Brooke, There are some interesting misconceptions here.
Yukon Power did not cause time to slow down. They did what every generating station does, which is to adjust drive power to make a synchronous power line clock match a precision reference clock. The tolerance is seconds because the means for controlling drive power has a time constant of several seconds. The real problem is the way demand varies. If you pour mechanical power into a generator, it will speed up when lightly loaded or slow down when heavily loaded. This is less of a problem when many generators are tied together by a power grid, as they are all synchronous machines. Central dispatching stations compare line and reference clocks, and direct plants with capacity to do so to make up lost cycles, or buy less from the most expensive sources when extra cycles are generated. If you have a 5 digit counter (or more) tied to a computer, you can plot the deviation of line frequency for 24 hour intervals. TVB had this on his site. What I saw in MN was that generators speeded up in the early morning to make up cycles so there was no reference error at 6 AM. Then the loads turned on and the cycles fell behind and recovered as power was dispatched, within +/- 6 seconds. This is good enough for social time, where the mundanes don't know about time-nuts. The Alaskan network is probably too sparse for central direction, so each power plant makes its own adjustments. Note that this doesn't necessarily produce stable control, ever. In this case, the reference clock appears to refer to GPS satellite time, but uses a standard wall clock to display it. It is the reference clock that slowed down when it should have failed to work at all. Perhaps the wall clock (maybe it was really a HP 113) needed oil. There's the real question for time nuts: How did the reference clock slow down? The first comment to the article shows what happens when your ego fails to shame you into silence when you don't know what you're talking about: "I don't understand how the amount being generated has anything to do with what happens to household electronics." [see above] "It would make more sense if the plant was generating at 55Hz versus 60Hz as some electronics will use the line frequency rather than integrated oscillators to set clocks." [The plant probably has breakers that take it off line when the frequency gets below 58 cycles, to keep it from dragging the network down.] [I thought that all electronics today converted the line to DC without sampling it, and ran timing from a crystal. Anyone know?] "Regardless, it shows YEC continues to be a bunch of bumbling oafs." [People who live in glass houses shouldn't stow thrones, or something like that.] Thanks, Brooke. I had some fun explaining all this. Bill Hawkins -----Original Message----- From: Brooke Clarke Sent: Thursday, April 08, 2010 12:58 PM To: Discussion of precise time and frequency measurement Subject: [time-nuts] Yukon Energy causes time sync problems Hi: http://whitehorsestar.com/archive/story/time-passed-more-slowly-over-the-eas ter-holiday/ -- Have Fun, Brooke Clarke http://www.PRC68.com _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
