Project Report

On

STUDY AND IMPLEMENTATION OF WIRELESS ENERGY METER

Submitted to

R.T.M. Nagpur University in partial

fulfillment of the requirements

for the award of

Degree of Bachelor of Engineering

in

Electrical Engineering

Submitted by

Chetan S. Kadu Sachin C. Suke

Mangesh M. Ukey

Under the Guidance of

J. G. Chaudhari

Department of Electrical Engineering

G.H. Raisoni College of Engineering, Nagpur

2007-2008

ACKNOWLEDGEMENT

Success is the manifestation of

perseverance, inspiration and motivation. We,

the projectees, ascribe our success in this

venture to J.G. Chaudhari, project guide. His

endeavor for perfection, indefatigable zeal and

enthusiasm, foresight and innovation

contributed in a big way in the successful

completion of this project within the estimated

time. This work is a reflection of his ideas and

concept and above all his sincere interest.

We are deeply indebted to Dr P.R.Bajaj,

Principal and Dr. V.K. Chandrakar, Head of

Department for their keen interest and

valuable suggestion from time to time lead to

make this project near perfection.

Last but not the least we thank all

supporting staff of the department and our

friends whose timely ideas and inspiration lead

to successful completion of our project

………..Projectees

INDEX

CHAPTER

NO.

TITLE PAGE

NO.

1 INTRODUCTION 1

2 BLOCK DIAGRAM 4

3 MAIN COMPONENT 6

3.1 Electronic Energy Meter 7

3.2 Digital Pulse Generator 11

3.3 Microcontroller (IC 89C2051) 13

3.4 RF Transmitter 18

3.5 Implemented Model For RF

Transmitter

21

3.6 RF Receiver 22

3.7 Implemented Model For RF Receiver 25

4 WIRELESS ENERGY CONTROL UNIT 26

5 RADIO FREQUENCY IDENTIFICATION 29

6 POWER SUPPLY REQUIRMENTS 35

7 OTHER COMPONENTS 40

7.1 ATMEL 553 (AT 24C08A) 41

7.2 Voltage Regulator 43

7.3 Crystal Oscillator 44

7.4 Transistor 46

7.5 Resistor 49

7.6 Capacitor 50

7.7 Zener Diode 52

8 ADVANTAGES 54

9 LIMITATIONS 55

10 APPLICATIONS 56

11 CONCLUSION 57

12 FUTURE SCOPE 58

13 REFRENCES 59

14 APPENDIX 61

CHAPTER - 1

INTRODUCTION

Power sector players have made many efforts and spent considerable

money and resources in formulating strategies for improving collection

efficiency, however, these have seldom yielded encouraging results.

Metering is one of the major technical issues impacting the collection

efficiency of power companies. Currently, only a few percent of power

meters installed in India are electronic and rest are electromechanical.

Usually, the meter reading is taken once a month by the field

executives of the distribution company. The human errors involved in

collection of bills and old electronic & electromechanical type of meters

together have resulted in poor metering efficiency, zero metering, faulty

reading, bribing utilities executive to charge less units and tampering of the

meters to clock them reverse.

The demand for electrical energy is ever increasing. Today over 21%

(theft apart!!) of the total electrical energy generated in India is lost in

transmission (4-6%) and distribution (15-18%). The electrical power deficit

in the country is currently about 18%. Clearly, reduction in distribution

losses can reduce this deficit significantly. It is possible to bring down the

distribution losses to a 6-8 % level in India with the help of newer

technological options (including information technology) in the electrical

power distribution sector which will enable better monitoring and control.

…1…

The introduction of electronic energy meter for electrical energy

metering has resulted in various improvements in the operation of utilities

apart from the increase revenue due to better recording of energy

consumption. One such additional benefit is possibility of reading the meter

automatically using meter-reading instruments even without going near the

meter. The main purpose of project work is to design and developed a

tamper proof wireless energy meter, which can implement at big industries

and huge commercial complexes.

Electrical utilities face particular challenges in meeting continuously

changing customer load demands. At least two related reasons exist for these

challenges. First, power demands can fluctuate substantially from day to day

or hour to hour, making it difficult for utilities to ensure that they have

enough capacity to meet demand. These fluctuations in energy demand may

arise from ordinary cyclic energy usage patterns (for example peaking in the

afternoon), or else can result from an unexpected change in the balance

between energy supply and demand, such as where, for example, a power

generator linked to the power grid unexpectedly goes down, large energy

users go on or off line, or a fault occurs somewhere in the distribution

system. A second factor contributing to the challenges faced by power

utilities is the fact that power consumption in local areas tends to grow over

time, gradually placing increasing burdens on electrical utilities to meet the

growing demand. Because the construction of new power plants is very

costly and must comply with a variety of governmental regulations, it is

possible for a local or even large geographic region to find itself without the

power capacity to supply its current or anticipated future demand.

…2…

A major challenge for utility companies is handling peak energy

demands. This is because the energy supplied by power utilities must be

sufficient to meet the energy demand moment by moment, and peak

demands place the greatest strain on the power distribution system. When

energy demand outstrips available supply, disruptive events such as power

blackouts, brownouts or interruptions can occur. Not only can such events

cause substantial inconvenience to large numbers of people and businesses,

but they can also be dangerous or life-threatening—where, for example, the

power supply for hospitals or critical home care medical equipment is

compromised.

Historically, when power utilities serving a locality have been faced

with a severe energy situation caused by high demand, their options have

been extremely limited. Power utilities can, for example, request that

consumers conserve energy, but not all consumers follow such requests and,

in any event, conservation has not tended to provide a complete solution for

energy supply problems. Power utilities can attempt to satisfy peak demands

by purchasing available energy from a third party source connected to the

power grid, but such purchases, particularly at peak demand times, can be

extremely costly as energy suppliers often demand a premium when demand

is high.

…3…

CHAPTER - 2

BLOCK DIAGRAM

…4…

2.1 Working:

The supply is given to the input side of analog energy meter and

output connected to the load side. Analog meter is interface with

microcontroller (IC 89C2051). When load is on energy meter consumes

certain amount of energy. The number of unit consumed by the load is

shown by LED and with the help of digital pulse generator this analog signal

from led is fed to the microcontroller. Then this LED signal fed to

transmitter via ATMEL 553 timer IC in the for of digital signal (0, 1).

Crystal oscillator is used to generate the high value of frequency for IC

operation, due to higher value of frequency (24 MHZ) the digital signal fed

to transmitter circuit and transmitter circuit sends this signal via antenna to

the receiver circuit. At receiver circuit the signal is received and fed to the

signal generator with the help of carrier frequencies with suitable value.

After receiving the signal, amplifier amplifies that signal and

converting in to digital form, fed to microcontroller. LED display is directly

connected through microcontroller, it shows the display of unit consumes at

consumer side. This process takes place by electromagnetic wave by the

method of close proximity of electromagnetic propagation of

electromagnetic wave.

