First, we need to install a photosensitive sensor to detect the intensity of the surrounding light. The photosensitive sensor converts the light intensity into an electrical signal, which is input into PLC for processing.
Secondly, we need to set a time controller to set the switching time of street lamps. PLC can automatically control the switch of street lamp according to the setting of time controller.
In PLC, we can write simple programs to realize the automatic control of street lamps. The logic of the program is as follows:
1. Read the input signal of the photosensitive sensor to obtain the current ambient light intensity.
2. Judge whether the current time is within the set lighting time range. If yes, execute the next step; If not, turn off the street lamp.
3. Judge whether the current ambient light intensity is lower than the set threshold. If yes, turn on the street lamp; If not, turn off the street lamp.
4. Cycle the above steps to realize real-time automatic control of street lamps.
Through the programming of PLC, the switching time and light intensity threshold of street lamps can be adjusted according to actual needs to adapt to different environments and energy-saving requirements.
To sum up, using PLC to automatically control street lamps can improve the energy utilization efficiency of street lamps, reduce the workload of manual operation, and can be flexibly adjusted according to actual needs. This automatic control system can be widely used in urban roads, parks, squares and other places to provide people with a safer and more comfortable night environment.