In this project we show that how we interface the digital energy meter to the easy recharge unit and convert this meter into prepaid energy meter. By using this technique we show that how we convert all meter with the prepaid logic. When any concept is prepaid then there is a security of misuse of electricity uses. Normally in every postpaid connection bill is much higher then the prepaid. When there is postpaid, no body want t take care of the wastage, but at the end of month when bill is present then bill is paid by the house inchrage, small workers in the office, employees in the school, in all the private and govt office no body want to take care of the wastage. So we add some innovative idea to avoid and save this valuable energy for every one.
In this project we use one lcd screen. LCD screen display the balance amount every time, LCD screen not only show the balance amount but at the same time lcd display the unit consumption. When the balance is zero then output is off.
Now for continue the voltage we must need to recharge the unit from the mobile phone.
Circuit working:
Our project is to be divided into 6 parts.
- 5 VOLT REGULATED POER SUPPLY
- MOBILE SIGNAL DECODER
- BCD TO DECIMAL DECODER.
- MICROCONTROLLER INTERFACE.
- LCD INTERFACE .
- RELAY INTERFACE CIRCUIT
Componets used in this project.
LCD FOR DISPLAY PURPOSE DISPLAY THE BALANCE AMOUNT AND UNIT CONSUME ( 2 LINE AND 16 CHARACTER)
MICROCONTROLLER. 89C51, 40 PIN CONTROLLER, 128 BYTE RAM, 4 K BYTE RAM. USED HERE FOR LCD DISPLAY AND START STOP FUNCTION. CHECK THE BALANCE AND CONTROL THE LOAD AS PER THE BALANCE.
IC 8870 , DTMF DECODER IC.
IC 8870 PROVIDE A GSM INTERFACE WITH THIS CIRCUIT. DUE TO THIS IC WE DECODE THE CALL THE PROVIDE A BALANCE IN THE ENERGY METER AUTOMATICALLY.
IC 74154 IS A BCD TO DECIMAL DECODER ATTACH WITH THE MICROCONTROLLER TO INTERFACE WITH THE DTMF DECODER
5 VOLT REGULATED POWER SUPPLY TO PROVIDE A REGULATED VOLTAGE TO THE MICROCONTROLLER UNIT.
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In this project we will connect LCD at port 0. Which will show Units consumption and balance available. In GSM interface circuit we will use nokia mobile to interface with GSM detecting circuit. GSM interface circuit will be DTMF decoder IC. DTMF circuit will get input at pin2 of microcontroller.
5 VOLT REGULATED POWER SUPPLY CIRCUIT.
In this project firstly we use one step down transformer. Step down transformer step down the voltage from 220 volt Ac to 12 volt Ac. This Ac voltage is further converted into DC with the help of rectifier circuit. In rectifier circuit we use four diode. All the diodes are arranges as a bridge rectifier circuit. Output of this rectifier is pulsating Dc. To convert this pulsating DC into smooth dc we use one capacitor as a filter components. Capacitor converts the pulsating Dc into smooth DC with the help of its charging and discharging effect.
Output of the rectifier is now regulated with the help of IC regulator circuit. In this project we use positive voltage regulator circuit. Here we use three pin regulator. Output of this regulator is regulated voltage. If we use 7805 regulator then its means its is 5 volt regulator and if we use 7808 regulator then its means that it is 8 volt regulator circuit. In this project we use 5 volt dc regulated power supply for the complete circuit. Separate 9 volt dc power supply is used for the relay coil