service them.

There's little risk of damage to any device because of the frequency changing slightly. The article didn't mention any expensive electronics because line frequency has no effect on them whatsoever. They all use DC internally, so their power supplies must rectify the line current anyway.

Re:Nevermind cheapo clocks (1)

Reziac (43301) | more than 3 years ago | (#36562766)

I'm wondering what happens to the electronic meter on my well pump, which already went mad once when the neighbouring pole got hit by lighting, and charged me an extra $100 for power I didn't use.

Not a serious problem (0)

Anonymous Coward | more than 3 years ago | (#36562232)

I doubt this will be a serious problem at all except for the few generator sources that are affected by environmental concerns (solar and wind)

Most thermal, cogeneration, and nuclear sources are pretty constant, and don't operate at exactly 60hz to begin with.

But here's why this won't be an issue... Since the mid-80's we've been using switching power supplies in our electronics, and as a nice side effect they work on 50/60hz, 110,120,125,220,240,250,etc volts. What will really be affected? Anything that doesn't have a switching power supply, like CFL and LED lights that don't tolerate dimming, and the piles of wallwarts that are nothing more than a transformer (no ic's.)

All that I really expect is that there will be an increase in people buying UPS equipment for their computers and home entertainment gear. Does anyone plug their gear only straight into the wall?

I think it's worth it (1)

BlueCoder (223005) | more than 3 years ago | (#36562256)

And it's only a test/phase in to see who complains. Only very old and cheap devices used power to clock themselves. If you really need those devices to be more accurate then they are easy to retrofit externally with a brick filter or internally change the mechanism to use a chrystal or replace in innards altogether.

Re:I think it's worth it (1)

blair1q (305137) | more than 3 years ago | (#36562472)

And it's only a test/phase in to see who complains.

I could have told them that: "Everyone who doesn't understand how things really work."

Re:I think it's worth it (0)

Anonymous Coward | more than 3 years ago | (#36562610)

[...] easy to retrofit externally with a brick filter or internally change the mechanism to use a chrystal or replace in innards altogether [...]

Easy for who and at what cost?

The external approach would generally be easy, but is going to have some bulk and therefore change the overall footprint of the device so could be slightly inconvenient for some situations and infeasible for a few situations. At a minimum, the power companies should provide such external devices to their customers for free (and replace them forever if they fail).

The internal approach is neither easy nor cheap for the average person. I've got a 30 year old clock radio I love -- not because of the sound quality (which is pretty weak), but because it has a great (brightness adjustable) display and wonderful UI. Instead of "hour/minute" up/down for setting the time or alarm, it's got a keypad with 0-9 on it so you just type in the time (or, the radio station frequency). Oh, and his/her alarm settings (re-purposed as "sucky morning meeting" and "normal developer hours" settings). I don't know if this uses the line frequency to keep synced, but I'll be really annoyed if it stops keeping accurate time if it does. Since there are probably a dozen of these things left in the world, there's not going to be an "authorized manufacturer approved internals upgrade for this" so I would have to pay someone to figure out the internals and design and implement a safe solution that fits in the form factor and get it UL approved (my lease requires I use only UL approved appliances). That ain't going to be cheap OR easy.

(Yes, I know there are some radios that have some of the same features -- such as some from C Crane -- but so far I've found none that have all.)

missing term. stupid post. (0)

Anonymous Coward | more than 3 years ago | (#36562270)

"20 minutes fast" implies a rate, but only specifies a quantity without a time. 20 minutes per WHAT DAMMIT?

Re:missing term. stupid post. (1)

hawguy (1600213) | more than 3 years ago | (#36562468)

From TFA:

The North American Electric Reliability Corp. runs the nation's interlocking web of transmission lines and power plants. A June 14 company presentation spelled out the potential effects of the change: East Coast clocks may run as much as 20 minutes fast over a year, but West Coast clocks are only likely to be off by 8 minutes. In Texas, it's only an expected speedup of 2 minutes.

My question is - will West Coast clocks run 8 minutes fast, or 8 minutes slow? My guess is that they'll be slow.

