24LME201–Engineering Practices Laboratory (GROUP B),

DGCT

WIRING DIAGRAM

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Ex.No:1 RESIDENTIAL HOUSE WIRING

Date:

AIM:
To construct the residential house wiring using switches, fuse, indicator, lamp and energy meter.

MATERIALS REQUIRED:

S. No COMPONENTS QUANTITY
1. Bulb holder 1 no
z2. Bulb 1ns
3. Single way switch(5Amps) 3 no
4. Switchbox 1 no
5. Connecting wires As required
6. Main switch 1 no
7. Energy meter 1 no
8. Indicator 1 no

PROCEDURE:

1. Mark the location of electrical it meson the given wooden board.

2. Mark lines for wiring on the wooden board.
3. The required length of PVC pipe can be fixed along the line with the help of clips.
4. ThewiresofrequiredlengthandcolourwerechosenandthewiringisbeingmadethroughPVCpipe.
5. The bulb holder and switches are fixed in the corresponding location.
6. Use the red holder colour wire for phase line to the bulb through two way switch.
7. The point of the bulb is connected to the neutral line.
8. The red and black wire terminals are connected to main switch.
9. Check the lamp, indicator and plug point.

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RESULT:

Thus the wiring for house was prepared and tested.

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FLUORESCENT LAMP WIRING

WIRING DIAGRAM

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Ex.No:2
Date: FLUORESCENT LAMP WIRING

AIM:
To make and check the fluorescent lamp wiring.

MATERIALS REQUIRED:

S. No COMPONENTS QUANTITY
1. Fluorescent Lamp Fixture 1No
2. Fluorescent Lamp 1No
3. Choke 1No
4. Starter 1No
5. Wires As Per Requirements

THEORY:
Tube light has filament on either side. They are coated with tungsten material. The
inside of the tube has phosphorous coating which is used to convert ultraviolet into visible
light and to give the required color sensation. A choke is used to give transient high voltage
so as to initiate the electron movement which is an iron starter capacitor is used to suppress
radio interference with the switch closed. The current flows through the choke and the starter.
The glow switch suddenly breaks thereby creating the circuit. Due to high conductivity,
inductive property of the choke, a transient high voltage is available across the filament.
Hence the electrons are emitted and travel through the tube. Then tube light is produced.

PROCEDURE

1. Give the connections as per the circuit diagram as shown in figure.

2. Fix the tube holder and the choke in the tube.

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3. The phase wire is connected to the choke and neutral directly to the tube
4. Connect the starter in series with the tube.

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RESULT:

Thus the checking and assembling the accessories of a fluorescent lamp is done.

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WIRING CONNECTION DIAGRAM

N 60WattsLamp

1,

230V

FUSE

P 10A

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Ex.No:3
Date: STAIRCASEWIRING

AIM:
To control the status of the given lamp by using two ways switches.
MATERIALS REQUIRED:

S. No COMPONENTS TYPE QUANTITY

1. Incandescent Lamp 100W 1No
2. Lamp Holder Pendent Type 1No
3. SPDT Switch 230V,5A 1No
4. Wires 1/18‖ 1No
5. P. V. C Pipe 1/4" As Per Requirements

PROCEDURE:
1. Place the accessories on the wiring board as per the circuit diagram.
2. Place the P.V.C pipe and insert two wires in to the P.V.C pipe.
3. Take one wire connect one end to the phase side and other end to the middle point of
SPDT switch 1
4. Upper point of SPDT switch 1 is connected to the lower point of SPDT switch 2.
5. LowerpointofSPDT1isconnectedtothe upperpointSPDTswitch2.
6. AnotherwiretakenthroughaP.V.CpipeandmiddlepointofSPDTswitch2
isconnectedtooneendofthe lamp holder.
7. Another end of lamp holder is connected to neutral line.
8. Screw the accessories on the board and switch on the supply.
9. Circuit is tested for all possible combination of switch position.

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SWITCH POSITION TABLE:

Position of the switch(s1) Position of the switch(s2) Condition of lamp(L)

ON ON
ON OFF
OFF ON
OFF OFF

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RESULT:

Thus the staircase wiring for the bulb was prepared and tested.

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CIRCUIT DIAGRAM:

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MEASUREMENT OF ENERGY USING SINGLE PHASE ENERGY METER

Ex.no:4

Date:

AIM:

To measure the energy using single phase energy meter at UPF load conditioN

APPARATUS REQUIRED:
S.No Name of the Equipment Range Type Quantity
1. Voltmeter (0– 300)V M.I 1

2. Ammeter (0– 5)A M.I. 1

3 Wattmeter 300V,5A UPF 2

4 1ΦVariable resistive load kW 1

5 Connecting wires

6 Stop clock 1
7 Single phase energy meter 240V,5A 1

PRECAUTIONS:

 There should be no load at the time of starting.

 The connections must be made proper for UPF.
PROCEDURE:

 The connections are made as per the circuit diagram.