If consumer may try to tamper the meter by shorting the relay

contacts, the receiver receives more pulse than the credit, immediately alarm

energizes at receiver side and supply get trip from substation to consumed.

Hence it protects the circuit and protects the energy from theft.

…5…

CHAPTER - 3

MAIN COMPONENTS

Electronic Energy Meter

Digital Pulse Generator

Microcontroller (IC 89C2051)

RF Transmitter

RF Receiver

…6…

3.1 ELECTRONIC ENERGYMETER:

3.1.1 INTRODUCTION:

Power Measurement today introduced the next step in affordable

energy management. The wireless energy meter with a low installed cost,

exceptional scalability, and accuracy verified to national sub-billing

standards.

…7…

The meter offers an affordable energy monitoring solution for large

commercial properties, including office buildings and retail malls. This is

the addition to the Power Measurement line of wireless metering products.

The meters form a wireless network that automatically reports energy

consumption on each tenant space for individual and aggregate billing

purposes. Property managers can then use this information to help manage

accounts, conserve energy, and recover energy costs.

With no conduit or wires to run, installation is simple and

inexpensive. Each tenant is equipped with a wireless energy meter to record

usage, and an Wireless Gateway is installed nearby to receive radio signals

(from up to 100 meters). The gateway then converts the energy data into

industry or an enterprise energy management software program such as

Power Measurement's. Building managers can monitor energy usage as

real-time or logged data for anywhere in the network. To extend the reach of

wireless meters across longer distances, an optional ION Wireless Repeater

unit is also available in AC or solar-powered configurations.

An electronic energy meter refers to a type of advanced meter that

identifies consumption in more detail than a conventional meter and

optionally communicates that information via some network that to the local

utility for the monitoring and billing purpose.

ENERGY- drives the world- the masculine, the feminine and the

neuter all in all. Though energy can be of different forms like electrical.

Which are interring convertible using the technologies in hand.

…8…

METER – measure the amount of something exhausted and here it

measure the amount of energy consume. for using electricity need to pay the

electricity department.

Electronic energy meter is equipped with the wireless module. After

desired time the no. of unit will be transmitted to main super computer data

base. Thus, no need of personal visiting the place and noting down the

reading which will pass on to operator. Not only is this but the concept of

energy theft detection and thus it controlling the main source of inspiration

for us to work on this.

Electronic energy meter to measure electricity usage have so many

advantages over their electromechanically counter parts. Including accuracy,

flexibility and tampering detection that their adoption is spreading rapidly.

With this networking capability the meter can be installed numerous

of point in power distribution network not just at consumer premises to

monitor and optimized functioning the entire system.

The electronic energy meter has a power full capability to detect

tampering. The meter is ideally suitable for energy metering in the domestic

application and for auditing and a load management in industrial application.

…9…

3.1.2 ADVANTAGES:

Electronic energy meter are quite compact as compared to analog

meter.

Electronic energy meter require very less power consumption as

compared to analog device.

Electronic meter are less affected by environmental change in

conditions and magnetic field as against analog meter.

Electronic meter give quite good dynamic response much better than

electro mechanical type instrument for fluctuating loading condition.

Electronic meter have less aging problem, as these are static device and do not contain any rotary part.

…10…

3.2 DIGITAL PULSE GENERATOR:

Simple pulse generators usually allow control of the pulse repetition

rate (frequency), pulse width, delay with respect to an internal or external

trigger and the high- and low-voltage levels of the pulses. More-

sophisticated pulse generators may allow control over the rise time and fall

time of the pulses. Pulse generators may use digital techniques, analog

techniques, or a combination of both techniques to form the output pulses.

For example, the pulse repetition rate and duration may be digitally

controlled but the pulse amplitude and rise and fall times may be determined

by analog circuitry in the output stage of the pulse generator. With correct

adjustment, pulse generators can also produce a 50% duty cycle square

wave. Pulse generators are generally single-channel providing one

frequency, delay, width and output. Pulse generators are available for

generating output pulses having widths ranging from minutes down to under

1 picoseconds. In general, generators for pulses with widths over a few

microseconds employ digital counters for timing these pulses, while widths

between approximately 1 nanosecond and several microseconds are typically

generated by analog techniques such as RC (resistor-capacitor) networks or

switched delay lines. Pulse generators capable of generating pulses with

widths under approximately 100 picoseconds are often termed "microwave

pulsers", and typically generate these ultra-short pulses using Step recovery

diode (SRD) or Nonlinear Transmission Line (NLTL) methods. Step

Recovery Diode pulse generators are inexpensive but typically require

several volts.

…11…

NLTL-based pulse generators generally have lower jitter, but are more

complex to manufacture, and are not suited for integration in low-cost

monolithic ICs. A new class of microwave pulse generation architecture, the

RACE (Rapid Automatic Cascade Exchange) pulse generation circuit, is

implemented using low-cost monolithic IC technology and can produce

pulses as short as 1picoseconds, and with a repetition rates exceeding 30

billion pulses per second. These pulsars are typically used in military

communications applications, and low-power microwave transceiver ICs.

Pulse generators are generally voltage sources, with true current pulse

generators being available only from a few suppliers.

These pulses can then be injected into a device under test and used as

a stimulus or clock signal or analyzed as they progress through the device,

confirming the proper operation of the device or pinpointing a fault in the

device. Pulse generators are also used to drive devices such as switches,

lasers and optical components, modulators, intensifiers as well as resistive

loads. The output of a pulse generator may also be used as the modulation

signal for a signal generator.

…12…

3.3 MICROCONTROLLER (IC 89C2051):

(Pin Diagram for Microcontroller)

3.3.1 DESCRIPTION:

The AT89C2051 is a low-voltage, high-performance CMOS 8-bit

microcomputer with 2K bytes of Flash programmable and erasable read-only

memory (PEROM). The device is manufactured using Atmel’s high-density

nonvolatile memory technology and is compatible with the industry-standard

MCS-51 instruction set.

….13…

By combining a versatile 8-bit CPU with Flash on a monolithic chip,

the Atmel AT89C2051 is a powerful microcomputer which provides a

highly-flexible and cost-effective solution to many embedded control

applications.

The AT89C2051 provides the following standard features: 2K bytes of

Flash, 128 bytes of RAM, 15 I/O lines, two 16-bit timer/counters, a five

vector two-level interrupt architecture, a full duplex serial port, a precision

analog comparator, on-chip oscillator and clock circuitry. In addition, the

AT89C2051 is designed with static logic for operation down to zero

frequency and supports two software selectable power saving modes. The

Idle Mode stops the CPU while allowing the RAM, timer/counters, serial

port and interrupt system to continue functioning. The power-down mode

saves the RAM contents but freezes the oscillator disabling all other chip

functions until the next hardware reset. A microcontroller is a integrated

circuit with a following key features.

Central processing unit- ranging from small and simple 8-bit

processors to sophisticated 32-or 64-bit processors.

Input/output interfaces such as serial ports.

Peripherals such as timers and watchdog circuit.

