In Automatic Street light control project for on & off using light dependent resistor, we developed an automatic energy efficient device using micro controller based on light dependent resistor.
In recent day’s energy efficient control systems are gaining importance due to the implementation of embedded systems in the field of automation technologies, the key elements of the embedded systems are micro controllers.
Need of automatic sensing devices:
- To conserve the wastage of electricity.
- Limiting usage of power in unnecessary time.
- To maintain accurate intervals of time in switching street lights.
Youtube video link to view block diagram, circuit diagram, components list.
The streets are automatically switched on when the light intensity falls below the threshold value, and the intensity of the light is sensed by the light sensors i.e. light dependent resistors, light dependent resistor exhibits high resistance under sufficient light and acts as an conductor i.e. low resistance path in times of low light intensity periods. This entire process is monitored by a micro controller based on the signals from the light dependent resistor.
- Micro controller – low power high performance 18F452 Microcontroller is used in the project which manipulates the circuit based on the light dependent resistor.
- Power supply circuit – a combination of step down transformer, bridge rectifier, filter, regulator used for getting 5v regulated dc output.
- Display unit – 16×2 LCD modules is used in this project as an output device.
- Triggering circuit – relays are used at the output terminals of the micro controller in order perform the on/off operations for the circuit.