energy meter thefting

AProject report

on

‘ENERGYMETER THEFT USING MICROCONTROLLER’

Submitted in the partial fulfillment for award the degree ofBachelor of Technology

from

Rajasthan Technical University, Kota, Rajasthan.

Submitted byHIMANSHU SHARMA , GARVE LUNKAD , DEOVRAT AND

KANISHK VIJAY MAHENDRA B.Tech. IVth Year.

Electrical Engineering

Guided byMiss. NEHA TIWARI

Assistant ProfessorDepartment of Electrical Engineering

Submitted toDepartment of Electrical Engineering

GYAN VIHAR SCHOOL OF ENGG. & TECH.Mahal Jagatpura, Jaipur. Rajasthan

Session 2010-11

1

CERTIFICATE

This is to certify that Mr. HIMANSHU SHARMA student of Final

Year B.Tech VIII semester Electrical Engineering of Gyan Vihar

School of Engineering and Technology , during the academic session

2010-11 has worked for his major project on “ ENERGYMETER

THEFT USING MICROCONTROLLER ” in the partial

fulfillment for award the degree of Bachelor of Technology in

Electrical Engineering from Rajasthan Technical University syllabus.

Work done by candidate is original and satisfactory.

Date: ……………..

Place: ……………..

Project Guide Project co-ordinator

Miss NEHA TIWARI Mr. AMIT SHRIVASTAVA Assistant Professor. Asso. Prof. & H.O.D. Department of Department of Electrical Engg.

Department of Electrical Engg.. GVSET, Jaipur GVSET, Jaipur

2

CERTIFICATE

This is to certify that Mr. DEOVRAT student of Final Year B.Tech

VIII semester Electrical Engineering of Gyan Vihar School of

Engineering and Technology , during the academic session 2010-11

has worked for his major project on “ ENERGYMETER THEFT

USING MICROCONTROLLER ” in the partial fulfillment for

award the degree of Bachelor of Technology in Electrical Engineering

from Rajasthan Technical University syllabus. Work done by

candidate is original and satisfactory.

Date: ……………..

Place: ……………..

.




3

CERTIFICATE

This is to certify that Mr. GARVE LUNKAD student of Final Year

B.Tech VIII semester Electrical Engineering of Gyan Vihar School of

Engineering and Technology , during the academic session 2010-11

has worked for his major project on “ ENERGYMETER THEFT

USING MICROCONTROLLER ” in the partial fulfillment for

award the degree of Bachelor of Technology in Electrical Engineering

from Rajasthan Technical University syllabus. Work done by

candidate is original and satisfactory.

Date: ……………..

Place: ……………..

.




4

CERTIFICATE

This is to certify that Mr. KANISHK VIJAY MAHENDRA student

of Final Year B.Tech VIII semester Electrical Engineering of Gyan

Vihar School of Engineering and Technology , during the academic

session 2010-11 has worked for his major project on “

ENERGYMETER THEFT USING MICROCONTROLLER ” in

the partial fulfillment for award the degree of Bachelor of Technology

in Electrical Engineering from Rajasthan Technical University

syllabus. Work done by candidate is original and satisfactory.

Date: ……………..

Place: ……………..

.




5

ACKNOWLEDGEM ENT

I take this opportunity to express my deep to express my deep gratitude, indebtness and regard to our esteemed guide, NEHA TIWARI ( Assistant Professor , Department of EE ) for providing me with an opportunity to present my major project on “ ENERGYMETER THEFT USING MICROCONTROLLER”.

I would also like to thank, our project coordinator Mr. Amit Shrivastava ( Asso. Prof. & H.O.D , Department of EE) for his valuable guidance and cooperation without which this project would have not been possible.

I would also like to express my heartfelt gratitude to all our faculty members of EE department and friends for their support.

.

