Automatic Power Saving1 PIC NEW 11111

ABSTRACT

Power saving device is an ideal system that not only maintains

comfort but also saves your power and money supply. It also comes with an

in built automatic programmer, which gives positive economical

performance by saving electricity and also comes with micro controller

technology in which there is no inconvenience of switching the AC ‘ON’

and ‘OFF’. It provides built in energy saving on/off auto programmable

timer from one minute to 24 hours with digital display and comes with delay

timer and auto restart too.

Power saving devices are easy to install, avoids additional switching

arrangement, saves electricity and reduces maintenance thus improving the

life of the instrument. It is ideal for windows, split ac, package units and

other such applications. Indeed a device, which saves energy and recovers,

cost in few months.

INTRODUCTION

The present invention relates to an automatic power- saving device

which is capable of automatically interrupting the supply of electric power

when electricity is not in use in wired sections between a power distributing

board and receptacles or cord sections between the receptacles and electric

appliances, thereby saving power at a standby state and preventing the

occurrence of a fire.

This project is hardware based project in which, electric power is

saving through the MICROCONTROLLER.

This circuit contains 2 IR Transreceivers, Microcontroller, Relay

driver circuit, Relay, 16*2 Model LCD screen, 0808 ADC, LDR and

temperature sensor.

In this type of circuit, 2 IR sensors are connected to microcontroller

which is placed near the Gate, between these two IR sensor, length us about

20-25 cm. When the person is enter then IR sensor get effected and IR

sensor is get effected when any person get exit. There are three Relays

which they are connected to Microcontroller, throughout Relay driver which

is capable to drive the current of relay. In this circut Relay 1 is get connected

to the main line of power supply. Relay 2 is connectd to the Heater of AC.

Relay 3 is connected to the porch/pole lamp. 1 ADC is connected to the

Microcontroller which is given the Analog value of temperature.

We can quickly make the relay on/off using keypad for local

operation. To indicate the status of relay, LED indicator is used.

Additional Function :

A specific key is allocated for all Relay’s ON,

Second specific key is allocated for all Relay’s OFF.

Block DIA.

COMPONENT LIST & DESCRIPTION

3.2768MHz crystal (X1) 1

2-line 16 characters (per line)alphanumeric LCD (optional – see text) (X2) 1

4-way pin header , 1mm pitch (TB1) 1

10-way pin header and connector, 1mm pitch (TB2) 1

8-pin DIL socket 1

28-pin DIL socket 1

Nylon self-adhesive PCB mounting pillars 4

Semiconductors

1N4148 signal diodes (D1, D4) 4

15V 400mA Zener diodes (D2, D3) 2

W005-type 50V 1A bridge rectifier (REC1) 1

BC549 NPN transistor (TR1) 1

PIC16F877A micro controller, 1

78L05 +5V 100mA voltage regulator (IC3) 1

Capacitors

10pF ceramic, 0.2in pitch (C2,C3) 2

100nF ceramic, 2.0in pitch (C1, C6 to C8, C11, C13) 6

22mF 25V radial elect. (C5, C10, C12, C14) 4

470mF 25V radial elect. (C4, C9) 2

Resistors (0.25W, 1% carbon film)

100W (R11) 1

220W (R9, R10) 2

1kW (R1, R8) 2

10kW (R2 to R7, R14 to R16) 9

100kW (R12) 1

220kW (R14) 1

10kW min. round carbon preset potentiometers 2

Microcontroller PIC16F877A

High-Performance RISC CPU:

•Only 35 single-word instructions to learn

•All single-cycle instructions except for program branches, which are two-cycle

•Operating speed:DC – 20 MHz clock input DC – 200 ns instruction cycle

•Up to 8K x 14 words of Flash Program Memory,

Up to 368 x 8 bytes of Data Memory (RAM),

Up to 256 x 8 bytes of EEPROM Data Memory

•Pinout compatible to other 28-pin or 40/44-pin

Peripheral Features:

•Timer0: 8-bit timer/counter with 8-bit prescaler

•Timer1: 16-bit timer/counter with prescaler, can be incremented during Sleep via external

crystal/clock

•Timer2: 8-bit timer/counter with 8-bit period register, prescaler and postscaler

•Two Capture, Compare, PWM modules

-Capture is 16-bit, max. resolution is 12.5 ns

-Compare is 16-bit, max. resolution is 200 ns

-PWM max. resolution is 10-bit

•Synchronous Serial Port (SSP) with SPI™ (Master mode) and I2C™ (Master/Slave)