 The DPST switch is closed and the supply is affected and load is adjusted to full
load value.
 The time taken for10revolutions of the aluminium disc in the energy meter is noted.
 The error is calculated if it is more than +3% the brake magnet is adjusted such that
the error is within +3%.
 The load is reduced insteps and for each step, step #.3 are repeated and the %error
is calculated.

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TABULATION

S.NO Current Timefor10r Wattmeter Power Energy

I(A) evolutions Reading(Wat from
consumed
ts) Energy
meter( =
Observed Indicated KW)
In In
Power *
Sec hour
Time(KWHr)

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RESULT:

Thus the energy is measured using single phase energy meter is measured.

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ELECTRICAL IRON BOX

Ex.no:5
Date :

AIM:-

To find the fault of iron box (ordinary and automatic) and study about them and prepare the
maintenance chart of the possible faults and their remedies

MATERIALS REQUIRED:-
Iron box, Test lamp, Wires

TOOLS REQUIRED:-
Tester, Pliers, Wire Stripper, etc.,

THEORY:-
ELECTRICIRONBOX
An electric iron box is used to iron the cloths.Electric ironbox can be classified into two types as
below

 Ordinary Electric Iron Box

 Automatic Electric Iron Box

ORDINARY ELECTRIC IRON BOX

It consists of Chromium plated base plate, Heating element, Pressure plate and Iron case with
Handle

Sole Plate
It is made up of Cast iron and its bolts are Nickel plated with very shining like glasses.

The heating strip tube wire or Heating Element :

Is a heating element made of ni-chrome wire to turn electrical energy into heatenergy?

The thermostat :

It is made up of flat Nichol wire and wound on a Mica sheet. Its wattagevaries450,
500,1000etc.,Regulate temperature and cut off itself when current flows to the
heating element if too hot.

Pressure Plate
It is made up of Cast iron. Its shape as heating element. It sets and presses
theheatingelementonsoleplatewiththehelpoftwomachinescrewsandnuts.

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Iron Case

It is used for covering the all above parts. In which an insulator terminal and
handle is provided. It is making up of iron sheet with Nickel plating.

Wooden or Ebonite Handle

It is used for holding the bar terminal with stand washers.

Porcelain Sheet
Nut, Bolt and Washers are used to tighten the weight plate and iron case should be insulated
by insulating materials like Porcelain sheet, Mica sheet, Ebonite sheet

AUTOMATIC ELECTRIC IRON BOX

In addition to the above mentioned iron box, the automatic iron box has a
there most at which is connected in series with the element. This most at
controls the temperature. Prevent over heating of iron and thus avoids
damage to the heating element. The required temperature can be obtained
with the help of thermostat.

Principle of Operation

An electric iron box works on the principle that when an AC current passed
through a resistive wire the electrical energy is transferred to heat energy.
The Nichrome wire is heated up to a certain temperature and gets a bright
orange-red color. The wire used in heating element generally made by
Nichrome wire which is a combination of 15% Chromium20% Iron and
remains Nickel.

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Testing
1.By connecting the two ends of connecting lampleads to the terminals of iron box
 If lamp glows dimly it means that element is in working order
 If the lamp does not glow it means that the breaking in the heating element
 If the lamp glows brightly the both sides of the element touch
inthe sole plate

 If the lamp does not glow it means that the breaking in the heating element
 If the lamp glows brightly the both sides of the element touch in
the sole plate
2.The earth testing by connecting one lead to one terminal of electric iron and other lead to
metal parts of the element if the lamp give full light or dim light, there is a leakage in the
iron. If the lamp does not glow, the iron is good

The thermostat

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POSSIBLE FAULTS AND REMEDIES:-

DEFECT CAUSES REMEDIS

1.The iron box does not get Power failure Check the supply
started Loose connection Check the
Break on heating element connection Replace the
heating element

2.Touching gives hock Live part is touching on body Insulate live part

3.Slow heating Lack of rated voltage Improve the voltage

4.In an automatic iron box The thermostat is not Replace the thermostat
power does not break working By new one
Which maintaining the
Required temperature

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RESULT:-

Studied the methods to find out the fault of a ordinary and automatic iron box
and prepared the maintenance chart.

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FAN REGULATOR

Ex.No: 6

Date:

AIM

 Study of Fan Regulator

Fan Regulators four types:

Currently Fan Regulators are of these four types:

Resistive regulator

Phase angle controlled regulator

Inductive regulator

Capacitive regulator (latest).

This is the most common type in household ceiling fans.

How does a Fan Work?

A ceiling fan has a single-phase electric motor and metallic blades connected to it.

Single-phase when given to a motor, unable to provide torque to rotate it. Therefore, a start

capacitor is provided across one of the two windings. which goes out of circuit once the motor

starts. After the start, a run capacitor is there in the service which improves the power factor

and keeps the motor running at its rated speed. In order to regulate the fan speed, a regulator

is provided which varies the voltage across the winding and thus controls the speed. Lower

the voltage lower the speed of the fan. So a regulator controls the voltage levels for the fan.

Direction

The direction that a fan spins should change based on whether the room needs to be

heated or cooled. Unlike air conditioners, fans only move air—they do not directly change its

temperature. Therefore, ceiling fans that have a mechanism for reversing the direction in

which the blades push air (most commonly an electrical switch on the unit's switch housing,

motor housing, or lower canopy) can help in both heating and cooling.

