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dennis@home dennis@home is offline
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Default Decent priced proper dusk-dawn time switches



"Dave Plowman (News)" wrote in message
...
In article ,
Owain wrote:
dennis@home wrote:
I like the way it says it can be left unattended for years.. then
states an accuracy of 5 mins per year. How far out does it need to be
before it needs attending to?


If it loses 5 mins in the first year then gains 5 mins in the second and
third years, then loses 5 mins in the fourth year, it'll never be more
than 5 mins out.


That's probably a lot less than the natural variation of twilight due to
local weather conditions .


I'd imagine it uses a synchronous motor so isn't actually losing time. It
just can't adjust for the variations of the solar cycle year on year.


That makes it worse doesn't it?


Anyway toolstation item #44224 looks like a simple solution.
LE buld with built in dusk to dawn sensor so you throw it away with the
lamp.