•Universal Synchronous Asynchronous Receiver Transmitter (USART/SCI) with 9-bit address

detection

•Parallel Slave Port (PSP) – 8 bits wide with external RD, WR and CS controls (40/44-pin only)

•Brown-out detection circuitry for Brown-out Reset (BOR)

Analog Features:

•10-bit, up to 8-channel Analog-to-Digital

Converter (A/D)

•Brown-out Reset (BOR)

•Analog Comparator module with:

-Two analog comparators

-Programmable on-chip voltage reference

(VREF) module

-Programmable input multiplexing from device

inputs and internal voltage reference

-Comparator outputs are externally accessible

Special Microcontroller Features:

•100,000 erase/write cycle Enhanced Flash

program memory typical

•1,000,000 erase/write cycle Data EEPROM memory typical

•Data EEPROM Retention > 40 years

•Self-reprogrammable under software control

•In-Circuit Serial Programming™ (ICSP™) via two pins

•Single-supply 5V In-Circuit Serial Programming

•Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation

•Programmable code protection

•Power saving Sleep mode

•Selectable oscillator options

•In-Circuit Debug (ICD) via two pins

CMOS Technology:

•Low-power, high-speed Flash/EEPROM technology

•Fully static design

•Wide operating voltage range (2.0V to 5.5V)

•Commercial and Industrial temperature ranges

•Low-power consumption

DEVICE OVERVIEW

This document contains device specific information about the following devices:

•PIC16F873A

•PIC16F874A

•PIC16F876A

•PIC16F877A

PIC16F873A/876A devices are available only in 28-pin packages, while PIC16F874A/877A

devices are available in 40-pin and 44-pin packages. All devices in the PIC16F87XA family share

common architecture withthe following differences:

•The PIC16F873A and PIC16F874A have one-half of the total on-chip memory of the

PIC16F876A and PIC16F877A

•The 28-pin devices have three I/O ports, while the 40/44-pin devices have five

•The 28-pin devices have fourteen interrupts, while the 40/44-pin devices have fifteen

•The 28-pin devices have five A/D input channels, while the 40/44-pin devices have eight

•The Parallel Slave Port is implemented only on the 40/44-pin devices

The available features are summarized in Table1-1. Block diagrams of the PIC16F873A/876A

and PIC16F874A/877A devices are provided in Figure1-1 and Figure1-2, respectively. The

pinouts for these device families are listed in Table1-2 and Table1-3. Additional information may

be found in the PICmicro® Mid-Range Reference Manual (DS33023), which may be obtained

from your local Microchip Sales Representative or downloaded from the Microchip web site. The

Reference Manual should be considered a complementary document to this data sheet and is

highly recom-

mended reading for a better understanding of the device architecture and operation of the

peripheral modules.

MEMORY ORGANIZATION

There are three memory blocks in each of the PIC16F87XA devices. The program

memory and data memory have separate buses so that concurrent access can occur and is detailed

in this section. The EEPROM data memory block is detailed in Section3.0 “Data EEPROM and

Flash Program Memory”. Additional information on device memory may be found in the

PICmicro®

Status Register

The Status register contains the arithmetic status of the ALU, the Reset status and the

bank select bits for data memory. The Status register can be the destination for any instruction, as

with any other register. If the Status register is the destination for an instruction that affects the Z,

DC or C bits, then the write to these three bits is disabled. These bits are set or cleared according

to the device logic. Furthermore, the TO and PD bits are not writable, therefore, the result of an

instruction with the Status register as destination may be different than intended

Status Register

The Status register contains the arithmetic status of the ALU, the Reset status and the

bank select bits for data memory. The Status register can be the destination for any

instruction, as with any other register. If the Status register is the destination for an

instruction that affects the Z, DC or C bits, then the write to these three bits is disabled.

These bits are set or cleared according to the device logic. Furthermore, the TO and PD

bits are not writable, therefore, the result of an instruction with the Status register as

destination may be different than intended. For example, CLRF STATUS, will clear the

upper three bits and set the Z bit. This leaves the Status register as 000u u1uu (where u =

unchanged). It is recommended, therefore, that only BCF, BSF, SWAPF and MOVWF

instructions are used to alter the

Status register because these instructions do not affect the Z, C or DC bits from the Status

register. For other instructions not affecting any status bits, see

Regulator LM78L05

General Description

The LM78XX series of three terminal regulators is available with

several fixed output voltages making them useful in a wide range of

applications One of these is local on card regulation eliminating the

distribution problems associated with single point regulation The voltages

available allow these regulators to be used in logic systems instrumentation

HiFi and other solid state electronic equipment Although designed primarily

as fixed voltage regulators these devices can be used with external

components to obtain adjustable voltages and currents

The LM78XX series is available in an aluminum TO-3 package which

will allow over 10A load current if adequate heat sinking is provided

Current limiting is included to limit the peak output current to a safe value

Safe area protection for the output transistor is provided to limit internal

power dissipation If internal power dissipation becomes too high for the heat

sinking provided the thermal shutdown circuit takes over preventing the IC

from overheating Considerable effort was expanded to make the LM78XX

series of regulators easy to use and mininize the number of external

components.