Electric clocks (4, Informative)

JohannesJ (952576) | more than 3 years ago | (#36562272)

Most clocks are not electric .Most Run on DC provided by a Crystal oscillator, the line frequency provided by the AC line to run them is irrelevant. only electromechanical electric clocks might be in error

Not just bad summarizing, bad reporting. (0)

Anonymous Coward | more than 3 years ago | (#36562276)

"Since 1930, electric clocks have kept time based on the rate of the electrical current that powers them."

So untrue. Maybe it was done that way in 1930. But not anymore.

Re:Not just bad summarizing, bad reporting. (1)

ls671 (1122017) | more than 3 years ago | (#36562462)

I still have quite a few clocks that work like this in my home. I mean which manufacturer is going to install a crystal in his device when he can get away with using the power source to count 1 second at every AC power inversion ?

You can test the clocks you own by plugging them into a cheap power inverter 12 volt DC to 110 AC that you can plug into the lighter plug in your car.

Get back to me when you are done. You should be surprised unless you specifically bought all the devices that have a clock in your home with that in mind.

Turntable strobe light (2)

DVega (211997) | more than 3 years ago | (#36562312)

Say goodbye to turntable strobe lights [flickr.com]

How big a deal? (1)

godel_56 (1287256) | more than 3 years ago | (#36562366)

Surely it can't be too difficult to apply a correction at about 3 am when the power load is very low?

Twenty minutes a year amounts to about 3.27 seconds a day.

forget about clocks (0)

Anonymous Coward | more than 3 years ago | (#36562402)

what happens when my spindle speed can vary by 10%? do i need to put a tach on my mill?

Re:forget about clocks (1)

hawguy (1600213) | more than 3 years ago | (#36562508)

what happens when my spindle speed can vary by 10%? do i need to put a tach on my mill?

If the powerline frequency deviated by 10%, many things would have problems... 20 minutes/year deviation is only around .003%.

power meter? (0)

Anonymous Coward | more than 3 years ago | (#36562430)

so does the power meter outside your house depend on this? if so, i can see my power bill jumping up with the frequency.

Re:power meter? (1)

ls671 (1122017) | more than 3 years ago | (#36562564)

The power meeter in your home should calculate electrons going back and forth in the wires, a.k. current.

If the period (cycle 60HZ) changes a bit it shouldn't affect your bill. On the other end, voltage variations might have more impact since electrons moving with less voltage carry less energy (Watts) and you are usually billed by KWh.

Of course in the end, it depends on the internal workings of your meter, there are different types.

Voltage already varies quite a bit so your meter is probably already quite inaccurate ;-)

Digital clocks and living overseas (1)

GodfatherofSoul (174979) | more than 3 years ago | (#36562450)

I learned this as an army brat when my dad was stationed in Italy. Firstly, you had to use these shoe box-sized heavy transformers (that were passed on as soldiers moved back stateside) to transform their 220v power to 120v. But, since they're on 50 hertz instead of 60 like here in the states, clocks would run apparently slower. I suppose I could've asked my parents for a new clock, but I learned how to calculate the time offset and would reset the time (not the alarm) for when I needed to get up.

Alarm Clocks (1)

Anonymous Cowar (1608865) | more than 3 years ago | (#36562456)

How many people pop right up at 0'dark thirty in the morning and start getting ready for school/work/drinking without any signal? Yeah, me neither. The alarm clock allowed for the suburbs by letting employees not have to cluster around public alarm clocks (church bells, factory whistles, etc). If my alarm clock is late, I'm late, if it's early, i lose precious moments in bed (not as bad as the first case, but still irksome).

I hope this gets swatted down on behalf of every person who has to wake up before dawn and doesn't rely on their cell phone to wake them up.

Besides, my Mr. Coffee machine is PFM (Pure effin magic) in that it has a warm, freshly brewed carafe of joe waiting for me every morning, if this grid experiment screws that up, I might just go on a pre-coffee shooting rampage.

Re:Alarm Clocks (1)

mark-t (151149) | more than 3 years ago | (#36562588)

How many people pop right up at 0'dark thirty in the morning and start getting ready for school/work/drinking without any signal?