RAM for data storage.

ROM, EEPROM or Flash memory for program storage.

Clock generator – often an oscillator for a quartz timing crystal,

resonator or RC Circuit.

…14…

Most industrial equipments is controller through mechanical or

electrical devices called controllers. These devices helpful for turn on or turn

off various processes and thus they regulate the control of particular

mechanism.

3.3.2 SELECTION OF MICROCONTROLLER:

Speed of operation.

No. of I/O ports required.

Availability of Assembler, Simulator, Compiler, etc.

On chip serial communication.

On chip program memory and data memory.

3.3.3 PIN DESCRIPTION:

VCC (Pin 20) Supply voltage.

GND (Pin 10) Ground.

Port 1 (Pin 12-19)

The Port 1 is an 8-bit bi-directional I/O port. Port pins P1.2 to P1.7

provide internal pull-ups. P1.0 and P1.1 require external pull-ups. P1.0 and

P1.1 also serve as the positive input (AIN0) and the negative input (AIN1),

respectively, of the on-chip precision analog comparator. The Port 1 out-put

buffers can sink 20 mA and can drive LED displays directly. When 1s are

written to Port 1 pins, they can be used as inputs. When pins P1.2 to P1.7 are

used as inputs and are externally pulled low, they will source current (IIL)

because of the internal pull-ups.

…15…

Port 3 (Pin 2,3,6,7,8,9,11)

Port 3 pins P3.0 to P3.5, P3.7 are seven bi-directional I/O pins with

internal pull-ups. P3.6 is hard-wired as an input to the output of the on-chip

comparator and is not accessible as a gen-eral-purpose I/O pin. The Port 3

output buffers can sink 20 mA. When 1s are written to Port 3 pins they are

pulled high by the internal pull-ups and can be used as inputs. As inputs,

Port 3 pins that are externally being pulled low will source current (IIL)

because of the pull-ups.

RST (Pin 1)

Reset input. All I/O pins are reset to 1s as soon as RST goes high. Holding the RST pin high for two machine cycles while the oscillator is running resets the device. Each machine cycle takes 12 oscillator or clock cycles.

XTAL1 (Pin 5)

Input to the inverting oscillator amplifier and input to the internal clock operating circuit.

XTAL2 (Pin 4)

Output from the inverting oscillator amplifier.

…16…

3.3.4 OSCILLATOR CHARACTERISTICS:

The XTAL1 and XTAL2 are the input and output, respectively, of an

inverting amplifier which can be configured for use as an on-chip oscillator,

as shown in Figure 5-1. Either a quartz crystal or ceramic resonator may be

used. To drive the device from an external clock source, XTAL2 should be

left unconnected while XTAL1 is driven as shown in Figure 5-2. There are

no requirements on the duty cycle of the external clock signal, since the

input to the internal clocking circuitry is through a divide-by-two flip-flop,

but minimum and maximum voltage high and low time specifications must

be observed.

Fig.1 Oscillator Connections Fig.2 External Clock Drive Configuration

…17…

3.4 RF TRANSMITTER:

3.4.1 Working:

The RF Transmitter is ideal for remote control application where low

cost and longer range is required. The transmitter operates from 1.5v – 12v

supply, making it ideal for low powered application. The transmitter

employs saw tooth architecture, ensuring accurate frequency control for

best range performance. Output power ND Harmonic emissions are easy to

control. Due to low cost make it suitable for high volume application.

…18…

3.4.2 FEATURE:

Low Cost

On - Off keying/frequency shift keying data format.

Up to 9.6 kbps data rate & Smaller in size.

3.4.3 SIMPLEST RF TRANSMITTER:

This is probably a simplest radio transmitter that you will find

anywhere. It is total of five parts and can be constructed in very small space.

It is great for science fair projects or other science related projects where

short range transmission is useful. It runs on 1.5-3 volts with small hearing

aid batteries. A thermister can be inserted in series with R1 to have varying

output frequency dependent on input. The frequency can also be changed by

changing the value of C1. L1 is 20-30 turns of thin magnet wire closed

around a 1/8 to 1/4 diameter non-conductive form. The coil is tapped 1/3of

the way from one end and tap connect to the emitter of Q1.experiment with

all the values in the circuit. Nothing is critical, but performance can be

varied considerably.

…19…

3.4.4 Transmitter:

Crystal-locked PLL, FM modulated at up to 64 kb/s

Operation from 2.2V to 16V @ 7.5mA

Built-in regulator for improved stability and supply noise rejection

1mW nominal RF output

Enable facility

3.5 IMPLEMENTED RF TRANSMITTER CIRCUIT:

…20…

3.6 RF RECEIVER:

3.6.1 OPERATION:

RF Receiver allows users to easily receive serial data, robot control,

or other information wirelessly. When paired with the matched RF

TRANSMITTER, reliable wireless communication is as effortless as

sending serial data. The power-down (PDN) pin may be used to place the

module into a low power state (active low), or left floating (it is tied high

internally).

Short for Radio Frequency, RF refers to the frequencies that fall

within the electromagnetic spectrum associated with radio wave

propagation. When applied to an antenna.

…21…

RF current creates electromagnetic fields that propagate the applied

signal through space. Any RF field has a wavelength that is inversely

proportional to the frequency. This means that the frequency of an RF signal

is inversely proportional to the wavelength of the field received signal

strength indicator.

This line will supply an analog voltage that is proportional to the strength of

the received signal. When initiating communication between the RF

modules, a sync pulse should be sent to re-establish the radio connection

between the modules. Sending several characters can accomplish this,

however sending a pulse (which maintains a high state during the

synchronization) is more efficient.

Suppose I have a little device capable of emitting a beep sound. It's

just a little box, with a loudspeaker and an on/off switch. When you turn the

switch on, the device emits a continuous beep sound. When you turn the

switch off, the device becomes silent. This device is an emitter. Secondly,

suppose I have another little device capable of hearing the beep sound.

When you turn the emitter switch on, the lamp of the receiver begins

to glow. When you turn the switch of the emitter off, the lamp of the

receiver darkens. And so on. If the receiver has been build a basic way, then

the distance over which the communication works will be a few meters or a

few tens of meters. If you put the receiver, say 50 meters away of the

emitter, then there will be no more communication. When you turn the

switch of the emitter on, the lamp of the receiver will not begin to glow. But,

if you build a long distance receiver, then the Distance may be a lot more

than 50 meters.

…22…

But, after 1 kilometer walking away, the long distance receiver still

manages to hear the sound of the emitter. Amazingly, the communication

works.

A device is added to the receiver to make him listen as much as

possible only to the signal coming from the direction of the emitter. That's

what you do when you put your hands back your ears to hear better a weak

sound. The device best known is again the parabolic antenna, but there are a

lot of other ways to achieve directivity. Like using several antennas and

adding their signals. The bigger the device, the more directivity you get. A

parabolic antenna acts for radio waves just like a solar oven acts for the

sunlight, concentrating what it receives on one given point.