It is not necessary to bypass the output although this does improve

transient response Input bypassing is needed only if the regulator is located

far from the filter capacitor of the power supply.

For output voltage other than 5V, 12V and 15V the LM117 series provides an

output voltage range from 12V-57V.

Features

Output current in excess of 1A

Internal thermal overload protection

No external components required

Output transistor safe area protection

Internal short circuit current limit

Available in the aluminum TO-3 package

LM 35A

Features :

1. Calibrated directly in Celsius (centigrade)

2. Leniur + 10.0 mv / 0 C scale factor

3. Rated for full - 55 degree to + 150 degree C. range

4. Suitable for remote applications

5. Low cost dut to water-level trimming

6. Operates from 4 to 30 V.

7. Operates from 4 to 30 V

8. Less than 60 micro Amp. current drain

9. Low self-heating, 0.08 degree C. in still air

10. Nonlinearity only 1/4 degree C. typical

11. Low impedance output, 0.1 Ohm for 1mA. load.

Description :

The LM 35 is precision integrated - circuit temperature sensors whose

o/p voltage is linearly proportional to the celcius ( centigrade) temp. The LM

35 thus has an advantage over linear temperature sensors calibrated in

degree kelvin, as the user is not required to subtract a large constant voltage

from its output to obtain convenient centigrade scaling. The LM 35 does not

require any external calibration or trimming to provide typical accuracies as

± 1.4 degree C. at room temperature and ±3/4 degree C. Over a full -55 to +

150 degree C. range. Low cost is assured by trimming and calibration at the

water level. The LM 35s low o/p impedance, linear o/p, and precise inherent

calibration make interfacing to read-out or control circuitry especially easy.

It can be used with single power supplies or with plus and minus supplies,

As it draws only 60 A from its supply, it has very low self heating, less than

0.1 degree C. in still air. The LM is rated to operate over a -55 degree C. to +

150 degree C. temperature range.

The temperature sensor is connected to INO of ADC 0809

Typical Application :

i) Basic centigrade temperature sensor ( +20C. to + 1500C.)

ii) Full-range centigrade temperature sensor, (-55 degree C. to +150

degree C.)

Other sensors for same application.

1) RTD (Registance Temperature Detector) :

i) Platinum (-190 to 660 degree C.)

ii) Nickel ( 0 to 325 degree C.)

100 Ohms platinum sensors is perhaps the most widely used RTD.

2) Thermocouples :

i) Copper - constantan ( -180 to 370 degree C.)

ii) Iron - constantan (0 to 760 degree C.)

iii) Chromel - Alumel (0 to 1260 degree C.)

iv) Platinum - platinum ( 0 to 1480 degree C.)

3) Thermister :

Oxides and Sulphides of Copper, Cobalt, Manganese etc (range from

100 to 300 degree C)

Special thermostats made of aluminium onside covers a high

temperature range from 800 to 1000 degree C

4) AD 590 :

The temperature range for measurement is 0 to 200 degree C

c) For Pressure :

A piezo tranducer can be used as a pressure sensor with the use of a

suitable weight (say upto 100g) it can be used to record pressure in the

ground, which are almost always present for one reason or another. Were we

are interested in signals in the middle frequency range, but our amplifier has

no lower cutoff frequency. By adding a capacitor to the negative feedback

path as shown in above figure. We can provide such a cut off. Now we can

set a desired voltage using a voltage divider. Using a TLC 272 the Cut can

be run from a single 5v power supply.

We have here the making of a sensitive earthquake detector a Normal

piezo transducer can serve as sensors; if we use polarised capacitors. we can

use rather greater weights.

Piezoelectric transducers:

A class of solid polycrystalline dielectic materials when deformed by

the application of force generate electric charge and oice versa. This is

known as piezoelectric effects.