Usually I can manage this very well. I have an alarm clock that functions as a backup in case I fail to wake up, but probably 9 times out of 10, I wake up on my own on within about 5 minutes of when the alarm would go off if I left it on. This happens even though there is a variance of up to 2 hours or so in the exact time I typically go to bed on a night before I am working.

The downside to this is that I also find it difficult to actually sleep in on days that I don't actually need to get out of bed, and would actually like to get some additional rest, unless I go to bed exceptionally late.

hmmm... reminds me of something... (0)

Anonymous Coward | more than 3 years ago | (#36562464)

Y2K.

The real question (3, Insightful)

thegarbz (1787294) | more than 3 years ago | (#36562500)

The real question is why do devices add the additional circuitry to count pulses off the mains grid rather than add additional circuitry to actually keep time?

A highly accurate crystal costs in the order for $1 for single quantities. A RTC $1-10 depending on feature set. If you already have a microcontroller you don't need the RTC either. Why are clocks etc reliant on an external signal to keep time? How do they keep time when they run on the battery which is a common backup for every $5 alarm you get?

As for streetlights ... Really? How is this not a system which gets timing from some other central authority. I don't know much about street lights, but is this something that will only affect old small town streetlights, or do the shiny new modern LED powered ones in the city act independently enough that they aren't capable of contacting an NTP server?

Re:The real question (2)

F.Ultra (1673484) | more than 3 years ago | (#36562538)

I guess that this is an US issue since you guys run a 60Hz grid, getting a correct sync from the European 50Hz is probably harder/more exensive than using a crystal because all the clocks that I have seen over here use quartz crystals to keep the time.

Re:The real question (1)

Anonymous Cowar (1608865) | more than 3 years ago | (#36562552)

I thought streetlights had solar sensors. I came to this conclusion when, near the ocean, i saw a particularly crap encrusted streetlight that was always on, regardless off how bright the sun was.

Re:The real question (1)

Anonymous Coward | more than 3 years ago | (#36562670)

Newer ones use solar sensors. There are probably some older ones that are on clocks somewhere. One controller would turn on a block or two's worth of lights. The controllers were programmed to come on at slightly different times to avoid a huge surge at 6PM or whatever. I haven't seen any like that for years but I haven't been looking, and I haven't lived in the Big City for almost as many years.

Generators can't stand that (1)

Anonymous Coward | more than 3 years ago | (#36562520)

Thirty years ago I worked for the local power company in one of their large coal fired stations. I can tell you that they hold very very very close to 60hz every single second. They really can't do anything else because every generator on the grid has to be at exactly the same phase at exactly the same time. Otherwise the power from one generator cancels out the power from another generator in a big plume of fire and smoke. Even being just a little bit behind the phase, which is called motoring, is very bad for some reason.

wow, really - popcorn time (0)

Anonymous Coward | more than 3 years ago | (#36562550)

If electrical generators aren't synced they blow up - big time.

Not going to effect me (0)

wulfmans (794904) | more than 3 years ago | (#36562586)

Jokes on them, I live off grid and make my own power.

Re:Not going to effect me (2)

Zorque (894011) | more than 3 years ago | (#36562854)

Cool, meanwhile this issue will potentially affect tens or hundreds of millions of people.

DAMMIT! (1)

The O Rly Factor (1977536) | more than 3 years ago | (#36562626)

Literally the same day as I find a beautiful 1960s era plug-in wall clock in a supply closet at work...one of the really nice ones with military time pained in red numerals and everything.

What about old analog tvs (1)

maxwells_deamon (221474) | more than 3 years ago | (#36562644)

I believe Older TVs use the 60 hz signal to sync. Some of this was changed and messed with when color came about. It would not surprise me to see some issues with some older analog TV''s

60hz (1)

p51d007 (656414) | more than 3 years ago | (#36562722)

I remember a couple of decades ago, you could buy surplus "atomic warning clocks" that would set off an alarm, if the country was under nuclear attack. The power companies would switch the time base from 60hz to 50hz, which is what the box was designed to trip on...that 10hz change. I don't think a lot of really critical things still use the AC line frequency for a time base, but I wouldn't want to take the chance.

We sell power (0)

Anonymous Coward | more than 3 years ago | (#36562786)

We don't sell time. If you want to buy time get a clock.

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