International Conference on Computing and Control Engineering (ICCCE 2012), 12 & 13 April, 2012

ISBN 978-1-4675-2248-9 © 2012 Published by Coimbatore Institute of Information Technology

Abstract—The billing process of electricity consumption

which we are using at present is very long process and

requires lot of man power. For overcoming all the

difficulties present in this system we are introducing fully

automated billing process. In the proposed system front end

is user friendly and can be operated easily by having

minimum computer knowledge. Two GSM modems are

used one connected to electric meter and another connected

to PC present in office of electricity board. The PC is the

computer which consists of all database such as meter

reading, bill amount, due amount, last date for bill

payment.GSM modems consists of SIM cards possessing

unique number. User interface consists of LCD which

displays the power consumed and amount of bill to be paid.

User also consists of a mobile phone through which bill

details can be communicated to the consumer. Bill can be

paid just by recharging through the mobile.

Keywords---GSM, Microcontroller, Embedded

Algorithm, intelligent metering.

I. INTRODUCTION

From many years, the electric power systems had

undergone negligible changes in their operating conditions

and the equipment employed for their control and

monitoring. Many attempts have been made to design the

energy meter with instant billing but till now the designed

energy meters did not give any replacement for the system

where the user has to connect the recharge card to

recharging unit, and then the units will be loaded into

recharge card.

In this proposed work we are implementing a prepaid

electricity meter connected to electricity office interface

through GSM network. When we use the electricity the

amount which we had used is calculated by energy meter at

user interface. This information is passed to microcontroller.

Here we use 8051 microcontroller programmed with

embedded C language. This controller decodes the

information given by the electric meter and transmits the

information to LCD module and GSM modem.GSM modem

consists of a SIM card possessing unique number that

transmits the information to electricity board which again

consists of a GSM modem connected to a PC. The

information from the modem is decoded and data base in the

PC is updated. This updated information is sent to user

mobile. Now by just recharging this mobile the bill amount

can be settled. A conformation message is sent to mobile

about the bill settlement .The whole process is done

automatically without any manual involvement hence the

probability of occurrence of error is negligible.

Dr.T. Vigneswaran, SG, SRM University.

M. Srikarthik, UG, SRM University.

S. Altamash, UG, SRM University

The importance of proposed work can be well understood

if we keep in mind the amount of electricity being stolen

every day. As a user can get his or her bill at any instant and

can even pay it at any instant, so any kind of misuse by any

other person can be avoided.

The organization of the paper is as follows: In section

2, we discuss the proposed design that also presents module

description for our proposed system. Detailed circuit

analysis description is provided for each block used in this

section. In section 3, we present the software

implementation along with algorithm and flow diagram. In

section 4, PCB designing, actual circuit implementation is

shown. Finally, some conclusions are offered in section 5

II. PROPOSED WORK

The old electromechanical induction meters are being

replaced by more modern electronic instruments, which are

more suitable for implementing modern tariff policies, such

as different hourly tariffs. In the proposed work, the micro

controller & the GSM unit is interfaced with the Energy

meter of each house. Every house has a separate number,

which is given by the corresponding authority. One GSM

modem is present at the consumer side and another at

electricity board office.

A. Isolation and Relay Circuit

The microcontroller provides the power of only 5V,

whereas the voltage required to operate the valve is 12V. So

to solve this problem we use an isolation and relay circuit.

The power to operate the valve is derived from the power

supply module and then the signal is derived from the

microcontroller as shown in Figure.

As in the figure isolation and relay circuit consists of a

valve which is connected to collector transistor for which

emitter is given a 120V DC supply base of the transistor is

connected to collector of another transistor U4 through a

470 ohm resistance.

B. Interfacing with the GSM Module

GSM introduction

Global system for mobile communication is globally

accepted standard for digital cellular communication.GSM

is the name of standardization group established in 1982 to

create a common European mobile telephone standard that

MODERN ELECTRICITY BILLING SYSTEM

USING GSM Dr.T. Vigneswaran, M. Srikarthik and S. Altamash

International Conference on Computing and Control Engineering (ICCCE 2012), 12 & 13 April, 2012

ISBN 978-1-4675-2248-9 © 2012 Published by Coimbatore Institute of Information Technology

would formulate specifications for a pan_Europeon mobile

cellular radio system operating at 900MHz

Interfacing GSM module

The microcontroller output is not compatible with the

GSM module. To make it compatible we require the DB9

Connector and the MAX 232 connector. This will enable the

microcontroller to send a message to a predefined phone

number. Here MAX232 acts as driver which converts TTL

levels to RS232 levels. For serial interference GSM modem

requires the signal based on RS232 levels. The T1_OUT and

R1_IN pin of MAX232 is connected to the TX and RX pin

of GSM modem.