The charge produced due to the deformation by the application of

pressure can be measured by a pair of electrodes mounted suitebly. Natural

crystals like quartz, Rochelle salt and symthetic materials like lithium

sulphate, ammonia dihydrogen phosphate etc. exhibit the piezoelectric

phenomenon.

The piezoelectric transducer is out from a larges crystal in the

direction of any of the electrical or mechanical axis, perpendicular to optical

or crystal axis. The electrical axis is known as X axis and the mechanical

axis as Y axis.

The pressure measurement using a (3) electrical crystal is shown in

fig. below. Let F be the force applied in the direction of Z, resulting in total

charges and voltage e then.

Relay Driver Circuit

Features :

1. Seven Darlingtons per package.

‘ 2. Output current 200mA per driver (600mA peak)

3. Output voltage 50v.

4. Integral supression diodes for inductive loads.

5. Outputs can be paralleled for higher currents.

6. TTL/CMOS/PMOS/DTL compatible inputs.

7. Inputs pinned opposite outputs to simplify layouts.

Description :

The ULN 2003 is high voltage, high current darlingtone arrays

each containing seven open collector darlington pairs with common emitters

each channel is rated at 200mA and can with stand peak current of 600mA.

Suppression diodes are included for inductive load driving and the input are

pinned apposite the outputs to simplify board layout.

Application :

This device is useful for driving a wide range of loads including

solenoids, relays DC motors, LED displays filament lamps, thermal

printheads and high power buffers.

The controlling of three parameters such as water level,

temperature and light intensity. The Relay 1, 2 & 3 are connected to the

ULN 2003 IC at pin No. 16, 15 & 14 at pin No. 1, 2 & 3 connected to the

microcontroller port 2 i.e. P2.0, P2.1, P2.2 Respectively.

Regulated power supply :

A DC power supply, which maintains a constant output voltage

irrespective of AC mains fluctuations or load variation is known as regulated

power supply. A regulated power consists of an ordinary power supply. A

voltage regulator and ripple filtering capacity.

The primary function of any voltage in it’s o/p circuit at a pre-

determined. Value over the expected range of loads circuits. working is

against regulators are variations load current input voltage of temperature.

The degree to which regulator can maintain a constant voltage in the face of

this variations is the basic figure of the ment.

In this project the requirements of power supply is +12v,-12v,

+5v. The transformer of 12-012v is used and as supply is rectified by

rectifier to achieve DC.

RELAY :

Relay is electrically operated switch. it is employed to control

large power but low power is required to operates relay. it can be considered

as remote control switch. When coil and electromagnetic relay is energized

and de-energized, the electrical contents may be ON OFF and change over.

Relays can be hermetically scaled to protect from moisture, dust etc. Relay

are used to close the circuit and to open an electric circuit. The contact are

isolated from coil. Solid state relays are used in industrial application. Solid

state relays are diodes, transistor, Optocouplers etc. Main difference between

switches and relay is that switches are manually operated where as relay is

electrically operated.

Circuit Dia

RA0/AN02

RA1/AN13

RA2/AN2/VREF-/CVREF4

RA4/T0CKI/C1OUT6

RA5/AN4/SS/C2OUT7

RE0/AN5/RD8

RE1/AN6/WR9

RE2/AN7/CS10

OSC1/CLKIN13

OSC2/CLKOUT14

RC1/T1OSI/CCP2 16

RC2/CCP1 17

RC3/SCK/SCL 18

RD0/PSP0 19

RD1/PSP1 20

RB7/PGD 40RB6/PGC 39RB5 38RB4 37RB3/PGM 36RB2 35RB1 34RB0/INT 33

RD7/PSP7 30RD6/PSP6 29RD5/PSP5 28RD4/PSP4 27RD3/PSP3 22RD2/PSP2 21

RC7/RX/DT 26RC6/TX/CK 25RC5/SDO 24RC4/SDI/SDA 23

RA3/AN3/VREF+5

RC0/T1OSO/T1CKI 15

MCLR/Vpp/THV1

U?

PIC16F877A

D7

14D

613

D5

12D

411

D3

10D

29

D1

8D

07

E6

RW5

RS

4

VSS

1

VD

D2

VEE

3

LCD?LM016L

68.0

3

1

VOUT 2

U1

LM35

D1LED-GREEN

1.0 LDR1LDR

R1910K

1B1

2B2

3B3

4B4

5B5

6B6

7B7

8B8

1C 18

2C 17

3C 16

4C 15

5C 14

6C 13

7C 12

8C 11

COM 10U1

ULN2803

RL1NTE-R46-24

RL2NTE-R46-24

RL4NTE-R46-24

+12 V

+12V

+12 V

+12 V

Working of Project

This project is hardware based project. In this project, electric power is saving through

the MICROCONTROLLER and also time saving.

