Light-controlled street lamp switch usually consists of photosensitive element, comparator, control circuit and relay. Photosensitive elements generally use photoresistors, photoresistors or phototransistors, which can change the resistance or current according to the change of light intensity. The comparator is used to compare the electrical signal output by the photosensitive element with a set threshold and judge whether the light intensity exceeds the set threshold. The control circuit controls the switch state of the relay according to the output signal of the comparator, so as to control the switch of the street lamp.
When the light intensity is lower than the set threshold, the electrical signal output by the photosensitive element is small, the comparator judges that the light is insufficient, and the control circuit closes the relay to turn on the street lamp. When the light intensity is higher than the set threshold, the electrical signal output by the photosensitive element is larger, the comparator judges that the light is sufficient, and the control circuit turns off the relay and turns off the street lamp.
The principle of light-controlled street lamp switch is based on the sensing ability of photosensitive elements to light intensity, and the automatic control of street lamp switch is realized through the synergistic effect of comparator and control circuit. This switching principle has the advantages of energy saving, environmental protection and intelligence. It can automatically adjust the brightness of street lamps according to actual needs, improve the use efficiency of street lamps and reduce energy waste. It is widely used in modern urban lighting system, providing people with a more convenient, comfortable and safe living environment.