C.LCD Interface with Microcontroller

Introduction

An HD44780 Character LCD is an industry standard

liquid crystal display (LCD) display device designed for

interfacing with embedded electronics. These screens come

in common configurations of 8x1 characters, 16x2, and

20x4 among others. The largest such configuration is 40x4

characters, but these are rare and are actually two separate

20x4 screens seamlessly joined together.

The most commonly used LCDs found in the market

today are 1 Line, 2 Line or 4 Line LCDs which have only

one controller and support at most 80 characters, whereas

LCDs supporting more than 80 characters make use of 2

HD44780 controllers. Apart from displaying some simple

static characters you can create animated text scripts and a

lot more!

LCD in proposed system

The system also consists of a display system having a

LED and an alarm system. When the meter is working LED

glows when GSM module sends the message. The buzzer

will also buzz indicating the message is sent or received.

LCD module has 8-bit data interface and control pins as

shown in Figure 3. One can send data as 8-bit or in pair of

two 4-bit nibbles. To display any character on LCD micro

controller has to send its ASCII value to the data bus of

LCD. For e.g. to display 'AB' microcontroller has to send

two hex bytes 41h and 42h respectively. LCD display used

here is having 16x2 sizes. It means 2 lines each with 16

characters.

In our proposed system we can find power usage

instantaneously through the readings of this LCD.As we are

using prepaid system this very useful to know when to

recharge and how many units still left for usage.

D. Embedded Processor

In the proposed work, the power consumption circuit and

GSM module are interfaced through the ports of standard

microcontroller AT89C52. The AT89C52 is a low power,

high performance CMOS 8-bit microcomputer with 8K

bytes of Flash programmable and erasable read only

memory (PEROM). The device is manufactured using

Atmel’s high density non-volatile memory technology and is

compatible with the industry-standard 80C51 and 80C52

instruction set and pin-out. The processor Flash allows the

program memory to be reprogrammed in-system or by a

conventional non-volatile memory programmer. By

combining a versatile 8-bit CPU with Flash on a monolithic

chip and Atmel AT89C52 is a powerful microcomputer

which provides a highly-flexible and low cost solution to

many embedded control applications. The AT89C52

provides the following standard features: 8K bytes of Flash,

256 bytes of RAM, 32 I/O lines, three 16-bit timer/counter,

a six-vector two-level interrupt architecture, full-duplex

serial port, on-chip oscillator and clock circuitry. The

extension of ports can be done by using 8255 standard PPI.

Here we programme 8051 microcontroller with embedded

C language .This 8051 module is interfaced with GSM

modem, LCD module, EB meter, load e. t. c. As already

mentioned the billing system is an prepaid system. When

power is being consumed the readings got noted by EB

meter and displayed by LCD. When maximum consumption

is reached and there is a need of recharge it is displayed by

LCD and information is passed to the microcontroller. The

controller is programmed in such a way that it sends the

information to consumer module which is nothing but a cell

phone .If consumer did not recharge within specified time

then a message is sent from GSM modem connected to PC

at electricity office to GSM modem connected to

microcontroller which automatically disconnects the power

supply to that particular consumer. When consumer

recharges his/her balance then again message is sent from

electricity board to controller that connection is re-

established. Hence the process is fully automatic.

Home section

User section

MOBILE PHONE

EB section

Above block diagrams gives clear view of methodology

in which the proposed system works. The working process

is clearly explained in above paragraph. The PC in EB

section is programmed with .NET and this PC contains all

the database of consumers.

E. MAX 232 (Communication Interface)

RS-232 was created for one purpose, to Interface between

Data Terminal Equipment (DTE) and Data Communications

International Conference on Computing and Control Engineering (ICCCE 2012), 12 & 13 April, 2012

ISBN 978-1-4675-2248-9 © 2012 Published by Coimbatore Institute of Information Technology

Equipment (DCE) employing serial binary data interchange.

So as stated the DTE is the terminal or computer and the

DCE is the modem or other communications device. RS 232

is the most widely used serial I/O interfacing standard. In

RS 232, a 1 is represented by -3 to -25 v. while a 0 bit is +3

to + 25 v, making -3 to +3 undefined. For this reason, to

connect any RS 232 to a microcontroller system we must

use voltage converters such as MAX 232 to convert the TTL

logic levels to the RS 232. voltage level, and vice versa.

This chip is used when interfacing micro controller with PC

to check the Baud rate and changes the voltage level

because micro controller is TTL compatible whereas PC is

CMOS compatible.