This circuit contains 2 IR Tran receivers, Microcontroller, Relay driver circuit, Relay, 16*2

Model LCD screen, , LDR and temperature sensor.

In this type of circuit, 2 IR sensors are connected to microcontroller which is placed near

the Gate, between these two IR sensor, length us about 20-25 cm. When the person is enter then

IR sensor get effected and IR sensor is get effected when any person get exit. There are three

Relays which they are connected to Microcontroller, throughout Relay driver which is capable to

drive the current of relay. In this circuit Relay 1 is get connected to the main line of power supply.

Relay 2 is connected to the Heater of AC. Relay 3 is connected to the porch/pole lamp. 1 ADC is

connected to the Microcontroller which is given the Analog value of temperature.

We can quickly make the relay on/off using keypad for local operation

To indicate the status of relay, there is a LED indicator.

APPLICATIONS

1] Industrial Level:

Due to this project design, owners will able to save the amount of

electricity they consume.

2] Domestic Level:

This design has direct control over electricity so there is direct link between

the money consumer spends and the value they gets.

Micro-controller operating voltage is only 5V and current driving

capability is not much more so we had connected the driver ckt. i.e

ULN2803, this chip is capable to drive 12V relay but we have used only

three of them and operating voltages of ULN2803 is +12V. In this chip it

have internal 8 darlington pairs. It can be capable to drive 1 Amp. and 12V

DC. and this chip is available easily in market, so we can use this chip.

Micro-controller should have frequency to execute instructions, so

11.0962 MHz crystal is connected to Pin no. 18 and 19 of micro-controller.

also it should be calculating speed of micro-controller. It depends on chip

that can use in circuit.

Whole entire ckt. have power that is taken from step down

transformer 9-0-9 1Amp. because our ckt. is running on first +5V and then

second +12V for relays. So 9-0-9 1Amp step down transformer gives

sufficient voltage in practically 9-0-9 is gives the near about 12 to 13V AC.

It must convert in DC, so we have used two diodes across 9V and 9V,

0 is our ground voltage. it doesn’t gives pure DC voltage. For pure DC

voltage we connected 1000µF 25V in between positive and ground voltage.

Our first aim is that +12V is completed but our microcontroller and other

chip should have +5V so LM7805 regulator is used for +5V’s.

Workings of project is 1st initialized LCD that is when e-bit is 1

command and it is 0, it displays data. All the data for display i.e. for please

wait...... and next. It displayed LDR = ....... and temperature = ........oC and

persons count. When we locate the IR transmitter and receiver on the door

entrance, When 1st interrupt comes so it means any person is entered and

second interrupt is come when person is out, When 1st IR receiver cut and

then 2nd IR cut, it means the counter is increases by one and respective relay

is ON and IInd IR cut first and then Ist IR out then counter is decreases by

One so relay OFF. That relay is connected to power ON or OFF of main

phase.

Other 2 relay corresponds ON or OFF According to the LDR

Resistance and Temp Values which is convert in digital form ADC. When

resistance of LDR is high then porch light is ON, On the condition when any

person is enter otherwise it is OFF Condition. When the temperature is high

3rd Relay is ON Otherwise it is OFF State, In Programming There is define

Value of LDR and temp Values Of UTP and LTP (Upper threshold level and

lower threshold level ) Corresponding Relay ON/OFF. Of that mark Values.

INTELLIGENT LCD DISPLAY :

In this Section, we examine an intelligent LCD display of two lines,

20 Characters per line, that is interfaced to the 8051. The protocol

(handshaking) for the display and the interface to the 8051.

The display contains two internal byte-wide resisters, one for

commands(RS=0) and the second for characters to be displayed (RS=1). It

also contains a user-programmed RAM area (the character RAM) that can be

programmed to generate any desired character that can be formed using a

dot matrix, To distinguish between these two data areas, The hex command

byte 80 will be used to signify that the displayd are a RAM Address 00h is

chosen.

Port one is used to furnish the command or data byte, and ports 3.2 to

3.4 furnished resistor select and read/write levels.

The display text varying amounts of time to accomplish the functions

listed. LCD bit 7 is monitored for a logic high (busy) to ensure the display is

not overwritten. A slightly more complicated LCD display ( 4 lines x 40m

Characters) is currently being used in medical diagnostic system to run a

very similar program.