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For cooling, the fan's direction of rotation should usually be set so that air is blown

downward (Usually counter-clockwise from beneath, but dependent upon manufacturer). The

blades should lead with the upturned edge as they spin. The breeze created by a ceiling fan

creates a wind chill effect, speeding the evaporation of perspiration on human skin, which

makes the body's natural cooling mechanism much more efficient.

As a result of this phenomenon, the air conditioning thermostat can be set a few

degrees higher than normal when a fan is in operation, greatly reducing power consumption.

Since the fan works directly on the body, rather than by changing the temperature of the air, it

is recommended to switch all ceiling fans off when a room is unoccupied, to further reduce

power consumption. In some cases, like when fan is near walls like in a hallway, updraft may

cause better airflow. Also another example how updraft can cause better cooling is that fan is

in middle of a bedroom with a loft bed near a wall, meaning breeze can be felt better when

airflow is coming from the top.

Blade shape

Residential ceiling fans, which are almost always reversible, typically use flat,

paddle-like blades, which are equally effective in downdraft and updraft. Industrial ceiling

fans typically are not reversible and operate only in downdraft, and therefore are able to make

effective use of blades that are contoured to have a downdraft bias.

More recently, however, residential ceiling fan designers have been making

increasing use of contoured blades in an effort to boost ceiling fan efficiency. This contour,

while serving to effectively boost the fan's performance while operating in downdraft, can

hinder performance when operating in updraft.

Air conditioning

The most commonplace use of ceiling fans today is in conjunction with an air

conditioning unit. Without an operating ceiling fan, air conditioning units typically have both

the tasks of cooling the air inside the room and circulating it. Provided the ceiling fan is

properly sized for the room in which it is operating, its efficiency of moving air far exceeds

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that of an air conditioning unit, therefore, for peak efficiency, the air conditioner

should be setto a low fan setting and the ceiling fan should be used to circulate the air.

Ceiling Fan Doesn’t Work At All:

Be sure to turn off the fan’s circuit breaker before disassembling the fan or its

switch

These are instructions for troubleshooting a fan that is completely dead. In

other words, it doesn‘t hum or try unsuccessfully to spin. You flip the switch, and

nothing happens.

When a ceiling fan doesn‘t work at all, the first thing to do is to make sure it is

receiving electrical power from its switch and from your home‘s circuit breaker or

fuse box. If that doesn’t work, move on to test whether or not the switch that

controls the fan is defective:

The switch is essentially a gate that opens and closes to interrupt or complete

the black (―hot‖) wires‘ circuit. So the idea is to complete the circuit without the

switch to see if it works. You do this by removing the switch, twisting together the

bare ends of the black wires, and screwing-on a wire nut to secure them. If the fan

works when you do this, the problem is the switch, which you simply replace.

Result:

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EMERGENCY LAMP WIRING

Ex.No: 7

Date :

AIM

To the Study of emergency lamp wiring.

Necessity Emergency light

Emergency lighting is used in an urgent situation like when the main supply is
disconnected or regular electrical light fails. So the sudden electricity loss could result
in a fire otherwise a power cut. This lighting system is used in buildings and it includes
a battery to activate the light automatically once the power failure occurs. In the
emergency situation, these lights play a key role to provide safety for residents. If the
power failure occurs, an emergency light can activate with the help of batteries to
visually show the route safely for residents to leave from the building. This article
discusses an overview of emergency light and its working.

What is an Emergency Light & How it Works?

Definition: An emergency light is used to automatically turn ON a lamp which is

operated by a battery. It stops the user from being into a difficult situation because of
unexpected darkness and helps the user to get access to make an instantaneous
emergency light. This circuit uses light-emitting diodes in its place of the
incandescent lamps; therefore making the circuit is very power efficient as well as
brighter with its light o/p. In addition, the circuit uses an innovative theory to enhance
the economical characteristic of the unit.

Emergency lights are connected to the electrical supply of the building. Each light has
its own circuit. These lights include a battery so that it works like a backup power
supply once the building loses its power supply. Here, the lifespan of a battery is short
when we compare it with other kinds of lighting systems. So all the emergency lights
must be checked to make sure the battery can give emergency light for a minimum of

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90 minutes. These tests are necessary to check the performance of the battery every six
months with professionals.

How do Emergency Lights Appear?

There are different kinds of lights available in the market in different sizes and
shapes. Each light is designed based on the application. There are some common
emergency lighting systems used in buildings are

 Exit Lights
 Batten Lights
 Oyster Lights
 Spot fire Lights
How to Make an Emergency Light / DIY Emergency Light

The DIY emergency light can be designed in a step by step process like the following.
The required components of the 12v emergency light circuit diagram mainly
include LDR, 50K VR, 10K Resistor, BD139 & BD140 transistor, 33ohm resistor, and
white LED and 12V battery.

