Astronomical time switch for switching on street lights, advertisement hoarding lights, sign board lights at sunset time & switching off at sunrise time without any light sensor. Sunset & sunrise time is generated every day by microcontroller based astronomical time switch using astronomic software for any geographic location [latitude, longitude & time-zone]. With twilight setting lights can be switched on earlier from sunset time [for indoor lights] or delayed from sunset time [for outdoor lights] by 0 to 60 minutes, similarly switch off will be delayed [for indoor lights] or earlier [for outdoor lights] than sunrise time. To save electrical power, partial lights can be switched off at any set time late night after sunset, if required can be switched on again early morning at any set time before sunrise. If 2kw of light load is switched off for 6 hours every night, it can save 360 units of electrical power every month. Municipal, city corporation can use it for street lights. Industries, commercial establishment & housing societies can use it for compound & other lights. In case of power failure set parameters are saved in memory & clock runs on internal battery.