You can imagine for sure that making a receiver work in a noisy

environment reduces its performances. But a receiver also produces its own

"internal noise" every electronic component inside a receiver produces a

noise. That's why those components must be carefully choose or

manufactured to produce the less possible noise.

To decrease even more the remaining amount of noise, and it can

physically not be done another way, the receiver must be cooled down. It

can be plunged into liquid nitrogen or even liquid helium. This is true

whatever the type of communication system you are using: radio waves,

light, light trough fiber optics, sound, electric signals trough wires, even

interstellar gravitational waves.

Inside a simple component like a resistor, the noise is simply due to

the electrons moving around inside the resistor.

…23…

Thus there are two ways to increase the emitted power:

Increase the electric tension of the signal send into the antenna. Just

like a lamp would glow lighter or a loudspeaker would give louder

sound, an antenna will broadcast more powerful radio waves.

Increase the length of the antenna. The more the length is increased,

the littler becomes the impedance. Thus, the more current goes trough

the antenna and the more power is consumed an emitted as radio

waves. If you double the length of the antenna, you half the resistance

and thus you emit two times more power. Attention: once the antenna

becomes longer than half the wave length you get a disturbing

directivity. That's why half the wave length is the common length for

an antenna. Longer Antennas may emit no more power in the

direction of the receiver and thus give the impression they emit less

energy which is false (hence the illusion an antenna is a resonating

device, which is false too).

3.6.2 FEATURES:

High – speed data RECEIVE rates.

SIP header allows for ease of use.

Compatible with all BASIC Stamp modules SX chips.

AS easy to use as simple SEROUT/SERIN PBASIC instruction

Power – down mode for conservative energy usage (longer battery

life)

Line – of – sight range of 500 feet (or greater depending on

conditions)

…24…

3.7 IMPLEMENTER RF RECEIVER CIRCUIT:

…25…

CHAPTER - 4

WIRELESS ENERGY CONTROLL UNIT

A power management system and associated method therefore

includes a plurality of local wireless energy control units at remote sites for

controlling power delivery to customer loads, and a central station with a

wireless transmitter for broadcasting commands to the wireless energy

control units. The wireless energy control units each comprise a bank of

switches for controlling power delivery to electrical loads at each local site.

The controllable switches preferably have a deformable bimetal member

controlled by a heated coil for engaging and disengaging electrical contacts.

Each wireless energy control unit is capable of being pre-configured so as to

specify the order or priority in which electrical loads are disengaged, in

response to commands to reduce power consumption received from the

central station. The central station may issue power reduction commands

according to different priority levels or alert stages. The local wireless

energy units respond to the power reduction commands by disengaging one

or more electrical loads in accordance with the priority level of the power

reduction command, and through their collective operation reduce overall

customer power demand.

A wireless energy control unit, comprising: a plurality of controllable

switches each having a first position wherein a power source is

electronically connected to an electrical load and a second position wherein

the power source is disconnected from the electrical load; a wireless

receiver.

…26…

wherein one or more of said controllable switches comprises: a

deformable member having a first end and a second end, said deformable

member anchored at said first end and residing in contact with an electrical

conductor at said second end; and a heating element in proximity with the

deformable member, said heating element responsive to a switch control

signal from said controller; and wherein an incoming wire drawing power

from said power source is connected to the deformable member at said

second end near the electrical conductor, said incoming wire being

electrically connected to said electrical conductor when the deformable

member resides in contact with the electrical conductor.

A wireless energy control unit, comprising: a plurality of identical

controllable switches each interposed between a power source and one of a

plurality of electrical loads, each controllable switch capable of engaging the

power source with, or disengaging the power source from, the switch's

respective electrical load; user interface means for selecting a priority order

according to which said controllable switches are to be disengaged from

their respective electrical loads in response to messages received from a

remote source; a wireless receiver; and a controller connected to said

wireless receiver, said controller receiving messages via said wireless

receiver and, in response thereto, causing selected ones of said controllable

switches to disengage the power source from, or engage the power source

with, each selected switch's respective electrical load; wherein one or more

of said controllable switches comprises: a deformable member having a first

end and a second end, said deformable member anchored at said first end

and residing in contact with an electrical conductor at said second end; and a

heating element in proximity with the deformable member.

…27…

Where in an incoming wire drawing power from said power source is

connected to the deformable member at said second end near the electrical

conductor, said incoming wire being electrically connected to said electrical

conductor when the deformable member resides in contact with the electrical

conductor.

In one aspect, a local energy control unit includes a set of controllable

switches for controlling power delivery from a power supply line to

individual electrical loads. The energy control unit preferably causes the

controllable switches to engage or disengage their respective electrical loads,

in a configurable order, when an external command is received. The energy

control unit can be user-configured (e.g., programmed) to prioritize the order

in which loads are disengaged. In a preferred embodiment, the controllable

switches are electrically connected in series with (e.g., downstream from) a

set of circuit breakers, and the controllable switches are preferably capable

of selectively disengaging and re-engaging electrical loads as may be

present, for example, at commercial or residential electrical outlets, while

drawing little or no power when conducting.

In a particular context, wireless energy control units may be utilized

within an energy management system, and placed at various remote

customer sites for controlling energy distribution to local electrical loads. A

user may pre-configure the energy control unit to specify the order or

priority in which electrical loads are disengaged, in response to commands

to reduce energy consumption. A wireless command system allows the

energy control units to receive commands from a distant location.

…28…

CHAPTER - 5

RADIO FREQUENCY IDENTIFICATION

The object of any RFID system is to carry data in suitable

transponders, generally known as tags, and to retrieve data, by machine-

readable means, at a suitable time and place to satisfy particular application

needs. Data within a tag may provide identification for an item in

manufacture, goods in transit, a location, the identity of a vehicle, an animal

or individual. By including additional data the prospect is provided for

supporting applications through item specific information or instructions

immediately available on reading the tag. For example, the color of paint for

a car body entering a paint spray area on the production line, the set-up

instructions for a flexible manufacturing cell or the manifest to accompany a

shipment of goods.

A system requires, in addition to tags, a means of reading or

interrogating the tags and some means of communicating the data to a host

computer or information management system. A system will also include a

facility for entering or programming data into the tags, if this is not

undertaken at source by the manufacturer. Quite often an antenna is

distinguished as if it were a separate part of an RFID system. While its

importance justifies the attention it must be seen as a feature that is present

in both readers and tags, essential for the communication between the two.

…29…

5.1 WIRELESS COMMUNICATION AND THE AIR

INTERFACE:

Transmitting data is subject to the vagaries and influences of the

media or channels through which the data has to pass, including the air

interface. Noise, interference and distortion are the sources of data

corruption that arise in practical communication channels that must be

guarded against in seeking to achieve error free data recovery. To transfer

data efficiently via the air interface or space that separates the two

communicating components requires the data to be superimposed upon a

rhythmically varying (sinusoidal) field or carrier wave. This process of

superimposition is referred to as modulation, and various schemes are

available for these purposes, each having particular attributes that favor their

use. They are essentially based upon changing the value of one of the

primary features of an alternating sinusoidal source, its amplitude, frequency

or phase in accordance with the data carrying bit stream. In addition to non-

contact data transfer, wireless communication can also allow non-line-of-

sight communication. However, with very high frequency systems more

directionality is evident and can be tailored to needs through appropriate

antenna design.