Connect the circuit on the breadboard as per the diagram shown below using the above
components.
In this circuit, the LDR based light will activate a high watt white LED once there is
dark in the room. It can be used as a simple lamp in the children‘s room to keep away
from the panic condition once the power gets fail. This circuit gives sufficient light in
the room.

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Emergency Light Circuit using 12v Battery

The design of this circuit is very easy so that it can be arranged in a little box. As a
power source, a 12 V small battery is used to provide the supply to the circuit. The
transistors like T1 & T2 are used as electronic switches for switching ON/OFF the
white LEDs.

When there is enough light within the room, then LDR activates so that the base
terminal of the T1 transistor will become high. The remaining transistor-like T2 also
Turns off as its base terminal is grounded. In this condition, the white LED will turn off.
Once the light dropping over the LDR decreases, then the T1 transistor in forwarding
bias will provide base current to transistor ‗T2‘. This ‗T2‘ transistor will turn on to
make the white LED ON.

Here, the LED is 1 watt high bright Led diode. It uses approximately 300 am current.
So it is better to turn off the lamp to save the power in a battery after a few minutes

Emergency Light Circuit Diagram

An emergency light system is used to turn ON a lamp automatically where a regular

AC supply stops working and turns OFF once the main power supply gets back.

This light is essential where the power cut occurs frequently, so it can avoid the user
from a difficult situation while going through when unexpectedly mains power supply
turns off. It permits the user to access an alternative like turn ON an inverter or a
generator until the main supply is restored.

Circuit Explanation & Working

Here there are two circuits that work on using a 6V battery and 12v battery. The
construction of these circuits is shown below. These circuits can be built with LEDs in
place of incandescent lamp, therefore this is extremely power efficient & clear with its
output.

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6V Emergency Light Circuit Diagram

The circuit diagram of 6V emergency light is shown below. The required components
of this circuit mainly include resistors 10K & 470 ohms, capacitor (C1) -100uF/25V,
Bridge diodes like D1, D2 (1N4007), D3 to D5 (1N5408), T1 (BD140), Tr1( 0 to 6V &
500mA), LEDs and S1 switch including change over contacts with the help of a 6V
battery.

Emergency Light Circuit using 6v Battery

In the above circuit, a standard power supply mainly includes the transformer, a
capacitor, and a bridge circuit. The essential component used in this circuit is a PNP
transistor. Here, this transistor is used as a switch.

Once the main supply is ON, then the positive supply gets the base terminal of the
‗T1‘transistor, so it will be switched off. Thus the voltage from the battery is not able to
reach the LED bank, keeping it switched off. In the meantime, the battery is charged by
the power supply voltage and it‘s charged through the system of trickle charging.

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However, as soon as the main supply interrupts, then the +vet at the base terminal of
the transistor will disappear & it will be in forwarding bias through the resistor-10K.If
the transistor ‗T1‘turns ON, immediately the LEDs will blink. At first, all the diodes
are connected in the voltage lane and are slowly go around one by one when the LED
gets dimmer.

Applications of Emergency Light

The applications of these lights include the following.

 Emergency lights are used where the light turns on automatically when the power
supply gets off.
 These are used as emergency lamps in buildings, homes, workplaces, study rooms in
order to keep away from unexpected power failures.
 These lights are used in several industries

RESULT:-

Studied the methods to find out the fault of an emergency lamp

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CIRCUIT DIAGRAM:

LOW PASS FILTER:

SOLDERING KIT:

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EX NO: 1 & 2 SOLDERING ELECTRONIC COMPOMENTS
DATE: I) ON PCB AND ii) CHECKING CONTINUITY.

AIM:

To assemble and Solder the electronic components on a printed circuit board

And checking the continuity for the given circuit.

APPARATUS REQUIRED:

S.NO APPARATUS QUANTITY

1 1
Soldering rod, Soldering lead.
2 1
Flux.
3 As Required
Resistor.
4 As Required
Capacitor.
5 1
Signal generator

THEORY:

i) SOLDERING ELECTRONIC COMPOMENTS ON PCB

Printed circuit board is the base plate over which all components are mounted and
soldered. The inter connection between the components made by in metallic tracks..

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PROCEDURE:

1. Prepare Your Iron

 Before you use an iron to solder, you need to complete a process known tinning. This
process is all about coating the tip of the iron in solder to aid in the heat transfer process.

 Begin this process by warming up the iron thoroughly and letting it rest until it reaches its
full heat. Once it has completely heated, coat the tip thoroughly with solder, making sure
to cover the entire tip. You’ll need to use plenty of solder to do so, and some of this will
likely drip. Be prepared for this.

 Once you’re certain the entire tip is coated, wipe it off with a wet sponge to get rid of any
excess flux residue. Do this right away, or else the flux may have time to solidify on the
tip and become difficult to remove later.

2. Prepare Your Surface

 The key to a good soldering job is to start with a clean surface. To ensure your PCB
board is clean and ready for soldering, use an industrial cleaning pad to wipe the surface
clear of any dust and debris. You may also use an acetone cleaner to give it an additional
wipe down. Finally, you might try giving it a few blasts of compressed air, as these will
remove any small particles stuck in the board.

