Timer switch responsive to solar cycle for e.g. house lights - has switching point arranged in fixed relationship to sunrise or sun-set

摘要

The switch exhibits switching points which have a fixed time relationship to the position of the sun. This relationship between the switching points and the sun's position is manually selected via an input device which retains the selected setting even if the current supply is interrupted. Pref. the timer switch has a radio clock receiving time and date information, which is fed to a microprocessor system containing a programme for calculating sunrise and/or sunset for each day of the year. When the sunrise or sunset time has been calculated the required switching time is added to or subtracted from it and the result is stored for continuous comparison with the actual time, until the two agree, when the switching is initiated. The timer may control house lights or window blinds.