DEOVRAT SINGH GARVE LUNKAD KANISHK VIJAY MAHENDRA HIMASHU SHARMA

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ABSTRACT

Science and technology with all its miraculous advancements has fascinated human life to a great extent that imagining a world without these innovations is hardly possible. While technology is on the raising slope, we should also note the increasing immoral activities. With a technical view, "Power Theft" is a non-ignorable crime that is highly prevalent, and at the same time it directly affects the economy of a nation. Data collected over Tirunelveli District, Bhel Trichy proves the necessity of this project.Detecting and eradicating such crimes with the assistance of the developing scientific field is the "Need of the Hour". With these views was this paper conceived and designed. Our paper provides a complete and comprehensive tool to prevent power theft which is very simple to understand and easy to implement(Accepted by T.N.E.B officials). It includes four sections - transmitting, receiving, counter display and processing sections. DESCRIPTION OF OUR IMPLEMENTATION IDEAS:The disc revolutions are sensed into pulses by optical slot sensor. These pulses are shaped and given as control signal to the CMOS switch which bypasses carrier wave generated by PLL provides as input to receiving section where transmitted signal is selected by the Intermediate frequency transformer. For each lock a pulse is sent out. The counter section is designed to send out pulse for every six input pulse from the receiver section. This count is parallely distributed in a 7-segmentdisplay and then to uc for further processing. uc performs the function of indication and identification. Pindetails, features, connections and software employed for uc89c51 are described in detail.We believe our implementation ideas is a boon to the electricity board offering them a chance to detect accurately the location and amount of power theft. Logical view for a digital meter is also included in our presentation

.

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PREFACE

With a technical view, "Power Theft" is a non-ignorable crime that is highly prevalent, and at the same time it directly affects the economy of a nation. While technology is on the raising

slope, we should also note the increasing immoral activities. . Our paper provides a complete and comprehensive tool to prevent power theft which is very simple to understand and easy to implement(Accepted by T.N.E.B officials).

The counter section is designed to send out pulse for every six input pulse from the receiver section. This count is parallely distributed in a 7-segmentdisplay and then to uc for further processing. uc performs the function of indication and identification

ORGANIZATION OF THESIS

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This project consists of mainly two sections. One section

consists of energy meter, isolator and receiver + comparator situated

on our supply pole and the one consists of energy meter isolator and

transmitter, situated in our homes.

The energy meter 1 & 2 can measure the energy by

measuring voltage and current. Voltage can measure directly with the

help of voltmeter provided on the energy meter but for measuring

current it requires a Current transformer (C.T.). The C.T. can measure

current by measuring magnetic field induced from a current carrying

thick copper wire using a coil. Energy meter consists of four LED’s to

show the status. One LED (transparent red LED) blinks with a

constant time interval. This time interval reduces with increase in

LOAD.

The energy meter at our home measures the energy

consumed by different LOADs. The output from energy meter (from

blinking LED) is given to transmitter section through isolator. Isolator

consists of a relay and a driver for switching it by energy meters

output. The isolator prevents the transmitter section from high voltage

output of energy meter. The isolator output is used to drive one out of

four inputs of the transmitter. This signal is decoded using encoder IC

HT12E and transmitted using RF transmitter module.

At the pole the energy meter 1 will measure the supplied

electric energy to the home by similar method, by measuring voltage

and current using C.T. The output of energy meter is fed to the trigger

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input of the receiver section through isolator. This isolator also

consists of a relay and a transistor driver circuit.

The receiver section consists of RF receiver to receive the

signal transmitted from the home transmitter section. It consists of

various LED’s to show the status. LED 5(orange LED) will blink to

show proper transmission from transmitter at home to the receiver at

pole. If this LED L5 does not blink, it indicates that there is a problem

in the RF link between Tx and Rx. LED 4 is by default ON. The

triggered input wills ON the LED L3. The next pulse received from

the transmitter section OFF LED L3.

Since the energy meter at pole measure the same energy as

measured by the home energy meter i.e. the energy delivered to the

LOAD (various appliances). The pulse rate of blinking LED’s of both

energy meters is same. In case of any theft i.e. bypassing the home

energy meter or taking energy before our home energy meter the

pulse rate of blinking LED of the home energy meter will reduce

while the pulse rate of blinking LED at the pole energy meter will

remain same. It will lead to continuous ON of LED L3. As LED L3

continuously glows for more than one minute it will switch OFF the

relay to cut the supply to the home. At this situation LED L4 turn

OFF and LED’s L2 and L3 will glow continuously to show the

occurrence of fault.

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CONTENTS

Chapter Title

1. Introduction

2. Basic Electrical Components

3. Power Supply

4. Relays

5. Printed Circuit Board

6. RF Module

7. Conclusion

INTRODUCTION

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"TODAY'S TECHNICIANS ARE SO FOCUSSED ON THE TREES OF TECHNOLOGICAL CHANGE THAT THEY FAIL TO SEE

THE FOREST; THE UNDERLYING ECONOMIC FORCES THAT DETERMINE SUCCESS AND FAILURE..."