LCDISP

The program lcdisp sends message “Hello There” to an intelligent

LCD display. Port 1 supplies the data byte. Port 3.2 selects the command(0)

or data (1) registers. Port 3.3 enables a read (0) or write (1) lable, and Port

3.4 generates an active high-enable strobe.

Function :

Clear LCD Memory, home cursor

Clear and home cursor only

Screen action as display character written

S = 1/0 : Shift Screen / cursor

I/O = 1/0 : Cursor R/L, screen L/R

D = 1/0 : Screen on / off

C = 1/0 : Cursor on / off

C = 1/0 : Cursor Blink / No blink

S/C= 1/0 : Screen / Cursor

R/L = 1/0 : Shift one space R/L

DL = 1/0 : 8/4 Bits per characters

N = 1/0 : 2/1 Rows of characters

F = 1/0 : 5x10 / 5x7 Dots / characters

Write to character RAM address after this

Write to Display RAM address after this

BF = 1/0 : Busy / Not busy

Write byte to last RAM Chosen

Read byte from last RAM chosen

PCB DESIGN

INTRODUCTION

Printed circuit board is a piece of art. The performance of an

electronic circuit depends upon the layout and design of PCB. The PCB

design of the circuit operation should be very precise to work it properly.

The soldered point should be small enough so that any stray between these

points should not exist. Also high package density of components can

produce stray which should be avoided by proper circuit designing and

components should be spread in such a way that two-component produce

minimum stray. Also the track of the PCB, soldering points and components

mounting should be very correct and that will be of great help to success the

project.

To make the PCB with professional touch, the general method

that should be carried out is as follows.

LAYOUT PLANNING:

The layout of the PCB has to incorporate all information on the

board, before one can proceed further for the artwork preparation. This

planning procedure depends on many factors.

LAYOUT SCALE:

Depending upon the accuracy required artwork produced

should be at 1:1 or 2:1 scale. Accordingly the size of the artwork will be

equal to four times or sixteen times of that actual PCB. The layout is best

prepared on the same scale as artwork.

LAYOUT SKETCH:

The end produced of the layout design is the pencil sketched

component and conductor driving, which is called layout sketch. It contains

all relevant information for preparation of artwork.

Besides the components outlines, components holes and

interconnection line (patterns) the layout should also include the information

on.

Diameter of component hole, IC transistor pads.

Minimum spacing between the conduction lines that must produced.

Standard conductor widths all should be used for specified

application.

ARTWORK:

Preparation of artwork is considered as first step in preparation

of PCB. Following steps are included while designing the artwork. A

polyester foil and tracing paper may be used. Basic methods of preparing

artwork are:

1. Ink the drawing.

2. Using block tapes and sticking patterns.

3. Using red and blue transparent tapes.

The artwork is then converted to photonegative of proper size.

PHOTOGRAPHIC FILM PRODUCTION:

A film negative of actual PCB is required. The following

equipments are required for photo reduction.

Camera

Lens system with minimum distortion.

Light arrangement at the back of the negative to provide contrast of

1000:1.

From light arrangement with a contrast of 10:1.

The range of reduction of artwork is 2:1 to 4:1. A special darkroom

is required to prepare negative. Room temperature should be less than 25°C,

sufficient circulation of dust free air. The room should be light proof.

PREPARATION OF SINGLE SIDE PCB:

In single side PCB, the conductor tracks run only on one side of

copper cladded board. Thus crossing of conductor is not allowed. Figure

shows the steps to be followed in preparing single sided PCB.

PROCEDURE:

Base material is selected and it is mechanically and chemically

cleaned. Then the photo resists solution, which when exposed to light of

proper wavelength, changes their solubility in the developers, and is

uniformly applied. There are two types of photo resists:

1. Negative acting.

2. Positive acting.

Coating of photo resists is done by:

1. A spray coating.

2. Dip coating.

3. Roller coating.

The coated paper clad laminate and film negative are kept in glass

frame in intimate contact with each other. The assembly is exposed to

ultraviolet light for three minutes. The exposed board is rinsed in the

developer tank. Proper developer has to be used for particular photo resists.

Then the PCB is dyed in a tray, the dye reveals the faults due to contrast,

which are then removed by retouching.

Etching removes the unwanted copper. The spray etching gives

the best results. Cupric chloride is regenerative and is thus preferred to ferric

chloride. The etching solution is kept agitating by circulating low pressure

air at the bottom of the tank through air nozzles. Then the board is drilled

with a high speed drilling machine. Centering of hole on the land pad is

done automatically.

