mICRO Minds: Real Time Clock based Industrial Automation (Energy Saver) using Dallas RTC and I2C protocol

Abstract:

Advertising hoardings, commercial sign boards, and street lights are generally switched on at 6:30 pm and switched off at 10:00 am because nobody is available at the place in the morning to switch it off. But actual required time is 6:30pm to 11:30pm and 4:30am to 6:30am. Meantime i.e., from 11:30pm to 4:30am is not required, because the public flow on the roads is almost nil in this time. And from 6:30am to 10:00am is also not required as the sun light is available during this time. That means every day around nine hours of power is wasted. This project gives the best solution for electrical energy wastage. Also the manual operation of the lighting system is completely eliminated.

The Project AT89S8252 Microcontroller Based Energy saver for Commercial Lighting system with RTC DS1307 Interfacing is an interesting project which uses AT89S8252 microcontroller as its brain. This project is very useful for commercial sign boards, advertising boards, street lights for automation lighting system. This system switches on the lights only at preprogrammed timings. As the DS1307 Real Time Clock chip with battery back-up is used, there will be no disturbances for the programmed on/off timings even in power failures.

3X4 keypad is provided for entering the required timings. This keypad made this project user friendly. 4-digit seven segment display is provided to display the alarm times and current time. DS1307 is interfaced to the microcontroller for real timing performance. A 3V battery can be connected to DS1307 to avoid time disturbances caused by power failures.

AT89S8252 has inbuilt flash EPROM. Data stored remains in the memory even after power failure, as the memory ensures reading of the latest saved settings by the micro controller. It can retain data for more than ten years.

This project uses regulated 5V, 500mA power supply. Unregulated 12V DC is used for relay. 7805 three terminal voltage regulator is used for voltage regulation. Bridge type full wave rectifier is used to rectify the ac out put of secondary of 230/12V step down transformer.