3. Place the Components

 Unless you’re working with an exceptionally simple circuit board, you’ll likely only be
soldering one or two components at once, as opposed to doing the entire board in one
session. We recommend starting with the smaller pieces and working up to the larger
ones. This helps keep the board flat and balanced as the process begins, rather than
weighing it down on one side with a single heavy piece.

 Begin by selecting a few small components and placing them where they belong on the
board. Bend the leads as you find you need to and insert the component into the holes
where they belong. If you’re having trouble getting the piece to stay still once you aren’t
holding it in place, try bending the leads so that they rest at a 45-degree angle along the
bottom of the board.

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4. Apply Some Heat

 Add a very small amount of solder to the tip of the iron. This isn’t the solder that’s going
to hold the components in place but is rather intended to conduct heat from the iron to
the board.

 To properly heat the joint, hold the iron so the tip touches both the board and the
component lead. This positioning is critical since if the tip is in contact with only one of
these pieces, the solder won’t stick. Once the tip is in position, the solder you applied
earlier will make contact with both the lead and the board, heating them up and preparing
them for the soldering. Hold the iron in position for a few moments before removing it.

 It’s possible to overheat during this stage, which you’ll want to avoid. If you notice the
area starting to bubble, remove the heat immediately. Wait for it to cool and then heat it
again, more cautiously this time.

5. Add Solder to the Joint

 Once you’ve heated the joint, you’re ready to solder. Begin by touching the tip of a strand
of solder to the solder pad and lead. If you’ve heated this space correctly, the solder
should flow freely and the flux should begin to liquefy and bubble. Keep adding solder
around this joint until it’s entirely coated, forming a small mound. When you’ve reached
this point, stop adding solder and remove your iron from the area, setting it aside.

 As the joint cools, make sure it stays absolutely still. If you jostle it or allow it to move,
the finish will look dull and grainy.

6. Finish Up

 Once the joint has finished cooling, conduct a small inspection of it. If the solder joint
looks good, move on to trimming the lead. You’ll do this by using side cutters to cut at
the very top of the joint. From here, move on to the next component you want to solder in
place. Once you’re finished with all your soldering for your current session, make sure to
clean up any extra flux from the board, leaving you with a clean and finished product.

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ii) CHECKING CONTINUITY:

THEORY:

The continuity of a wire conductor without a break has practically zero ohms of
resistance. Therefore, an ohmmeter may be used to test continuity. To test continuity, select the
lowest ohm range. A wire may have an internal break, which is not visible due to insulation, or
the wire may have a bad connection at the terminals. Checking for zero ohms between any two
points tests the continuity.

PROCEDURE:

For soldering a Low Pass Filter circuit consisting of a resistor and capacitor andchecking the
continuity.

 The terminal of the resistor and capacitor are thoroughly cleaned.

 The joint to be made is tinned says the joint.
 A soldering gun is heated using power supply till it attains the required
temperature.
 Using the heated soldering gun, the tinned joint is soldered.
 A small AC signal nearby or equal to 5V is applied between the terminals A &B.
 Using the Multimeter the continuity of the circuit is checking.

Precaution:

The terminal of the components should be thoroughly cleaned also soldering care should
be taken while selecting the proper size of soldering HD.

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RESULT:

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EX NO: 3 STUDY THE ELEMENTS OF SMART PHONE

DATE:

AIM:

To study the elements of Smart Phone.

THEORY:

Functional Blocks of a Typical Smart phones:

 At the core is the processor sub-system that coordinates everything in thephone as well
as runs the User Interface and applications. The RF sub-system contains the RF front-end,
antennas and modem, and is the section responsible for all wireless functionalities.
 The display sub-system is what the user initially notices about the Smartphone since it is such
a visibly large part of the entire device. The peripheral sub- system is what users would
consider to be features of the phone. It includes such things as cameras, fingerprint scanner,
audio, GPS, accelerometer and other similar components.
 Finally, there is the battery and power management sub-system. It is, of course, responsible
for storing and then providing power to the entire phone. Runtime is one of the key aspects a
typical user considers when buying a Smartphone.
 In an actual Smartphone, in order to cram all these sub-systems into the available space,
many portions of these sub-systems are actually implemented on a single main board. This
includes most everything except the actual display, the antennas, the peripherals, and the
battery.

Processor

 At the heart of the Smartphone hardware is the system processor. In modern Smartphone, this
is mainly based on a System on a Chip, or SoC, that integratesmore than just the processor.

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 This SoC is by far the most complex component in the entire Smartphone since it
encompasses as much as possible in order to save space. This SoC and what it actually does,
differ from one Smartphone to another.
 Here is a look at one of them: the Qualcomm Snapdragon 855. It is used in a variety of
Smartphone, including the Samsung Galaxy S10/S10+.
 Additional components that are part of the processor sub-system consist of external memory,
both volatile and flash. These, together with the processor SoC, are on the same motherboard,
usually under a metal can that is used as anEMI (Electromagnetic Interference) shield.