SOLDERING AND SOLDERING TECHNIQUE

There are basically two types of soldering techniques:

Manual soldering with iron.

Mass soldering.

SOLDERING WITH IRON:

The surface to be soldered must be cleaned and fluxed. The soldering

iron is switched on and allowed to attain soldering temperature. The solder

in the form of wire is applied near the component to be soldered and heated

with iron. The surfaces to be soldered are filled, iron is removed and the

joint is cooled without disturbing.

The following precaution should be taken while soldering:

Use always an iron plated copper core for soldering iron.

Clean the component leads and copper pads before soldering.

Apply solder between components leads, PCB pattern and tip of

soldering iron.

Use optimum quantity of solder so that q is small.

Remove flux residues from PCB with solvents like isopropyl alcohol.

Use Sn 60 (Sn 60%, Pb 40%) or Sn 63 (Sn 63%, Pb 37%) composition

solders.

SOLDERING:

Soldering is a process used for jointing metal parts. It is necessary to

use molten metal known as solder.

During soldering, relative positioning of the surfaces to be

joined, wetting of this surface with molten solder and cooling time for

solidification is important.

MASS SOLDERING:

Mass soldering is used where large numbers of joint are to be

soldered simultaneously. It has high productivity, and reliability of final

assemblies.

DIP SOLDERING:

A prefluxed PCB with assembled components is dipped

vertically into clean solder bath to depth. It uses 60% tin and 40% lead. The

board is kept in bath for 2-3 seconds and angled path should be followed

while taking out it.

WAVE SOLDERING:

The assembled board is applied flux. It is preheated while

passing through conveyor belt to 110°C and then to 140°C. It then passes

over a l wave of solder.

Thus the various steps in the mass soldering are as follows.

1. Assembling the board.

2. Flux application.

3. Flux drying or preheating.

4. Soldering.

5. Cooling

6. Flux removal.

DRAWING PREPARATION

With the circuit diagram & component is hand, draw the complete

layout on a plane sheet of tracing paper in the same way as if you are

assembling the circuit keep the lives one side, and line on the other side as

bar as possible. When all the components are mounted on the tracing paper

take a etch pen to mark the connection on the tracing paper. Remove the

components and give finishing touches to the marking so that all

connections are shown with equal width. The layout of the figure is shown

in figure.

PRINTING OF PCB

The drawing so prepared has to imposed over the glass epoxy. Take a

PCB terminated sheet and cut the of required size of PCB by using hacksaw

place the glass epoxy plate sheet on a table, keeping the glass epoxy side on

rub away the dirt, grease and oxide wish a sand paper. Now keep carban

paper of the same size on PCB taking glass epoxy surface on the top carban

paper. Since the tracing paper is transparent you can now reproduce carbon

print over the PCB. After tracing the PCB layout now paint the tracks wish

the help of oil paint and brush, keep plate in open to dry. After the paint on a

copper side has dried, check the drawing carefully, excess paint should be

scratched off wish of a blade.

ETCHING OF PCB

In a tray, take water and mix a few tea spoons of ferric chloride

powder and few drop of HCL. Immerse/dip the PCB in this solution keep the

PCB in this solution for about 40-50 min.

Reaction - 2FeC13+2Cu=2CuC12+Fe2Cl

Observe the changing color of copper surface. Take out the PCB from

the solution only when the unmarked portion of copper is completely

dissolved in this solution wash the PCB wish water. After washing PCB,

remove the paint with a soft piece of cloth or cotton. Now the plate is what

we caII it as printed circuit board.

FLUX

It is used to dissolve & remove the oxide & other contaminators frem

the surface of PCB, & to remove the ability of solder to spread over

evenlynon the surface of PCB. After soldering the coating of flux is mixed is

removed and fabrication is completed.

DRILLING, MOUNTING AND SOLDERING.

After the etching process drilling is done for mounting the compo-

nents. Drill the board by using hand drill or machine drill. Before inserting

the leads of the components are placed on the irrespective position

(according to the circuit Diagram) this process is called as component

mounting.

Now the next process is soldering. In this process, the leads of compo-

nents are joined/ soldered with the copper tracks of PCB. For this tussible

alloy metal which is known as 'SOLDERING WIRE1 is required soft solder

has 37% of lead and 63 % of zinc and is used because of its excellent drying

action. Its melting point is very low. It gives mechanically strong point for

soldering the components, soldering gun is used. Flux is used as an

inorganic solvent.

Design check list :

General :

1. Has the CKT been analysed and divided into basic area for smooth

signal flow.