5.2 CARRIER FREQUENCIES:

In wired communication systems the physical wiring constraints allow

communication links and networks to be effectively isolated from each

other.

...30…

The approach that is generally adopted for radio frequency

communication channels is to separate on the basis of frequency allocation.

This requires, and is generally covered by government legislation, with

different parts of the electromagnetic spectrum being assigned to different

purposes. Allocations may differ depending on the governments concerned,

requiring care in considering RFID applications in different countries.

Standardization efforts are seeking to obviate problems in this respect.

Three frequency ranges are generally distinguished for RFID systems,

low, intermediate (medium) and high. The following table summarizes these

three frequency ranges, along with the typical system characteristics and

examples of major areas of application.

Frequency Bands and Applications

Frequency Band Characteristics Typical Applications

Low 100-500 kHz Short to medium read

range Inexpensive low

reading speed

Access control Animal

identification Inventory

control Car immobilizer

Intermediate 10-15

MHz

Short to medium read

range potentially

inexpensive medium

reading speed

Access control Smart

cards

High 850-950 MHz 2.4-

5.8 GHz

Long read range High

reading speed Line of

sight required

Expensive

Railroad car monitoring

Toll collection systems

…31…

A degree of uniformity is being sought for carrier frequency usage,

through three regulatory areas, Europe and Africa (Region 1), North and

South America (Region 2) and Far East and Australasia (Region 3). Each

country manages their frequency allocations within the guidelines set out by

the three regions. Unfortunately, there has been little or no consistency over

time with the allocation of frequency, and so there are very few frequencies

that are available on a global basis for the technology. This will change with

time, as countries are required to try to achieve some uniformity by the year

2010.

5.3 DATA TRANSFER RATE AND BANDWIDTH:

Choice of field or carrier wave frequency is of primary importance in

determining data transfer rates. In practical terms the rate of data transfer is

influenced primarily by the frequency of the carrier wave or varying field

used to carry the data between the tag and its reader. Generally speaking the

higher the frequency the higher the data transfer or throughput rates that can

be achieved. This is intimately linked to bandwidth or range available within

the frequency spectrum for the communication process.

5.4 DATA CARRYING OPTIONS:

Data stored in data carriers invariable require some organization and

additions, such as data identifiers and error detection bits, to satisfy recovery

needs. This process is often referred to as source encoding. Standard

numbering systems, such as UCC/EAN and associated data defining

elements may also be applied to data stored in tags.

…32…

Basically, tags may be used to carry:

Identifiers, in which a numeric or alphanumeric string is stored for

identification purposes or as an access key to data stored elsewhere

in a computer or information management system.

Portable data files, in which information can be organized, for

communication or as a means of initiating actions without recourse

to, or in combination with, data stored elsewhere.

In terms of data capacity tags can be obtained that satisfy needs from

single bit to kilobits. The single bit devices are essentially for surveillance

purposes. Retail electronic article surveillance (EAS) is the typical

application for such devices, being used to activate an alarm when detected

in the interrogating field. They may also be used in counting applications.

Devices characterized by data storage capacities up to 128 bits are

sufficient to hold a serial or identification number together, possibly, with

parity check bits. Such devices may be manufacturer or user programmable.

Tags with data storage capacities up to 512 bits, are invariably user

programmable, and suitable for accommodating identification and other

specific data such as serial numbers, package content, key process

instructions or possibly results of earlier interrogation/response transactions.

Tags characterized by data storage capacities of around 64 kilobits

may be regarded as carriers for portable data files. With increased capacity

the facility can also be provided for organizing data into fields or pages that

may be selectively interrogated during the reading process.

…33…

5.6 STANDARDIZATION:

If the unique advantages and flexibility of RFID is the good news,

then the proliferation of incompatible RFID standards is the corresponding

bad news. All major RFID vendors offer proprietary systems, with the result

that various applications and industries have standardized on different

vendors’ competing frequencies and protocols. The current state of RFID

standards is severe disarray - standards based on incompatible RFID systems

exist for rail, truck, air traffic control, and tolling authority usage. The US

Intelligent Transportation System and the US Department of Defense (DOD)

Total Asset Visibility system are among other special-interest applications.

The lack of open systems interchangeability has severely crippled

RFID industry growth as a whole, and the resultant technology price

reductions that come with broad-based inter-industry use. However, a

number of organizations have been working to address and hopefully bring

about some commonality among competing RFID systems, both in the U.S.

and in Europe where RFID has made greater market inroads. Meanwhile in

the U.S.A., ANSI’s X3T6 group, comprising major RFID manufacturers and

users, is currently developing a draft document based systems’ operation at a

carrier frequency of 2.45 GHz, which it is seeking to have adopted by ISO.

ISO has already adopted international RFID standards for animal tracking,

ISO 11784 and 11785.

Radio Frequency (RF) refers specifically to the electromagnetic field,

or radio wave, that is generated when an alternating current is input to an

antenna. This field can be used for wireless broadcasting.

…34…

CHAPTER - 6

POWER SUPPLY REQUIRMENTS

Modules incorporate a built-in regulator which delivers a constant

2.8V to the module circuitry when the external supply voltage is 2.85V or

greater, with 40dB or more of supply ripple rejection. This ensures constant

performance up to the maximum permitted supply rail and removes the need

for external supply decoupling except in cases where the supply rail is

extremely poor (ripple/noise content >0.1Vp-p).

Note, however, that for supply voltages lower than 2.85V the

regulator is effectively inoperative and supply ripple rejection is

considerably reduced. Under these conditions the ripple/noise on the supply

rail should be below 10mVp-p to avoid problems. If the quality of the supply

is in doubt, it is recommended that a 10μF low-ESR tantalum or similar

capacitor be added between the module supply pin (Vcc) and ground,

together with a 10Ω series feed resistor between the Vcc pin and the supply

rail. The Enable pin allows the module to be turned on or off under logic

control with a constant DC supply to the Vcc pin. The module current in

power-down mode is less than 1μA.

NOTE: If this facility is used, the logic control signal must have a

slew rate of 40mV/μs or more. Slew rates less than this value may cause

erratic operation of the on-board regulator and therefore the module itself.

It incorporates a low voltage shutoff circuit which prevents any

possibility of erratic operation by disabling the RF output if the supply

voltage drops below 2.2V (±5%). This feature is self-resetting.