"TECHNOLOGY CHANGES ECONOMY LAWS DO NOT"Electricity is the modern man's most convenient and useful form of energy without which the present social infrastructure would not be feasible. The increase in per capita production is the reflection of the

increase in the living standard of people. When importance of electricity is on the increasing side, then how much should theft of this energy or illegal consumption of power from the transmission lines be averted? Power theft has become a great challenge to the

electricity board. The dailies report that Electricity Board suffers a total loss of 8 % in revenue due to power theft every year, which has to controlled. Our paper identifies the Power theft and indicates it to the Electricity board through Power line. We had also dealt about the

remote monitoring of an energy meter. MICROCONTROLLER BASED

Basic Electronic Components

Resistors

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Resistors are components that have a predetermined resistance. Resistance determines how much current will flow through a component. Resistors are used to control voltages and currents. A very high resistance allows very little current to flow. Air has very high resistance. Current almost never flows through air. (Sparks and lightning are brief displays of current flow through air. The light is created as the current burns parts of the air.) A low resistance allows a large amount of current to flow. Metals have very low resistance. That is why wires are made of metal. They allow current to flow from one point to another point without any resistance. Wires are usually covered with rubber or plastic. This keeps the wires from coming in contact with other wires and creating short circuits. High voltage power lines are covered with thick layers of plastic to make them safe, but they become very dangerous when the line breaks and the wire is exposed and is no longer separated from other things by insulation.

Resistance is given in units of ohms. (Ohms are named after Mho Ohms who played with electricity as a young boy in Germany.) Common resistor values are from 100 ohms to 100,000 ohms. Each resistor is marked with colored stripes to indicate its resistance.

Variable Resistors

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Variable resistors are also common components. They have a dial or a knob that allows you to change the resistance. This is very useful for many situations. Volume controls are variable resistors. When you change the volume you are changing the resistance which changes the current. Making the resistance higher will let less current flow so the volume goes down. Making the resistance lower will let more current flow so the volume goes up. The value of a variable resistor is given as its highest resistance value. For example, a 500 ohm variable resistor can have a resistance of anywhere between 0 ohms and 500 ohms. A variable resistor may also be called a potentiometer (pot for short).

Capacitors

Now suppose you want to control how the current in your circuit changes (or not changes) over time. Now why would you? Well radio signals require very fast current changes. Robot motors cause current fluctuations in your circuit which you need to control. What do you do when batteries cannot supply current as fast as you circuit drains them? How do you prevent sudden current spikes that could fry your

robot circuitry? The solution to this is capacitors.

Capacitors are like electron storage banks. If your circuit is running low, it will deliver electrons to your circuit.

In our water analogy, think of this as a water tank with water always flowing in, but with drainage valves opening and closing. Since

capacitors take time to charge, and time to discharge, they can also be used for timing circuits. Timing circuits can be used to generate signals such as PWM or be used to turn on/off motors in solar

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powered BEAM robots. Quick note, some capacitors are polarized, meaning current can only

flow one direction through them. If a capacitor has a lead that is longer than the other, assume the longer lead must always connect

to positive.

Power surge /drainage management

The problem with using robot components that drain a large amount of power is sometimes your battery cannot handle the high drain rate, Motors and servos being perfect examples. This would cause a system wide voltage drop, often resetting your microcontroller, or at least causing it to not work properly. Just a side note, it is bad to use the same power source for both your circuit and your motors. So don't do it. Or suppose your robot motors are not operating at its full potential because the battery cannot supply enough current, the capacitor will make up for it. The solution is to place a large electrolytic capacitor between the source and ground of your power source. Get a capacitor that is rated at least twice the voltage you expect to go through it. Have it rated at 1mF-10mF for every amp required. For example, if your 20V motors will use 3 amps, use a 3mF-30mF 50V rated capacitor. Exactly how much will depend on how often you expect your motor to change speed and direction, as well as momentum of what you are actuating. Just note that if your capacitor is too large, it may take a long time to charge up when you first turn your robot on. If it is too small, it will drain of electrons and your circuit will be left with a deficit. It is also bad to allow a large capacitor to remain fully charged when you turn off your robot. Some things could accidentally short and fry. So use a simple power on LED in your motor circuit to drain the capacitor after your robot is turned off. If your capacitor is not rated properly for voltage, then can explode with smoke. Fortunately they do not overheat if given excessive amounts of current. So just make sure your capacitor is rated higher than your highest expected.

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Capacitors can also be used to prevent power spikes that could potentially fry circuitry. Next to any on/off switch or anything that that could affect power suddenly should have a capacitor across it?