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Display

 A Smartphone display is usually sourced as a complete sub-assembly that is then

incorporated in the product. That’s mainly because these are complex products that require
large investments to design and manufacture. So, only a very limited number of companies
such as Samsung, LG Display and a few others make the kind of displays currently used
in Smartphone.
 The type of display found in modern phones is the Active Matrix Organic LED, or
AMOLED. Not to be confused with LCD’s with OLED backlights, AMOLED displays offer
very high contrast ratios, high dynamic range, fast refresh rates and wide viewing angles, all
in a very thin, and even flexible display.
 In addition to the actual display element, the whole assembly also contains drivers and
interface electronics such as MIPI. The touch screen interface is also built-in. This, in turn,
offloads the low-level task of actually displaying an image from the processor’s GPU
(Graphical Processing Unit).

RF Section

 There are many different cellular communication standards, and smart phones have to
support the latest standards. Additionally, a Smartphone must be able to support previous
generations of cellular standards.
 This makes for a very large combination of modulation schemes. For example, even the latest
Smartphone still support the very early GSM/EDGE and CDMA standards. This is
accomplished by a multi-standard modem that, in modern phones, is part of the processor
SoC.
 There is, however, more to the implementation of cellular communication than just the
modem. For one thing, different countries have different frequency bands for cellular
communications. Universal, or quad-band, phones can communicate on any one of these four
current cellular bands: 850MHz, 900MHz,1800MHz, 1900MHz
 This is accomplished by having the modem implement the basebandcommunication protocol,
and then up converting this baseband modulated signal to one of the four worldwide cellular
bands.

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 So, part of the RF sub-system consists of diplexers, duplexers and RF switches that allow the
RF antenna to be tuned to the required band, and also be able to transmit and receive signals
at the same time.
 Finally, an important function of the RF sub-system is to have an accurate Receive Signal
Strength Indicator, or RSSI. Not only are some modulation schemes dependent on the
strength of the received signal, but the RSSI is also used to tailor the transmit power.
 For instance, there is no point wasting battery power transmitting at full power if the user is
very close to a cellular tower.
 In modern phones, the RF sub-system components, except for the antennas, are also on the
motherboard under their own EMI shielding cans.

Fig: Several Parts Present in Smart Phone

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Power Management System

 The Smartphone runs off battery power. This battery must power the entire Smartphone. It
also has to be charged, so a charging system has to be included in the device.
 The many sub-systems in a Smartphone require multiple supply voltages. Operating at the
lowest voltage an active component can reliably operate at, saves power.
 The battery voltage is not constant, and will drop depending on how discharged the battery
is. All of this means that multiple voltage regulators are required to supply these various
supply rails.
 Most of these are switching regulators with high energy conversion efficiencies. However,
some need to be linear regulators in cases where power supply ripplescannot be tolerated.
 This is especially required in the receive sections of the RF sub-system where the received
input signal level can be very low if the phone is far from the nearest cellular tower, or is
indoors. All of these functions are provided by the power management sub-system.
 All smart phones use li-ion batteries. These need special charging methods and they also
need to be protected against electrical abuse, such as over-charging and short circuits.
 These are also achieved by the power management sub-system. It manages the externally
provided power, whether through a physical charging port such as USB or a wireless
charging coil, and safely charges the battery.
 Then, there is the battery itself. It is the largest component of the entire electrical sub-system,
and is usually custom-designed to fit in the allocated volume of the device.

Peripherals

 Some peripherals such as accelerometers are usually found on the main board itself, most are
located off board. These external peripherals are typically sourced as independent modules
that are all connected to the main board by flex PCBs with low-profile connectors.

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 They include front and back cameras, speakers, microphone, fingerprint scanner, haptic
devices, and a variety of sockets and adapters for removable items such as SIM card, SD card
and earphones.

Sensors

 There are five primary sensors in a Smartphone that allow it to give you the functionality of a
‘touch-enabled smart device.’ The names of all these sensors and their importance have been
detailed below:
 Accelerometer: Used by apps to detect the orientation of the device and its movements, as
well as allow features like shaking the phone to change music.
 Gyroscope: Works with the Accelerometer to detect the rotation of your phone, for features
like tilting phone to play racing games or to watch a movie.
 Digital Compass: Helps the phone to find the North direction, for map/navigationpurposes.
 Ambient Light Sensor: This sensor is automatically able to set the screen brightness based on
the surrounding light, and helps conserve battery life. This would also explain why your
Smartphone’s brightness is reduced in low-light environments, so it helps to reduce the strain
on your eyes.
 Proximity Sensor: During a call, if the device is brought near your ears, it automatically locks
the screen to prevent unwanted touch commands.

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RESULT:

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EX NO: 4 ASSEMBLY AND DISMANTLE OF LED TV

DATE:

AIM:

To study the assemble and dismantle process of LED TV.

BLOCK DIAGRAM OF LED TV:

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DISMANTLE OF LED TV

PROCEDURE:

STEP 1: To begin, lay the TV screen-down on a smooth surface.

STEP 2: To begin removing the back plate, find and remove all screws indicatedwith the
screwdriver.

Once all of the screws are removed, carefully pop off the back plate withoutdamaging any of the
connected wires.