…35…

6.1 EXPECTED RANGE:

Predicting the range obtainable in any given situation is notoriously

difficult since there are many factors involved. The main ones to consider

are as follows:

Type and location of antennas in use

Type of terrain and degree of obstruction of the link path

Sources of interference affecting the receiver

Dead spots caused by signal reflections from nearby conductive

objects

Data rate and degree of filtering employed

Assuming the maximum 64kbps data rate and unobstructed ¼-wave whip

antennas on transmitter and receiver, the following ranges may be used as a

rough guide only:

1) Cluttered/obstructed environment, e.g. inside a building: 25-75m

2) Open, relatively unobstructed environment: 100-300m

It must be stressed that range obtained in practice may lie outside

these figures. Range tests should always be performed before assuming that

a particular range can be achieved in any given application.

6.2 ANTENNA CONSIDERATIONS AND OPTIONS:

The choice and positioning of transmitter and receiver antennas is of

the utmost importance and is the single most significant factor in

determining system range. The following notes apply particularly to integral

antennas and are intended to assist the user in choosing the most effective

arrangement for a given application.

…36…

However this is often not desirable for practical/ergonomic reasons

and a compromise may need to be reached. If an internal antenna must be

used try to keep it away from other metal components and pay particular

attention to the “hot” end (i.e. the far end), as this is generally the most

susceptible to detuning. The space around the antenna is as important as the

antenna itself.

Microprocessors and microcontrollers tend to radiate significant

amounts of radio frequency hash, which can cause desensitization of the

receiver if its antenna is in close proximity. 900MHz region is generally less

prone to this effect than lower frequencies, but problems can still arise.

Things become worse as logic speeds increase, because fast logic edges are

capable of generating harmonics across the UHF range which are then

radiated effectively by the PCB tracking. In extreme cases system range can

be reduced by a factor of 3 or more. To minimize any adverse effects, situate

the antenna and module as far as possible from any such circuitry and keep

PCB track lengths to the minimum possible. A ground plane can be highly

effective in cutting radiated interference and its use is strongly

recommended.

A simple test for interference is to monitor the receiver RSSI output

voltage, which should be the same regardless of whether the microcontroller

or other logic circuitry is running or in reset.

Integral antennas generally do not perform as well as externally

mounted types, however they result in physically compact equipment and

are the preferred choice for portable applications. The following can be

recommended.

…37…

Helical: This is a compact but slightly less effective antenna formed

from a coil of wire. It is very efficient for its size, but has high Q and tends

to suffer badly from detuning caused by proximity to nearby conductive

objects. It needs to be carefully trimmed for best performance in a given

situation and the required dimensional tolerances can be difficult to achieve

repeatable, nevertheless it can provide a very compact solution.

Loop: A loop of PCB track, tuned and matched with 2 capacitors.

Loops are relatively inefficient but have good immunity to proximity

detuning, so may be preferred in shorter range applications where very high

component packing density is necessary.

External antennas have several advantages if portability is not an

issue. They can be optimized for individual circumstances and may be

mounted in relatively good RF locations away from sources of interference,

being connected to the equipment by coax feeder. Apart from the usual

whips, helicals etc, low-profile types such as microstrip patches can be very

effective at these frequencies. Suitable antennas are available from many

different sources and are generally supplied pre-tuned to the required

frequency.

…38…

Integral Antenna Configuration

…39…

CHAPTER - 7

OTHER COMPONENTS

ATMEL 553(AT24C08A)

Voltage Regulator IC 7805

Crystal Oscillator

Transistor

Resistor

Capacitor

Zener Diode

…40…

7.1 ATMEL 553(AT24C08A):

7.1.1 DESCRIPTION:

The AT24CO8A provides 8192 bits of serial electrically erasable and

programmable read only memory (EEPROM) organized as 1024 words of 8

bits each. The device iss optimized for use in many industrial and

commercial applications where the low power and the low voltage operation

are essential. The AT24CO8A is available in space saving 8 pin PDIP is

accessed via 2 wire serial interface. In addition, the entire family is available

in 1.8 volt - 5.0 volt versions.

…41…

7.1.2 PIN DESCRIPTION:

Serial Clock (SCL):

The SCL input is used to positive edge clock data in to each EEPROM device and negative edge clock data out of each device.

Serial Data (SDA):

The SDA pin is bi-directional for serial data transfer. This pin is open

drain driven and may be wire – ORed with any number of other open drain

or open collector device.

Device/Page Address (A2, A1, A0):

The A2, A1, A0 pins are device addresses input, for the AT24CO8A only used A2 input for hard wire addressing and total of two 8k device may be addressed on single bus system. The A0 and A1 pins are no connects.

Write Protect (WP):

AT24CO8A has a Write Protect pin that provides hardware data protection. Write Protect pin allows normal read/operation when connected to ground (GND).

7.1.3 FEATURES OF ATMEL 553:

Utilize different array protection compare to the other type IC’s.

Automotive grade and extended temperature device.

Low power and low voltage operation

Bidirectional data transfer protocol.

High reliability.

…42…

7.2 VOLTAGE REGULATOR (IC 7805):

A voltage regulator is an electrical regulator designed to automatically

maintain a constant voltage level.

It may use an electromechanical mechanism, or passive or active

electronic components. Depending on the design, it may be used to regulate

one or more AC or DC voltages.

With the exception of shunt regulators, all modern electronic voltage

regulators operate by comparing the actual output voltage to some internal

fixed reference voltage. Any difference is amplified and used to control the

regulation element. This forms a negative feedback servo control loop. If the

output voltage is too low, the regulation element is commanded to produce a

higher voltage. For some regulators if the output voltage is too high, the

regulation element is commanded to produce a lower voltage; however,

many just stop sourcing current and depend on the current draw of whatever

it is driving to pull the voltage back down. In this way, the output voltage is

held roughly constant. The control loop must be carefully designed to

produce the desired tradeoff between stability and speed of response.

…43…

common

I/P O/P

7.3 CRYSTAL OSCILLATOR:

A crystal oscillator is an electronic circuit that uses the mechanical

resonance of a vibrating crystal of piezoelectric material to create an

electrical signal with a very precise frequency. This frequency is commonly

used to keep track of time (as in quartz wristwatches), to provide a stable

clock signal for digital integrated circuits, and to stabilize frequencies for

radio transmitters.

t

A miniature 4 MHz quartz crystal enclosed in an hermetically sealed

HC-49/US package, used as the resonator in a crystal oscillator.

A crystal is a solid in which the constituent atoms, molecules, or ions

are packed in a regularly ordered, repeating pattern extending in all three

spatial dimensions. Almost any object made of an elastic material could be

used like a crystal, with appropriate transducers, since all objects have

natural resonant frequencies of vibration. For example, steel is very elastic

and has a high speed of sound. It was often used in mechanical filters before

quartz. The resonant frequency depends on size, shape, elasticity, and the

speed of sound in the material.

…44…

Low-frequency crystals, such as those used in digital watches, are

typically cut in the shape of a tuning fork. For applications not needing very

precise timing, a low-cost ceramic resonator is often used in place of a

quartz crystal.