2 Is the board size optimum.

3 Are prepared conductors widths and spacing used.

4 Is the jumper used kept to a minimum.

Electrical :

1 Has conductance, resistance, capacitance and inductance effects been

analyzed and especially critical voltage drops and ground.

2 Are conductor and hardware spacing and shape complitible with

insulation requirment.

3 Are polrization adequatly identifies.

Physical :

1 Are terminals and control location compatible with total assembly.

2 Are hot components properly heat sinked cooled or isolated from

board and other heat sensitive components.

3 Are components organized and oriented for case of assembly and

inspection.

Mechanical Design Consideration :

Although printed circuit board load mechanical support to the

component should not be used as a structural member of over all equipment.

Support should be provided at peripheral internals of at least 10mm at the

board edge.

As a good practice boards between 0.636mm and 1.27mm thick

should be supported at intervals of at least 4 inch. This practice increases the

rigidity of board.

Board size shape :

Maximum Size :

The final choice of printed circuit board size and shape will probably

be a compromise. To determine maximum size at printed board Artwork

generation size, accuracy of etching . size of cleaning tank must be

considered.

Thickness :

Printed boards thickness can varied from 0.220 to 0.25 inch but rigid

boards predominantly have thickness of 1.283mm.

Conductor shapes :

Sharp corner and acute bend in conductors should be avoided on both

the conductor itself and adhesive bond and also because of electrical

problems arising from field intensification.

Rounded corners will not only minimize conductor checking. foil

lifting electrical breakdown but also facilitate solder distribution.

Conductor width and thickness :

Width of any conductor is a function of current carried and maximum

allowable heatrise due to resistance.

Conductor Spacing :

Minimum conductor to prevent voltage breakdown of flashover

between adjacent conductors.

The spacing depends upon several factor.

1 Peak voltage difference between adjacent conductors.

2 Atmospherical pressure.

3 Use of coating.

4 Capacitate coupling parameter.

Introducer :

It includes perspective of total systems hardware, including not only

printing writing but each and every component in its final ascertain some

major consideration will be.

1 Product specification.

2 Product specification.

3 Life expectancy.

4 Electronic circuit gain.

5 Impedance, voltage etc.

6 Material and component sources, performance data availability cost,

verification, screening specific relevant design data.

ADVANTAGES

1) Utilities benefits because it saves the electricity.

2) Easy to install and operate.

3) Comparatively affordable

4) Customer need not to pay his attention directly over consumption.

4) This design has direct control over his budget.

APPLICATIONS

1] Industrial Level:

Due to this project design, owners will able to save the amount of

electricity they consume.

2] Domestic Level:

This design has direct control over electricity so there is direct link

between the money consumer spends and the value they gets.

CONCLUSION

As per the system mentioned earlier the project for automatic power

saving using microcontroller, Light controller, Temp controller using

hardware is carried out. It is observed that the system is duly important in

home application & office for measuring & controlling the various

parameters to save the electricity.

As our system consist of hardware. The hardware which has been

used is totally reduced as per the size and complexity by using standard

component. This system automatically controls the light intensity & temp. of

the Room.

Implementation of the system is easier & safer . It found to be reliable

cost and time effective method of measuring & controlling the parameters.

BIBLIOGRAPHY

Books:

1. Op-Amp Linear integrated circuits. (Prentice-Hall of india, 3rd

Edition) - Ramakant Gayakwad. 

2. Process control and instrument Technology (Prentice-Hall of india, 4th

Edition) - Curtis Jonson

3. Computer Based Industrial Control (Prentice-Hall of India, 5th edition)

- Krishna Kant.

4. The 8051 Microcontroller (Penram International publishing, 2nd

Edition) - Kenneth J. Ayala, B.RAM.

5. Hand book of visual Basic (Penram International publishing,Special

Edition) - Gray Cornell

6. Electrical & Electronic Measurement & Instrumentation

- A.K. Sawhney

7. Practical SCADA for industry (Elsevier Publication)

- David Bailey

8. Principles for industrial instrumentation (Tata Mc-Graw Hill

Publication) - Patranabis

Websites:

i) www.nrdcindia.com - Microprocessor based single-phase card

operated energy meter.

ii) www.innovatec.com – Innovatec network prepaid electric

metering.

iii) www.sames.com – Electric energy measurement, measurement

IC SA 9602H

iv) www.atmel.com – Atmel microcontrollers, IC 89C51.

v) www.fairchildsemiconductor.com – Memories, EEPROM, NM

9346.

vi) www.analogdevices.com – Benefits of electronic energy

metering.