energy meter thefting
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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: ……………..
.
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
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: ……………..
.
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
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: ……………..
.
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
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
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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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