Capacitors can eliminate switch bouncing. When you flip a mechanical switch, the switch actually bounces several times within a microsecond range. Normally this is too small of a time for anyone to care (or even notice), but note that a microcontroller can take hundreds of readings in a single microsecond. So if your robot was counting the number of times a switch is flipped, a single flip can count as dozens. So how do you stop this? Use a small ceramic capacitor! Just experiment until you find the power capacitance value.

Diodes

Diodes are components that allow current to flow in only one direction. They have a positive side (leg) and a negative side. When the voltage on the positive leg is higher than on the negative leg then current flows through the diode (the resistance is very low). When the voltage is lower on the positive leg than on the negative leg then the current does not flow (the resistance is very high). The negative leg of a diode is the one with the line closest to it. It is called the cathode. The positive end is called the anode.

Usually when current is flowing through a diode, the voltage on the positive leg is 0.65 volts higher than on the negative leg.

Switches

Switches are devices that create a short circuit or an open circuit depending on the position of the switch. For a light switch, ON means short circuit (current flows through the switch, and lights light up.) When the switch is OFF, that means there is an open circuit (no current flows, lights go out.

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When the switch is ON it looks and acts like a wire. When the switch is OFF there is no connection.

The LED

An LED is the device shown above. Besides red, they can also be yellow, green and blue. The letters LED stand for Light Emitting Diode. The important thing to remember about diodes (including LEDs) is that current can only flow in one direction.

The Transistor

Transistors are basic components in all of today's electronics. They are just simple switches that we can use to turn things on and off. Even though they are simple, they are the most important electrical component. For example, transistors are almost the only components used to build a Pentium processor. A single Pentium chip has about 3.5 million transistors. The ones in the Pentium are smaller than the ones we will use but they work the same way.

Transistors that we will use in projects look like this:

The transistor has three legs, the Collector (C), Base (B), and Emitter (E). Sometimes they are labeled on the flat side of the transistor. Transistors always have one round side and one flat side. If the round side is facing you, the Collector leg is on the left, the Base leg is in the middle, and the Emitter leg is on the right.

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Transistor Symbol

The following symbol is used in circuit drawings (schematics) to represent a transistor.

Basic Circuit

The Base (B) is the On/Off switch for the transistor. If a current is flowing to the Base, there will be a path from the Collector (C) to the Emitter (E) where current can flow (The Switch is On.) If there is no current flowing to the Base, then no current can flow from the Collector to the Emitter. (The Switch is off.)

Below is the basic circuit we will use for all of our transistors.

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POWER SUPPLY

Power supply can be defined as electronic equipment, which is a stable source of D.C. power for electronic circuits.

Power supply can be classified into two major categories: -

Unregulated power supply Regulated power supply

UNREGULATED POWER SUPPLY: -

These power supplies, supply power to the load but do not take into variation of power supply output voltage or current with respect to the change in A.C. mains voltage, load current or temperature variations. In other words, we can say that the output voltage or current of an unregulated power supply changes with the change in A.C.mains voltage, load current and temperature.

A block diagram as shown below can represent unregulated power supply:

A .C. INPUTRECTIFIER FILTERLOAD

BLOCK DIAGRAM OF UNREGULATED POWER SUPPLY

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REGULATED POWER SUPPLY: -

These power supplies are regulated over the change in source voltage or load current i.e. its output remain stable.

Regulated power supplies are of two types: -

CURRENT REGULATED POWER SUPPLIES These are constant current supplies in spite of change in load or input voltage.

VOLTAGE REGULATED POWER SUPPLIES These supplies supply constant output voltage

with respect to the variation in load or source input voltage.

Block diagram of a regulated power supply can be given as below:

RECTIFIER FILTERREGULATORLOADA.C.

INPUTVac Vdc VL

UNREGULATED POWER SUPPLY

BLOCK DIAGRAM OF REGULATED POWER SUPPLY

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CIRCUIT OF REGULATED POWER SUPPLY WITH HALF WAVE RECTIFIER AND IC-7809 AS A REGULATOR

C20.1uF

IN

COM

OUT

C11000uF

D4D3D2D1

T110TO1 OUTPUT

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Here diode D1, D2, D3 and D4 forms half wave rectifier. Capacitor C1 is filtering capacitor. IC-7809 is used for voltage regulation. Capacitor C2 is used for bypassing, if any ripples are present then it eliminates those ripples.

As IC-7809 is used so it gives 9v dc regulated voltage ideally. If we take 16 volts transformer then we will get 8.97v at output. Thus voltage is regulated.

