TWILIGHT SWITCH

      The unit consists of a photodiode, electronic control circuit and a relay. The photodiode is used to sense the ambient light. Photodiode resistance varies according to the ambient light intensity; this change in resistance is continuously monitoried by the electronic control circuit. During evening when the light intensity drops to a certain level the control circuit switches on a relay which is used to operate street lights, poarch lights etc. At dawn when the light intensity increase s the control circuit switches off the relay thus switching off the lights. as the unit works on a photodiode sensor it does not need any adjustments because of change in season.