When a crystal of quartz is properly cut and mounted, it can be made

to distort in an electric field by applying a voltage to an electrode near or on

the crystal. This property is known as piezoelectricity. When the field is

removed, the quartz will generate an electric field as it returns to its previous

shape, and this can generate a voltage. The result is that a quartz crystal

behaves like a circuit composed of an inductor, capacitor and resistor, with a

precise resonant frequency. (See RLC circuit.)

Quartz has the further advantage that its elastic constants and its size

change in such a way that the frequency dependence on temperature can be

very low. The specific characteristics will depend on the mode of vibration

and the angle at which the quartz is cut (relative to its crystallographic axes)1

Therefore, the resonant frequency of the plate, which depends on its size,

will not change much, either. This means that a quartz clock, filter or

oscillator will remain accurate. For critical applications the quartz oscillator

is mounted in a temperature-controlled container, called a crystal oven, and

can also be mounted on shock absorbers to prevent perturbation by external

mechanical vibrations. Quartz timing crystals are manufactured for

frequencies from a few tens of kilohertz to tens of megahertz. More than two

billion (2×109) crystals are manufactured annually. Most are small devices

for consumer devices such as wristwatches, clocks, radios, and cell phones.

…45…

7.4 TRANSISTOR:

A transistor is a three-terminal semiconductor device that can be used

for amplification, switching, voltage stabilization, signal modulation and

many other functions. The transistor is the fundamental building block of

both digital and analog integrated circuits — the circuitry that governs the

operation of computers, cellular phones, and all other modern electronics.

7.4.1 INTRODUCTION:

Transistors are divided into two main categories: bipolar junction

transistors (BJTs) and field effect transistors (FETs). Application of current

in BJTs and voltage in FETs between the input and common terminals

increases the conductivity between the common and output terminals,

thereby controlling current flow between them. For more details on the

operation of these two types of transistors, see field effect transistor and

bipolar junction transistor. In analog circuits, transistors are used in

amplifiers, (direct current amplifiers, audio amplifiers, radio frequency

amplifiers), and linear regulated power supplies. Transistors are also used in

digital circuits where they function as electronic switches.

7.4.2 IMPORTANCE:

The transistor is considered by many to be one of the greatest

inventions in modern history, ranking in importance with the printing press,

automobile and telephone.

…46…

It is the key active component in practically all modern electronics.

Its importance in today's society rests on its ability to be mass produced

using a highly automated process (fabrication) that achieves vanishingly low

per-transistor costs.

Although millions of individual (known as discrete) transistors are

still used, the vast majority of transistors are fabricated into integrated

circuits (often abbreviated as IC and also called microchips or simply chips)

along with diodes, resistors, capacitors and other electronic components to

produce complete electronic circuits. A logic gate comprises about twenty

transistors whereas an advanced microprocessor, as of 2006, can use as

many as 1.7 billion transistors (MOSFETs) .The transistor's low cost,

flexibility and reliability have made it a universal device for non-mechanical

tasks, such as digital computing. Transistorized circuits have replaced

electromechanical devices for the control of appliances and machinery as

well. It is often less expensive and more effective to use a standard

microcontroller and write a computer program to carry out a control function

than to design an equivalent mechanical control function.

Because of the low cost of transistors and hence digital computers,

there is a trend to digitize information. With digital computers offering the

ability to quickly find, sort and process digital information, more and more

effort has been put into making information digital. As a result, today, much

media data is delivered in digital form, finally being converted and presented

in analog form by computers. Areas influenced by the Digital Revolution

include television, radio, and newspapers.

…47…

7.4.3 SEMICONDUCTOR MATERIAL:

The first BJTs were made from germanium (Ge) and some high power

types still are. Silicon (Si) types currently predominate but certain advanced

microwave and high performance versions now employ the compound

semiconductor material gallium arsenide (GaAs) and the semiconductor

alloy silicon germanium (SiGe). Single element semiconductor material (Ge

and Si) is described as elemental.

Semiconductor material

Junction forwardvoltageV @ 25 °C

Electron mobilitym/s @ 25 °C

Hole mobility

m/s @ 25°C

Max.junction temp.°C

Ge 0.27 0.39 0.19 70 to 100

Si 0.71 0.14 0.05

150 to 200GaAs 1.03 0.85 0.05 150 to 200

Al–Si junction

0.03 — — 150 to 200

…48…

7.5 RESISTOR:

Electrical resistance is a measure of the degree to which an object

opposes an electric current through it, measured in ohms. Its reciprocal

quantity is electrical conductance measured in siemens. Assuming a uniform

current density, an object's electrical resistance is a function of both its

physical geometry and the resistivity of the material it is made from:

Where,

"l" is the length

"A" is the cross sectional area, and

"ρ" is the resistivity of the material

Electrical resistance shares some conceptual parallels with the

mechanical notion of friction. The SI unit of electrical resistance is the ohm,

symbol Ω. The resistance of an object determines the amount of current

through the object for a given potential difference across the object.

For a wide variety of materials and conditions, the electrical resistance

does not depend on the amount of current through or the amount of voltage

across the object, meaning that the resistance R is constant.

…49…

7.6 CAPACITOR:

A capacitor is an electrical device that can store energy in the electric

field between a pair of conductors (called "plates"). The process of storing

energy in the capacitor is known as "charging", and involves electric charges

of equal magnitude, but opposite polarity, building up on each plate.

Capacitors are often used in electrical circuit and electronic circuits as

energy-storage devices. They can also be used to differentiate between high-

frequency and low-frequency signals. This property makes them useful in

electronic filters.

Capacitors are occasionally referred to as condensers. This is

considered an antiquated term in English, but most other languages use an

equivalent, like "Kondensator" in German.

7.6.1 CAPACITANCE:

The capacitor's capacitance (C) is a measure of the amount of charge

(Q) stored on each plate for a given potential difference or voltage (V) which

appears between the plates.

In SI units, a capacitor has a capacitance of one farad when one

coulomb of charge is stored due to one volt applied potential difference

across the plates. Since the farad is a very large unit, values of capacitors are

usually expressed in microfarads (µF), nanofarads (nF), or picofarads (pF).

…50…

When there is a difference in electric charge between the plates, an

electric field is created in the region between the plates that is proportional

to the amount of charge that has been moved from one plate to the other.

This electric field creates a potential difference V = E·d between the plates of

this simple parallel-plate capacitor.

The capacitance is proportional to the surface area of the conducting

plate and inversely proportional to the distance between the plates. It is also

proportional to the permittivity of the dielectric (that is, non-conducting)

substance that separates the plates.

7.6.2 STORED ENERGY:

As opposite charges accumulate on the plates of a capacitor due to the

separation of charge, a voltage develops across the capacitor due to the

electric field of these charges. Ever-increasing work must be done against

this ever-increasing electric field as more charge is separated. The energy

(measured in joules, in SI) stored in a capacitor is equal to the amount of

work required to establish the voltage across the capacitor, and therefore the

electric field.