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Relays

A relay is usually an electromechanical device that is actuated by an electrical current. The current flowing in one circuit causes the opening or closing of another circuit. Relays are like remote control switches and are used in many applications because of their relative simplicity, long life, and proven high reliability. They are used in a wide variety of applications throughout industry, such as in telephone exchanges, digital computers and automation systems.

How do relays work?

All relays contain a sensing unit, the electric coil, which is powered by AC or DC current. When the applied current or voltage exceeds a threshold value, the coil activates the armature, which operates either to close the open contacts or to open the closed contacts. When a power is supplied to the coil, it generates a magnetic force that actuates the switch mechanism. The magnetic force is, in effect, relaying the action from one circuit to another. The first circuit is called the control circuit; the second is called the load circuit. A relay is usually an electromechanical device that is actuated by an electrical current.

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The current flowing in one circuit causes the opening or closing

of another circuit.

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Types of Relays

There are two basic classifications of relays:

1. Electromechanical Relay 2. Solid State Relay.

Electromechanical relays have moving parts, whereas solid state relays have no moving parts. Advantages of Electromechanical relays include lower cost, no heat sink is required, multiple poles are available, and they can switch AC or DC with equal ease.

1. Electromechanical Relays

General Purpose Relay: The general-purpose relay is rated by the amount of current its switch contacts can handle. Most versions of the general-purpose relay have one to eight poles and can be single or double throw. These are found in computers, copy machines, and other consumer electronic equipment and appliances.

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Power Relay: The power relay is capable of handling larger power loads – 10-50 amperes or more.

They are usually single-pole or double-pole units.

Contactor: A special type of high power relay, it’s used mainly to control high voltages and currents in industrial electrical applications. Because of these high power requirements, contactors always have double-make contacts.

Time-Delay Relay: The contacts might not open or close until some time interval after the coil has been energized. This is called delay-on-operate. Delay-on-release means that the contacts will remain in their actuated position until some interval after the power has been removed from the coil.

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A third delay is called interval timing. Contacts revert to their alternate position at a specific interval of time after the coil has been energized.

The timing of these actions may be a fixed parameter of the relay, or adjusted by a knob on the relay itself, or remotely adjusted through an external circuit.

2. Solid State Relays

These active semiconductor devices use light instead of magnetism to actuate a switch. The light comes from an LED, or light emitting diode. When control power is applied to the device’s output, the light is turned on and shines across an open space.

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On the load side of this space, a part of the device senses the presence of the light, and triggers a solid state switch that either opens or closes the circuit under control.

Often, solid state relays are used where the circuit under control must be protected from the introduction of electrical noises.

Advantages of Solid State Relays include low EMI/RFI, long life, no moving parts, no contact bounce, and fast response.

The drawback to using a solid state relay is that it can only accomplish single pole switching.

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Printed circuit boards

The use of miniaturization and sub miniaturization in electronic equipment

design has been responsible for the introduction of a new technique in inters

component wiring and assembly that is popularly known as printed circuit.

The printed circuit boards (PCBs) consist of an insulating substrate material

with metallic circuitry photo chemically formed upon that substrate. Thus PCB

provides sufficient mechanical support and necessary electrical connections for

an electronic circuit.

Advantages of printed circuit boards: -

1) Circuit characteristics can be maintained without introducing

variations inter circuit capacitance.

2) Wave soldering or vapour phase reflow soldering can mechanize

component wiring and assembly.

3) Mass production can be achieved at lower cost.

4) The size of component assembly can be reduced with

corresponding decrease in weight.

5) Inspection time is reduced as probability of error is eliminated.

Types of PCB’s: -

There are four major types of PCB’s: -

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1) Single sided PCB: - In this, copper tracks are on one side of the board,

and are the simplest form of PCB. These are simplest to manufacture thus

have low production cost.

2) Double sided PCB:- In this, copper tracks are provided on both sides of

the substrate. To achieve the connections between the boards, hole

plating is done, which increase the manufacturing complexity.

3) Multilayered PCB: - In this, two or more pieces of dielectric substrate

material with circuitry formed upon them are stacked up and bonded

together. Electrically connections are established from one side to the

other and to the layer circuitry by drilled holes, which are subsequently

plated through copper.

4) Flexible PCB: - Flexible circuit is basically a highly flexible variant of

the conventional rigid printed circuit board theme.