Operating circuit of MAX232

F. .Relay circuit

Introduction

Relay is an electrical switch that opens and closes under

the control of another electrical circuit. In the original form,

the switch is operated by an electromagnet to open or close

one or many sets of contacts. It was invented by Joseph

Henry in 1835. Because a relay is able to control an output

circuit of higher power than the input circuit, it can be

considered to be, in a broad sense, a form of an electrical

amplifier.

Working

When an electric current is passed through the coil, the

resulting magnetic field attracts the armature and the

consequent movement of the movable contact or contacts

either makes or breaks a connection with a fixed contact. If

the set of contacts was closed when the relay was de-

energized, then the movement opens the contacts and breaks

the connection, and vice versa if the contacts were open.

When the current to the coil is switched off, the armature is

returned by a force, approximately half as strong as the

magnetic force, to its relaxed position. Usually this force is

provided by a spring, but gravity is also used commonly in

industrial motor starters. Most relays are manufactured to

operate quickly. In a low voltage application, this is to

reduce noise. In a high voltage or high current application,

this is to reduce arcing.

If the coil is energized with DC, a diode is

frequently installed across the coil, to dissipate the energy

from the collapsing magnetic field at deactivation, which

would otherwise generate a voltage spike dangerous to

circuit components. Some automotive relays already include

that diode inside the relay case. Alternatively a contact

protection network, consisting of a capacitor and resistor in

series, may absorb the surge. If the coil is designed to be

energized with AC, a small copper ring can be crimped to

the end of the solenoid. This "shading ring" creates a small

out-of-phase current, which increases the minimum pull on

the armature during the AC cycle

By analogy with the functions of the original

electromagnetic device, a solid-state relay is made with a

thruster or other solid-state switching device. To achieve

electrical isolation an opt coupler can be used which is a

light-emitting diode (LED) coupled with a photo transistor.

III. SOFTWARE IMPLEMENTATION

The microcontroller IC AT89C52 is programmed using

Embedded C language. Steps for software implementation is

given below

1. Initially serial data rate is set to 9600

2. LCD and GSM modules are initialized

3. Accuracy of GSM modem is tested

4. SMS sent by the user is read

5. Validity of the number is checked

6. As soon as SMS is received an indication for reception

is given

7. SMS is received in cell phone indicating that we should

make recharge as available balance is very less.

8. Space is made available for new data that is to be

received by clearing the old data

Algorithm

Step1.Connect GSM module to electric meter

Step2.Intiate baud rate and set it to 9600.

Step3.LCD display and GSM module are initialized

Step4.User punches his/her number for connecting to

his/her energy meter

Step5.The number is then validated

Step6.Bill is displayed by LCD which is interfaced with

GSM modem

Step7.Delay of 200 seconds is set and result is displayed

for that time

Step8.Bill is sent to users cell phone and LCD displays

the received message

Step9.Buzzer attached in the device buzzes indicating that

message has been sent successfully

Step10.The user on receiving the message recharges

through his/her phone

Step11.Stop

International Conference on Computing and Control Engineering (ICCCE 2012), 12 & 13 April, 2012

ISBN 978-1-4675-2248-9 © 2012 Published by Coimbatore Institute of Information Technology

IV. HARDWARE MODULE

V. CONCLUSION AND FUTURE HOPES

Proposed system is highly effective in penalising man

work and making the system fully automatic. Hence the

probability of error is negligible. Using wireless

communication is very big boon which enables instant

billing. In future this system can be utilised throughout the

world as communication is done by GSM which is a

universal standard

REFERENCES [1] Tarek Khalifa, Kshirasagar Naik and Amiya Nayak ” Prototype

Development of Single Phase Prepaid kWh

[2] Meter” presented at 2011 International Conference on Electrical

Engineering and Informatics 17-19 July 2011, Bandung, Indonesia

[3] ury, J. Miller, W., “Smart Prepaid Energy Meter Implementation,”

Power Delivery, IEEE Transactions on, Jan 2002, pp. 1-5,

[4] “The 8051 microcontroller and embedded systems” by Muhammad

Ali Mazidi, Publisher: Prentice Hall.

[5] Alessandro Ferrero, Marco Faifer, and Simona Salicone “On Testing

the Electronic Revenue Energy Meters,”presented at IEEE

TRANSACTIONS ON INSTRUMENTATION AND

MEASUREMENT, VOL. 58, NO. 9, SEPTEMBER 2009

[6] Tarek Khalifa, Kshirasagar Naik and Amiya Nayak” A Survey of

Communication Protocols for Automatic Meter Reading Applications

,”at IEEE COMMUNICATIONS SURVEYS & TUTORIALS, VOL.

13, NO. 2, SECOND QUARTER 2011