The maximum energy that can be (safely) stored in a particular

capacitor is limited by the maximum electric field that the dielectric can

withstand before it breaks down. Therefore, all capacitors made with the

same dielectric have about the same maximum energy density (joules of

energy per cubic meter).

…51…

7.7 ZENER DIODE:

A Zener diode is a type of diode that permits current to flow in the

forward direction like a normal diode, but also in the reverse direction if the

voltage is larger than the breakdown voltage known as "Zener knee voltage"

or "Zener voltage". Named for Clarence Zener, discoverer of this electrical

property.

A conventional solid-state diode will not let significant current flow if

it is reverse-biased below its reverse breakdown voltage. When the reverse

bias breakdown voltage is exceeded, a conventional diode is subject to high

current flow due to avalanche breakdown. Unless this current is limited by

external circuitry, the diode will be permanently damaged. In case of large

forward bias (current flow in the direction of the arrow), the diode exhibits a

voltage drop due to its junction built-in voltage and internal resistance. The

amount of the voltage drop depends on the semiconductor material and the

doping concentrations. A Zener diode exhibits almost the same properties,

except the device is specially designed so as to have a greatly reduced

breakdown voltage, the so-called Zener voltage. A Zener diode contains a

heavily doped p-n junction allowing electrons to tunnel from the valence

band of the p-type material to the conduction band of the n-type material. In

the atomic model, this tunneling corresponds to the ionization of covalent

bonds. The Zener effect was discovered by physicist Clarence Melvin Zener.

A reverse-biased Zener diode will exhibit a controlled breakdown and let the

current flow to keep the voltage across the Zener diode at the Zener voltage.

…52…

The breakdown voltage can be controlled quite accurately in the

doping process. Tolerances to within 0.05% are available though the most

widely used tolerances are 5% and 10%.

Another mechanism that produces a similar effect is the avalanche

effect as in the avalanche diode. The two types of diode are in fact

constructed the same way and both effects are present in diodes of this type.

In silicon diodes up to about 5.6 volts, the zener effect is the predominant

effect and shows a marked negative temperature coefficient. Above 5.6

volts, the avalanche effect becomes predominant and exhibits a positive

temperature coefficient.

7.7.1 USES:

Zener diodes are widely used to regulate the voltage across a circuit.

When connected in parallel with a variable voltage source so that it is

reverse biased, a zener diode conducts when the voltage reaches the diode's

reverse breakdown voltage. From that point it keeps the voltage at that

value.

…53…

CHAPTER - 8

ADVANTAGES

Combined hardware & software package used for automated monitoring.

Energy data is presented in a clear format which highlights west full practices & areas for improved energy efficiency.

Easy to use energy reporting tool that allows daily, weekly & weekly energy cost consumption to be analyzed.

Smart automated processes instead of manual work.

Accurate information from the network load to optimize maintenance and investments.

Customize rates and billing dates.

Better network performance and cost efficiency & Theft identification.

BENEFITS OF WIRELESS ENERGY METER:

Ability to detect tamper events and outage occurrence.

Calculate transformer loading and sizing from interval data.

Interval data gives accurate load information for supply scheduling,

switching operation, planning, etc.

Monitor voltage at each premise to know conditions when to operate

switches and regulators.

Consistent and granular data for improved accuracy.

…54…

CHAPTER - 9

LIMITATIONS

Noise interference & distortion are the sources of data corruption.

Required high frequency system.

High frequency system is hazardous for human life.

Appropriate antenna design.

…55…

CHAPTER - 10

APPLICATIONS

Lower Cost RF solutions replace expensive hardwiring, greatly

reducing the high costs of cable installation or retrofitting.

Less Environmental Impact RF eliminates the environmentally-

invasive damage of laying cable while reducing investments in

reconstruction.

System Protection RF allows for isolation of sensitive equipment,

reducing the chances of failure due to power surges or severed cables.

Greater Flexibility Equipment is no longer physically tied down. RF

enables easy relocation within a building or outdoors without

rewiring.

Ideal for sharp monitoring studies of individual machines.

Can be used for monitoring electrical energy consumes.

Can incorporate production data for process management &

production efficiency.

Consumption & monitoring.

Billing & payment.

Conservation & loss management.

Machine health monitoring.

…56…

CHAPTER - 11

CONCLUSION

Wireless communication is implemented, so that the consumed energy

information can be transmitted to a centralized monitoring station

through a F.M. transmitter & FM receiver.

Design a perfect system which helps to overcome from the problem of

tampering of meter, faulty reading & poor metering efficiency.

The present invention relates to improving the accuracy and reliability

of transmission of free-space optical digital communication signals.

More particularly, the present invention is directed to a system and

method for synchronizing transmitted optical digital communication

signals by simultaneously transmitting a radio frequency timing

signal.

…57…

CHAPTER - 12

FUTURE SCOPE

If consumer may try to tamper the meter by shorting the relay

contacts, the receiver receives more pulse than the credit, immediately

alarm energizes at receiver.

The energy data management system with energy theft identification.

Robust enclosures can be mounted inside or outside building.

Energy software to plot record and analysis energy consumption.

Can develop in to prepaid electronic energy meter.

…58…

CHAPTER - 13

REFRENCES

L-Li, Ju Halpem, “Wireless Energy Meter, concepts & applications”

ICC-2001, IEEE International conference on 2001.

A.R. Al-Ali, “Wireless Distributed Energy Billing System” Page no.

202-207, International journal of computers & applications 2006.

V.Rodople, T.H. Meng, “Minimum Energy Mobile Wireless

Networks”, IEEE Journal on selected areas in communications 1999.

S.R.Gandham, M.Dawande, R.Prakash, S.Venkatesan, “ Energy

Efficient Schemes For Wireless Energy Meter”, IEEE

Telecommunication conference 2003.

Integration Associates, Inc. Integration IEEE 802.15.4/Zig Bee TM

USB Dongle IA OEMDAUB12400. Datasheet. Internet,

http://www.integration.com/docs/IA_OEMDSUB1_ 2400.pdf. 2006.

Zig Bee Alliance. Zig Bee Specification. v1.0. Internet,

http://www.zigbee.org. 2004.

IEEE. IEEE 802.11g-2003. Telecommunications and information

exchange between systems—Local and metropolitan area networks—

Specific requirements—Part 11: Wireless LAN Medium Access

Control (MAC) and Physical Layer (PHY) specifications—

Amendment.

…59…

Further Higher-Speed Physical Layer Extension in the 2.4 GHz Band.

2003.

B.Rizvi, “A 900 MHz/1.8-GHz CMOS for dual band applications,”

Dig. Technical papers.pp.128-131, June 1998.

T. Yamawaki et ai,“A 2.7-V GSM RF Transceiver JC”, IEEE Journal

of solid-state circuits, Vol. 32, PP. 2089-2096, Dec. 1997.

Universal Serial Bus Revision 2.0 specification. Internet, 2006.

…60…

IMPLEMENTED MODEL FOR WIRELESS

ENERGY METER