PCB Manufacturing Process: -

There are a number of different processes, which are used to manufacture a

PCB, which is ready for component assembly, from a copper clad base

material. These processes are as follows

Preprocessing: - This consists of initial preparation of a copper clad

laminate ready for subsequent processing. Next is to drill tooling holes.

Passing a board through rollers performs cleaning operation.

Photolithography: - This process for PCBs involves the exposure of a

photo resist material to light through a mask. This is used for defining

copper track and land patterns.

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Etching: - The etching process is performed by exposing the surface of

the board to an etchant solution which dissolves away the exposed copper

areas .The different solutions used are: FeCl, CuCl, etc.

Drilling: - Drilling is used to create the component lead holes and

through holes in a PCB .The drilling can be done before or after the track

areas have been defined.

Solder Masking: - It is the process of applying organic coatings

selectively to those areas where no solder wettings is needed .The solder

mask is applied by screen-printing.

Metal Plating: - The plating is done to ensure protection of the copper

tracks and establish connection between different layers of multiplayer

boards. PCBs are stacked before being taken for final assembly of

components .The PCB should retain its solder ability.

Bare-Board Testing: - Each board needs to ensure that the required

connections exist, that there are no short circuits and holes are properly

placed .The testing usually consists of visual inspection and continuity

testing

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RF TRANSMITTER AND RECEIVER MODULE:

These modules are now widely and cheaply available with the operating frequency of 433 MHz. The transmitter module accepts serial data. The encoder IC takes in parallel data at the TX side packages it into serial format and then transmits it with the help of a RF transmitter module. At the RX end, the decoder IC receives the signal via the RF receiver module, decodes the serial data and reproduces the original data in the parallel format.

FEATURES

Range in open space (Standard Conditions): 100 Meters RX Receiver Frequency: 433 MHz Low Power Consumption Easy For Application RX Operating Voltage: 5V TX Frequency Range: 433.92 MHzTX Supply Voltage: 3V ~ 6V

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Fig 1.1.2.4.1 433 MHz Transmitter

Fig 1.1.2.4.2 433 MHz RF Receiver

1.1.2.5THE TX433 (Transmission Module):

The TX433 wireless RF transmitter uses on/off keying to transmit data to the matching receiver, RX433. The data input “keys” the saw resonator in the transmitter when the input is +3 volts or greater, AM modulating the data onto the 433 MHz carrier. The data is then demodulated by the receiver, which accurately reproduces the original data. The data input is CMOS level Compatible when the unit is run on +5 volts.

When driving with a CMOS input, there must be enough level to achieve at least 3V on the data input, 5V is preferable. This is due to the start-up time of the oscillator needing to be fast to accurately reproduce your data. If the

33

voltage is too low, the oscillator will not start fast enough to accurately reproduces your data, especially at higher data rates. Luckily not much drive is needed, so this should be easy since it is 22K ohms of load. Almost any CMOS output will drive this without any problems. There are some CMOS outputs which have very little drive capability which may not work, so testing the voltage at the data input may be a wise choice if you are having problems.

1.1.2.6 The RX433 (Receiver Module):

The receiver shown in Figure also contains just one transistor. It is biased to act as a regenerative oscillator, in which the received antenna signal causes the transistor to switch to high amplification, thereby automatically arranging the signal detection. Next, the ‘raw’ demodulated signal is amplified and shaped-up by op-amps. The result is a fairly clean digital signal at the output of the receiver. The logic high level is at about 2/3 of the supply voltage, i.e., between 3 V and 4.5 V.

The range of the simple system shown in Figures is much smaller than that of more expensive units, mainly because of the low transmit power (approx. 1 mW) and the relative insensitivity and wide-band nature of the receiver. Moreover, amplitude-modulated noise is not suppressed in any way.

1.1.2.7 ANTENNA CONSIDERATIONS:

The simplest antenna consists of a piece of wire approximately 6 to 7 inches long. If you desire more range you can try a ground plane antenna or a Yagi such as the Ramsey 400-4 model. The antenna should be tuned for the 433 MHz band for best operation.

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Having two Yagi antennas, one for the transmitter and one for the receiver will allow you to extend the range considerably, but since they are directional, this would be best for if your receiver and transmitter are in fixed positions.

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CIRCUIT DIAGRAM & WORKING:-

Functional Block Diagram of Energy Theft Detector

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This project consists of mainly two sections. One section consists of energy

meter, isolator and receiver + comparator situated on our supply pole and the

one consists of energy meter isolator and transmitter, situated in our homes.