STEP 3: Slide the power cord free from its metal framework.

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After the power cord has been moved, remove the four screws keeping the housingin place. Once
finished, remove the housing as well.

STEP 4: Remove the three silver screws connecting the circuit board to the rest ofthe TV that
are circled in the picture using the screwdriver.

Remove the final silver screw, making sure to avoid disconnecting any of the wiresthat obscure it
from view.

STEP 5: Once the screws are all removed, slide the flat-head screwdriver into the small gap
between the front and back plates. Use the screwdriver to pry the platesapart and lift the back
plate up.

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STEP 6: Completely separate the back from the front and flip the back section overso that the
screen is now on top.

STEP 7: Find the cable pictured and detach the plastic film protecting the circuitryto which the
cable is attached.

After detaching the plastic, detach the wire connecting the screen to the rest of theTV.

STEP 8: Next, the circuitry needs to be removed from the TV itself. Lift the screen circuitry
free from the adhesive and then lift the screen free from the back sectionof the TV.

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ASSEMBLING OF LED TV

PROCEDURE:

Step1: Place all the circuits on those respective places.

Step 2: Connect all the interfacing cables.

Step 3: Tighten the screw of that circuits in the panel.

Step 4: close the lid & replace all the screw on the respective holes.

Step 5: Connect the power cable & do the finishing UP process.

Assembling is literally the reverse process of Dismantle. Hence, remember thoseprocesses to repeat
the same.

RESULT:

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EX NO: ASSEMBLY AND DISMANTLE OF COMPUTER

5(a)

DATE:

AIM:

To study the assemble and dismantle process of Computer

PARTS OF COMPUTER SYSTEM:

The computer system is made up of following external devices:

 CPU cabinet
 Monitor
 Keyboard
 Mouse
 Printer/scanner (if attached)

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PROCEDURE:

DISASSEMBLE:

Step 1: Detach the Power Cable

 The disassembling of the computer system starts with externally connected device
detachment. Make sure the computer system is turned off, if not then successfully shut down the
system and then start detaching the external devices from the computer system. It includes
removing the power cable from electricity switchboard, then remove the cable from SMPS
(switch mode power supply) from the back of the CPU Cabinet. Do not start the disassembling
without detaching the power cable from the computer system. Now remove the remaining
external devices like keyboard, mouse, monitor, printer or scanner from the back of CPU cabinet.

Step 2: Remove the Cover

 The standard way of removing tower cases used to be to undo the screws on the back of
the case, slide the cover back about an inch and lift it off. The screwdrivers as per the type of
screw are required to do the task.

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Step 3: Remove the Adapter Cards

 Make sure if the card has any cables or wires that might be attached and decide if it
would be easier to remove them before or after you remove the card. Remove the screw if any
that holds the card in place. Grab the card by its edges, front and back, and gently rock it
lengthwise to release it.

Step 4: Remove the Drives

 Removing drives is easier. There can be possibly three types of drives present in your
computer system, Hard disk drive, CD/DVD/Blu-ray drives, floppy disk drives (almost absolute
now a day). They usually have a power connector anda data cable attached from the device to a
controller card or a connector on the motherboard. CD/DVD/Blu-ray drive may have an analog
cable connected to the sound card for direct audio output.

 The power may be attached using one of two connectors, a Molex connector or a Berg
connector for the drive. The Molex connector may require to be wiggled slightly from side to
side and apply gentle pressure outwards. The Berg connector may just pull out or it may
have a small tab which has to be lifted with ascrewdriver.

 Now pull data cables off from the drive as well as motherboard connector. The hard
disk drive and CD/DVD drives have two types of data cables. IDE and SATA cables. The
IDE cables need better care while being removed as it may cause the damage to drive connector
pins. Gently wiggle the cable sideways and remove it. The SATA cables can be removed easily
by pressing the tab and pulling the connector straight back.

 Now remove the screws and slide the drive out the back of the bay.

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Step 5: Remove the Memory Module

 Memory modules are mounted on the motherboard as the chips that can be damaged by
manual force if applied improperly. Be careful and handle the chip onlyby the edges. SIMMs and
DIMMs are removed in a different way.

 SIMM - Gently push back the metal tabs while holding the SIMM chips in the socket.
Tilt the SIMM chip away from the tabs until a 45% angle. It will now lift out of the socket. Put
SIMM in a safe place.

 DIMM - There are plastic tabs on the end of the DIMM sockets. Press the tabs down
and away from the socket. The DIMM will lift slightly. Now grab it by the edges and place it
safely. Do not let the chips get dust at all.

Step 6: Remove the Power Supply

 The power supply is attached into tower cabinet at the top back end of the tower. Make
sure the power connector is detached from the switchboard. Start

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removing the power connector connected to motherboard including CPU fan power connector,
cabinet fan, the front panel of cabinet power buttons and all the remaining drives if not detached
yet.

 Now remove the screws of SMPS from the back of the cabinet and the SMPS can be
detached from the tower cabinet.

