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Economy 7 Time Clocks 40/50 years ago...

AncientMariner
To help resolve a query in the Ask The Community Forum, why did the time clock for Economy 7 and similar supplies with two meters and  a full load time clock switch (no contactor), tick?

Were they an auto-rewind clockwork time clock so as to keep in time during/following a power cut?

Clive

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    I believe that some early ones were 'spring reserve' - i.e. a motor drove a spring, which in turn drove a conventional clockwork mechanism - as you say to save the 'Boards having to go around re-setting all the clocks after a power cut.


    Later ones were I suspect quartz with a battery backup - but still having an analogue mechanism these will likely 'tick' too as the electronics pulse the drive to the clockwork.


      - Andy.
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    I believe that some early ones were 'spring reserve' - i.e. a motor drove a spring, which in turn drove a conventional clockwork mechanism - as you say to save the 'Boards having to go around re-setting all the clocks after a power cut.


    Later ones were I suspect quartz with a battery backup - but still having an analogue mechanism these will likely 'tick' too as the electronics pulse the drive to the clockwork.


      - Andy.
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