The energy meter 1 & 2 can measure the energy by measuring

voltage and current. Voltage can measure directly with the help of voltmeter

provided on the energy meter but for measuring current it requires a Current

transformer (C.T.). The C.T. can measure current by measuring magnetic field

induced from a current carrying thick copper wire using a coil. Energy meter

consists of four LED’s to show the status. One LED (transparent red LED)

blinks with a constant time interval. This time interval reduces with increase in

LOAD.

The energy meter at our home measures the energy consumed by

different LOADs. The output from energy meter (from blinking LED) is given

to transmitter section through isolator. Isolator consists of a relay and a driver

for switching it by energy meters output. The isolator prevents the transmitter

section from high voltage output of energy meter. The isolator output is used to

drive one out of four inputs of the transmitter. This signal is decoded using

encoder IC HT12E and transmitted using RF transmitter module.

At the pole the energy meter 1 will measure the supplied electric

energy to the home by similar method, by measuring voltage and current using

C.T. The output of energy meter is fed to the trigger input of the receiver

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section through isolator. This isolator also consists of a relay and a transistor

driver circuit.

The receiver section consists of RF receiver to receive the signal

transmitted from the home transmitter section. It consists of various LED’s to

show the status. LED 5(orange LED) will blink to show proper transmission

from transmitter at home to the receiver at pole. If this LED L5 does not blink,

it indicates that there is a problem in the RF link between Tx and Rx. LED 4 is

by default ON. The triggered input wills ON the LED L3. The next pulse

received from the transmitter section OFF LED L3.

Since the energy meter at pole measure the same energy as measured

by the home energy meter i.e. the energy delivered to the LOAD (various

appliances). The pulse rate of blinking LED’s of both energy meters is same.

In case of any theft i.e. bypassing the home energy meter or taking energy

before our home energy meter the pulse rate of blinking LED of the home

energy meter will reduce while the pulse rate of blinking LED at the pole

energy meter will remain same. It will lead to continuous ON of LED L3. As

LED L3 continuously glows for more than one minute it will switch OFF the

relay to cut the supply to the home. At this situation LED L4 turn OFF and

LED’s L2 and L3 will glow continuously to show the occurrence of fault.

Internal description of the RF Transmitter and Receiver is:-

1) RF Transmitter:-

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The RF Tx consists of RF Tx module, an encoder i.e. HT12E, four

switches and the transmitting antenna. The energy meter 2 is connected to RF

Tx with the help of Isolator. Isolators are nothing but relay circuit consists of a

resistor, transistor and an inductor connected to 12V supply and of course

relay. RF Tx has four switches viz. S1, S2, S3 and S4. Isolator relay is

connected to S4 switch of the RF Tx. The main function of RF Tx is to change

the state of LED L4. If the LED is ON it will turn it OFF and if it is OFF it

will turn it ON. All the switches is then connected to the encoder HT12E

whose output drives the RF Tx module unit and then it is transmitted with the

help of an antenna. The transmitter module accepts serial data. The encoder IC

takes in parallel data at the TX side packages it into serial format and then

transmits it with the help of a RF transmitter module. At the RX end, the

decoder IC receives the signal via the RF receiver module, decodes the serial

data and reproduces the original data in the parallel format.

Encoder HT 12E

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The 212 encoders are a series of CMOS LSI’s for remote control system

applications. They are capable of encoding information which consists of N

address bits and 12_N data bits. Each address/data input can be set to one of

the two logic states. The programmed addresses/data are transmitted together

with the header bits via an RF or an infrared transmission medium upon receipt

of a trigger signal. The capability to select a TE trigger on the HT12E or a

DATA trigger on the HT12A further enhances the application flexibility of the

212 series of encoders. The HT12A additionally provides a 38 kHz carrier for

infrared systems.

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Note: D8~D11 are all data input and transmission enable pins of the HT12A.

TE is a transmission enable pin of the HT12E.

The 2^12 series of encoders begin a 4-word transmission cycle upon receipt of

a transmission enable (TE for the HT12E or D8~D11 for the HT12A, active

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low). This cycle will repeat itself as long as the transmission enable (TE or

D8~D11) is held low. Once the transmission enables returns high the encoder

output completes its final cycle and then stops as shown below.

The TX433 wireless RF transmitter uses on/off keying to transmit data

to the matching receiver, RX433. The data input “keys” the saw resonator in

the transmitter when the input is +3 volts or greater, AM modulating the data

onto the 433 MHz carrier. The data is then demodulated by the receiver, which

accurately reproduces the original data. The data input is CMOS level

Compatible when the unit is run on +5 volts.

