The project is designed for reading electrical energy consumed in units and in rupees to display on an LCD screen to the user. This data is also provided to the electrical department using GSM technology for billing purposes. Owing to high electricity cost these days it becomes necessary for the consumer to know as to how much electricity is consumed to control electricity bill within his budget by recharging the energy meter units via S.M.S .
Finally when the energy meter coming to zero user can again recharge according to the purpose used. In this proposed system, the consumer will get his energy consumption data on real time basis on a LCD display. The same data is sent through GSM modem to the electricity department via SMS. A microcontroller of 8051 family is interfaced to the energy meter to get the Watt Hour pulses.
Further this project can be enhanced by to control the electrical appliances remotely via SMS. Also, the electricity department can send the monthly bill amount over SMS to the receiving unit for consumer information.
GSM BASED PREPAID ENERGY
METER BILLING VIA SMS
CH. RAJASEKHARA REDDY M.Tech,
T.SRINIVASA REDDY (10MH1A04B3)
M.N.S.RAVI TEJA (10MH1A0489)
P.CHARAN TEJA (10MH1A04A5)
The main objective of the project is to develop a
prepaid energy meter.
The microcontroller takes the reading from the energy
meter and displays the reading on the LCD. The reading
of the energy meter is also sent to the cell phone of the
user by a message through GSM modem.
This project is powered by an on-board power supply
takes the ac power and converts it into dc power that is
fed to on-board devices and integrated circuits.
• An energy or electric meter is a device that measures the
amount of electrical energy consumed by a residence,
business, or an electrically-powered device.
• Electric meters are typically calibrated in billing units, the
most common one being the kilowatt hour.
• It is a smaller computer
• Has on-chip RAM, ROM, I/O ports...
A single chip
Features of AT89S51/52:
Compatible with MCS®-51 Products
8K Bytes of In-System Programmable (ISP) Flash Memory
Endurance: 10,000 Write/Erase Cycles
4.0V to 5.5V Operating Range
Fully Static Operation: 0 Hz to 33 MHz
256 x 8-bit Internal RAM
32 Programmable I/O Lines
Three 16-bit Timer/Counters
Full Duplex UART Serial Channel
Interrupt Recovery from Power-down Mode
Dual Data Pointer
PIN DIAGRAM OF AT89S51:
• 40 Pin IC
• 4 Ports
• 32 Programmable I/O Lines
230 V AC
12V step down
• used for all long-haul communication
• Cables that carry serial data
• RS232 carries serial data in between micro controller
and MODEM through DB9 connector
The MAX232 is an integrated circuit that converts signals from
an RS-232serial port to signals suitable for use in TTL
compatible digital logic circuits.
The MAX232 is a dual driver/receiver and typically converts
the RX, TX, CTS and RTS signals .
When a MAX232 IC receives a TTL level
to convert, it changes a TTL Logic 0 to
between +3 and +15V, and changes TTL
Logic 1 to between -3 to -15V, and vice
versa for converting from RS232 to TTL.
• The DB9 (originally DE-9) connector is an analog 9-
pin plug of the D-Sub miniature connector family (D-
Sub or Sub-D).
A relay is an electrically operated switch. Many relays
use an electromagnet to mechanically operate a switch,
but other operating principles are also used, such
as solid-state relays.
Relays are used where it is necessary to control a circuit
by a low-power signal (with complete electrical isolation
between control and controlled circuits), or where
several circuits must be controlled by one signal.
Relays with calibrated operating characteristics and
sometimes multiple operating coils are used to protect
electrical circuits from overload or faults
The term GSM usually means the GSM standard
and protocols in the frequency spectrum around
The MS is the physical equipment used by a
subscriber, most often a normal hand-held cellular
Base transceiver station:
The BTS comprises the radio transmission and
reception devices, and also manages the signal
processing related to the air interface.
A GSM modem is a specialized type of modem which accepts a SIM
card, and operates over a subscription to a mobile operator, just like a
From the mobile operator perspective, a GSM modem looks just like
a mobile phone.
When a GSM modem is connected to a computer, this allows the
computer to use the GSM modem to communicate over the mobile
While these GSM modems are most frequently used to provide
mobile internet connectivity, many of them can also be used for
sending and receiving SMS and
An IR LED, also known as IR transmitter, is a special purpose
LED that transmits infrared rays in the range of 760 nm
The appearance is same as a common LED. Since the human eye
cannot see the infrared radiations.
The camera can show us the IR rays being emanated from the IR
LED in a circuit.
LIQUID CRYSTAL DISPLAY (LCD):
Most common LCDs connected to the microcontrollers are 16x2
and 20x2 displays.
This means 16 characters per line by 2 lines and 20 characters per
line by 2 lines, respectively.
If an 8-bit data bus is used the LCD will require 11 data lines
(3 control lines plus the 8 lines for the data bus)
The three control lines are referred to as EN, RS, and RW
EN=Enable (used to tell the LCD that you are sending it data)
RS=Register Select (When RS is low (0), data is treated as a command)
(When RS is High(1), data being sent is text data )
R/W=Read/Write (When RW is low (0), the data written to the LCD)
(When RW is high (1), the data reading to the LCD)
Keil an ARM Company makes C compilers, macro assemblers,
real-time kernels, debuggers, simulators, integrated environments,
evaluation boards, and emulators for ARM7/ARM9/Cortex-M3,
XC16x/C16x/ST10, 251, and 8051 MCU families.
Compilers are programs used to convert a High Level Language
to object code. Desktop compilers produce an output object code for
the underlying microprocessor, but not for other microprocessors
AT commands are instructions used to control a modem.
AT is the abbreviation of Attention. Every command line starts with
"AT" or "at". That's the reason, modem commands are called AT
Many of the commands that are used to control wired dial-up
modems, such as ATD (Dial), ATA (Answer) supported by MODEM.
Besides this common AT command set, GSM modems and
mobile phones support an AT command set that is specific to the GSM
technology, which includes SMS-related commands like AT+CMGS
(Send SMS message), AT+CMSS (Send SMS message from storage),
AT+CMGL (List SMS messages) and AT+CMGR (Read SMS
• Using this project we can reduce the manual
Efforts to take the readings from the energy
Meter which is cost effective solution .
• Reduces man power.
• It is user friendly and we can enhance this
Project ,in which an electricity department can
Send message to the consumer about the