Patent attributes
A time-controlled security lighting system records the length of nighttime and is capable of automatically adjusting for seasonal nighttime hours. The time duration between the initial nighttime darkness and the light of dawn, as sensed from the prior day by a photocell, is measured and recorded in memory. As the surrounding area becomes dark, the lighting system is activated to provide the illumination for the area. The duration of illumination is determined based on a predetermined fraction of the recorded length of nighttime from the previous night. The control system can adjust the duration of illumination according the recorded nighttime durations from the previous night. The control system can also adjust the level of illumination based on the signals from a motion detector, where the lights are set at a higher brightness for a predetermined amount of time upon detection of motion.