When driving with a CMOS input, there must be enough level to

achieve at least 3V on the data input, 5V is preferable. This is due to the start-

up time of the oscillator needing to be fast to accurately reproduce your data. If

the voltage is too low, the oscillator will not start fast enough to accurately

reproduce your data, especially at higher data rates. Luckily not much drive is

needed, so this should be easy since it is 22K ohms of load. Almost any CMOS

output will drive this without any problems. There are some CMOS outputs

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which have very little drive capability which may not work, so testing the

voltage at the data input may be a wise choice if you are having problems.

Fig. 433 MHz Transmitter

2) RF Receiver:-

This section consists of five LED’s (four yellow and one orange), RF

Rx module, decoder HT 12D, and PIC microcontroller 16F73 and a receiving

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antenna. Antenna receives the transmitted signal and that received signal is

then fed to the RF Rx module whose output is then provided to the decoder

HT12D and then to the PIC 16F73.

The receiver shown in Figure also contains just one transistor. It is

biased to act as a regenerative oscillator, in which the received antenna signal

causes the transistor to switch to high amplification, thereby automatically

arranging the signal detection. Next, the ‘raw’ demodulated signal is amplified

and shaped-up by op-amps. The result is a fairly clean digital signal at the

output of the receiver. The logic high level is at about 2/3 of the supply

voltage, i.e., between 3 V and 4.5 V. The range of the simple system shown in

Figures is much smaller than that of more expensive units, mainly because of

the low transmit power (approx. 1 mW) and the relative insensitivity and wide-

band nature of the receiver. Moreover, amplitude-modulated noise is not

suppressed in any way.

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Fig 433 MHz RF Receiver

The 2^12decoders are a series of CMOS LSI’s for remote control system

applications. They are paired with Holtek’s 2^12series of encoders (refer to the

encoder/decoder cross reference table).For proper operation, a pair of

encoder/decoder with the same number of addresses and data format should be

chosen. The decoders receive serial addresses and data from a programmed

2^12 series of encoders that are transmitted by a carrier using an RF or an IR

transmission medium. They compare the serial input data three times

continuously with their local addresses. If no error or unmatched

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codes are found, the input data codes are decoded and then transferred to the

output pins. The VT pin also goes high to indicate a valid transmission. The

2^12 series of decoders are capable of decoding in formations that consist of N

bits of address and 12_N bits of data. Of this series, the HT12D is arranged to

provide 8 address bits and 4 data bits, and HT12F is used to decode 12 bits of

address information.

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The 2^12 series of decoders provides various combinations of addresses and

data pins in different packages so as to pair with the 2^ 12 series of encoders.

The decoders receive data that are transmitted by an encoder and interpret the

first N bits of code period as addresses and the last 12_N bits as data, where N

is the address code number. A signal on the DIN pin activates the oscillator

which in turn decodes the incoming address and data. The decoders will then

check the received address three times continuously. If the received address

codes all match the contents of the decoder’s local address, the 12_N bits of

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data are decoded to activate the output pins and the VT pin is set high to

indicate a valid transmission. This will last unless the address code is incorrect

or no signal is received. The output of the VT pin is high only when the

transmission is valid. Otherwise it is always low. Of the 2^12 series of

decoders, the HT12F has no data output pin but its VT pin can be used as a

momentary data output. The HT12D, on the other hand, provides 4 latch type

data pins whose data remain unchanged until new data are received.

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FIGURE: PIC16F73 BLOCK DIAGRAM

The main function of PIC16F73 is to trip the relay circuit when ever the LED L3 remains ON or OFF for one minute. By tripping the relay we are cutting off the connection of the energy meter 2.

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Conclusion

This paper defines electricity theft in social, economical, regional, political, literacy, criminal, and corruption points of view. This paper illustrates various cases, issues and setbacks in the design, development, deployment, operation, and maintenance of electricity theft controlling devices. In addition, various factors that influence people to steal electricity are discussed. This paper illustrates the effect of NTL on quality of supply, burden on the generating station and tariff imposed on genuine customer. In addition, we proposed a system to detect and reduce the electricity theft by chastising the appliances of people responsible for theft. Architectural models of smart meter, communication system, harmonic generator, and hybrid filter are proposed. Operational principle of the proposed system is illustrated in detail. For illustration, cost–benefit analysis for implementation and maintenance of the proposed system in India is presented.

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energy meter thefting

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