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On Tue, 25 Jun 2024 08:56:17 -0500, "Michael F. Stemper"Functionally, there is no difference between a timer that works by
<michael.stemper@gmail.com> wrote:
On 20/06/2024 11.21, Paul S Person wrote:Three things:On Thu, 20 Jun 2024 02:59:25 GMT, Random <random@who.cares> wrote:>>A conventional bulb's filament is not sensitive to AC voltage fluctionations,>
where the conversion electronics is. My guess is that your wiring to that
light is causing voltage dips and is stressing the electronics in the LED bulb
base.
I've seen a similar claim about timers that actually count
cycles-per-second: if those vary then the timer misperforms.
This isn't really an issue in North America. According to NERC[1], frequency in
the Eastern Interconnection (EI) is above 59.972 Hz 95% of the time. This is
99.95% of nominal frequency, or an error of 28 mHz.
>
If frequency sat that low for a 24 hour period (which it doesn't; frequency error
regularly crosses zero), it would be a loss of 40 seconds in a day.
>
As a matter of fact, a few years back, the EI had an ongoing problem with frequency
being high: 3 mHz fast as a sustained average over several years. This was considered
a significant enough issue to require an investigation[2].
>
If uncorrected, it would have caused clocks to gain over 4 seconds per day. This
led to regularly implementing Time Error Correction. In this case, that meant a
coordinated (across the EI) reduction in generation to reduce frequency until the
time error crossed zero again.
>
Four seconds error per day is considered a problem. If you live in North America,
you can count[3] on your analog clock.
-- I was talking about a timer, not a clock. In particular, a timer
controlling our porch light, when went wonky after about 10 years. It
could, of course, have simply aged out, or my switch to CFLs may have
been responsible, who can say? And the timer was put in in the 90s.
Still works fine as manual switch, though.
-- My memory is that our City Light was reducing the CPS deliberatelySeattle City Light can not let their frequency vary independently, unless
-- or allowing it to fluctuate as it chose -- for some reason.
-- Seattle is not in the Eastern Interconnection. Not that I thinkThat'd be the Western Interconnection (WI), run by the Western Electricity
whatever Interconnection it /is/ in does any different than the EI.
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