Saturday 1 December 2012

Please Explain

When I woke on Thursday morning it was just getting light although the beautiful clear night when I went to bed had turned to custard and it was raining: a nuisance because I had a whirligig full of washing.  My bedside clock said 0550 which was a bit odd because the sun is usually well up by then but my sleepy mind just assumed it was the heavy cloud and I was back asleep in seconds.  In fact it was not until I woke and got up at 0750 (which is long after I'm usually up) and went through and put the television on for the news that I realised that my clock had had an electronic fit and was nearly 90 minutes fast. It's not just computers that can have fits.

I put it down as 'one of those inexplicable things' put the clock right and got on with things.  So imagine my surprise on Friday morning (yesterday) when the clock was again very fast.  Again I put it right.  When The Family came down for dinner last night Wendy and Martin mentioned that their clock had been 30 minutes fast yesterday morning and caused some surprise.  Both our clocks were fast again this morning.

The common factor with the fast clocks is that they are run off mains electricity.  All the other clocks were ok.

The utility company are replacing the main supply boxes at the moment and we are both on a temporary lorry-mounted generator.  Now I would have expected the utility company to ensure that the current supplied by the generator is exactly the same as the usual mains supply.

In any case I'm not sure how an alteration in current would make the clock run fast without causing damage to other electrical appliances.

Can anyone explain?

16 comments:

  1. Oooh! *hums X-Files tune* Spooky!
    No, I'm afraid I can't explain, but since you have identified the common factor I am sure that is the cause... somehow.

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    1. From later comments it looks as though it was/is Meike.

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  2. I suspect the gen set was running with low load. Ask Daz. We used to keep deck lights and anything we could on, on the low load gen set. Low load on an A.C. generator is really bad news for them. Windings run hot and resistance increases on one phase. The little devils can catch fire!
    Current surges should be a thing of the past. Thirty years ago I supervised a load of boffins (folk that could baffle me with bull shit). My job was to keep poking them with a sharp stick. They had a posh box that equalised the phases.
    No nowt about it but try going to bed and sleeping in an orderly and synchronised fashion. Leave the telly on and every light, a couple of 2KW fires. Listen to the gen set you'll hear it come on load.
    Couple of nights of this and you will be sleeping through lunch.
    That's my best shot. If that doesn't work get a wind up clock movement.
    Have fun. Let us know how you get on.
    PS. Unplug the computer....Lap tops should be okay.

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    1. We still have the generator and we still have the fast clocks. Fortunately, Adrian, I don't have a PC any more. In fact laptops seem to be taking over everywhere.

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  3. Sounds like you've got a Devil in the Belfry... You'll have to change the name of where you live to Vondervotteimittiss. Maybe Adrian knows what he's talking about - to me his story makes just about as much sense as Edgar Allan Poe's (i.e. I get the feeling I don't understand a word...)

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    1. I didn't know that Poe story Monica (in fact although I have his collected works I don't know many of his stories). I have enough problems just saying it!

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    2. I happen to have this story in a thin volume of selected Poe stories which I've had since childhood - in Swedish translation, and in Swedish it has a different title, which is also the title of that whole collection: When the clock struck thirteen. So that title was really all I remembered and which popped up when I read your post. I had to go back to the book and read the story to recall the actual content of it. And then look it up on the internet in English. Ah well - a bit of education for us all! (I bet I did not "get" the name of the town the first time I read it, back when I first got the book. I'm not sure even the translator of the story did, as they left it un-translated.)

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    3. Many years ago (and I'm sure you must know this story of mine, Monica) I had an epiphaic (OK I know that I've just made the word up) moment when I realised that the odd German word used as a default password for the Sage computer program was not actually Letmein but 'let me in'. So, not having worked out the meaning of Vondervotteimittiss I set about applying the Letmein principle to it. I've now had another epiphany. That may be worth a post all of its own Monica.

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  4. No explanation here, but it must be of some comfort to know you are not the only one running fast!

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    1. At least, Lisa, I know I don't have to go out and get a new bedside clock.

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  5. I'm guessing that the AC frequency is too high and the clock is synchronized with the mains power frequency. For example, if the clock assumes a power supply of 50Hz (which is the New Zealand standard) then it would simple count to 50 then add a second. Now if the power from the generator is at 60Hz, it would still count to 50 before adding a second but it would do this 1/6 of a second too soon and it doesn't take too long for 1/6 of a second per second to add up to a real observable time difference.

    Relying on the "clock cycle" used to be a common way of adding pauses to computer programmes. Rather than watching the time you'd simply count up to a large number, knowing that adding 1 and checking the result ate up a number of clock cycles. This was fine when you ran the programme on identical hardware, but as soon as we moved to PCs with ever increasing processor speeds, what used to be a pause of seconds might now disappear in the blink of an eye.

    Better hardware should really have some form of oscillating crystal for keeping time, which I wouldn't expect to suffer from a slight change in AC frequency. I'm guessing your cooker clock is probably showing the right time, as will your hi-fi etc. as they will have better electronics than a bedside alarm clock. I'm not sure what other signs you would see if this is the problem although I guess lights and power adaptors might run a little hotter than normal.

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    1. Thanks Mark. Is there no end to your knowledge? Although I suppose this is essential to your knowledge of computers so there is a link. It was a fascinating read though.

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  6. A bit of a gen set problem is the least of the Kiwi's problems....about time they concentrated on playing rugby.
    I still can't believe that England are capable of giving them a good seeing to.

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    1. Dangerous talk Adrian. That might have been England's Last Chance!

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  7. GB, you have a great internal clock, so no need for the other one that is acting up at all.
    Hope your main supply boxes have been replaced and the clock has settled back down for your sake.
    At first I thought maybe you had one of those satellite clocks which adjusts time on its own, and can be a real problem, especially in a time zone like mine where there is no time change, not even for DST.

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    1. We went back onto the mains supply this evening Virginia so it will be interesting to see what the clock says in the morning. I've just put it right.

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