Step 7: Remove the Motherboard

 Before removing all the connectors from the motherboard, make sure you memorize the
connectors for assembling the computer if required, as that may require connecting the
connectors at its place. Remove the screws from the back of the motherboard and you will be
able to detach it from the cabinet. Now remove the CPU fan from the motherboard. The heat
sink will be visible now which can be removed by the pulling the tab upward. Finally, the
processor is visible now, which can be removed by the plastic tab which can be pulled back one
stretching it side way.

ASSEMBLING:

The assembling of the computer system is exactly the opposite of disassembling

operation. Before starting assembling the computer system, make sure you have the screws and a
screwdriver for those.

Step 1: Mount the Processor

 The first step for assembling the computer system starts with mounting the processor on
the processor socket of the motherboard. To mount the process, you don't need to apply any
force. The special ZIF (zero insertion force) sockets are usually used to prevent any damage to
the processor pins. Once the processor is mounted, the heat sink will be attached on top of the
processor. The CPU fan is alsoattached on top of the heat sink.

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Step 2: Fix the Motherboard in the Tower Case

 Now the motherboard is to be fixed vertically in the tower case and the screws are fixed
from behind of the motherboard.

Step 3: Connect the Power Supply

 Now line up the power supply at the top back end of the cabinet and screw it. The power
connectors for motherboard power supply and CPU fan power supply are to be connected. If the
cabinet cooling FAN is required then it is to be screwed at the back end grill of the cabinet and
its power connector is to be connected from SMPS.

Step 4: Install the Drives

 Install the CD/DVD drives at the top front end of the cabinet and screw it. Install the
Hard disk drive and floppy disk drive below CD/DVD drive and screw it. Make sure once
screwed there is no vibration in either of the CD/DVD, hard disk or floppy disk drives.

Step 5: Connect Cables

 Now select the appropriate data cable and connect one end of the cable to its drive socket
and another end at its appropriate connector on the motherboard. For SATA hard disk drive or
CD/DVD drives use SATA cable and its power cable, else use IDE data cable. Do the proper
jumper settings as per the usage requirement.

Step 6: Mount the Memory Modules

 It is time now to mount the memory modules on the motherboard by aligning the RAM to
its socket on the motherboard and press it downward. Make sure the side tab are fixed into the
RAM notch. If not, you may still have to press a bit.

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Step 7: Install the Internal Cards

 Install the internal cards to its socket and attach the cables or power cable to it. The
selection of right socket or slot is required as per the type of socket.

Step 8: Cover the Tower

 Cover the tower by placing it and pressing towards front side and screw it.

Step 9: Connect the External Devices and Power

 Connect the external devices with CPU at its appropriate socket. It includes mouse and
keyboard at PS2 or USB connectors. Monitor at the video output socket. Connect the power cable
to the back of tower in SMPS. Plug in the power cable to the electric board.

What factors should be considered before disassembly and reassembly of acomputer?

 Shut down the computer system before the commencement of the process. It is
hazardous to perform any such activity with the computer system poweron and
connected with the power supply. Detach the power cable.

 Remove all the interfaces of the devices connected with the cabinet(computer
system).

 Perform the task at the dry, non humid area to prevent environmentalproblem.

 If you are inexperienced, take a picture of the inside assembly of the cabinet,so that you
can attach the right thing at the right place at the time of reassembly.

 Keep all the screw properly and fix all of them at the appropriate place

RESULT:

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EX NO: ASSEMBLY AND DISMANTLE OF LAPTOP

5(b)

DATE:

AIM:

To study the assemble and dismantle process of Laptop.

Parts of Laptop:

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PROCEDURE:

DISMANTLE

1. Remove the power supply and battery

Removing the battery and power adapter

 Move the locking slider to the ‘unlock’ position

 Move the other slider in the direction of the arrow

 Pull the battery out straight and not on an angle

2. Remove the accessible components

How to unscrew a laptop

 Use an appropriate magnet tipped screwdriver, most of the time you will usea Philips
screwdriver for this (see laptop disassembly tools)

 If you are removing a cover, e.g. a Hard Drive or RAM cover, it may help if you place
masking tape over the screw hole to keep the screws in place oncethe cover is removed
so as not to lose the screws.

 If the screw spins and does not come out first of all turn the laptop over and gently tap the
underside, try using the magnetic tip of the screwdriver to pullthe screw out if this helps

 If the threads on the screw have became worn then consider using a Dremel tool to drill
the screw out.

How to take the back / bottom of a laptop off

 Undo the screws from all of the covers that house the components found on the
underside of the laptop.

 The number of covers will vary from laptop to laptop. For neatness and efficiency put
the screws back into their holes on the covers once removedfrom the laptop and
consider putting some masking tape over the hole.

 There is also a single screw that retains the CD/DVD drive. On most laptopsthis
appears as a small CD picture, in this case it is the picture of a padlock. Sometimes
this screw is located underneath a cover. Try to imagine the size and length of a
CD/DVD drive to get an idea where the screw will be located. Remove this also.

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Remove the covers and lay them out upon a cleared area of your workbench in such a way that
they are positioned in rough relation to each other as they wereupon the laptop.

 HARD DRIVE: – Remove this by pulling it in the opposite direction to its data
pins. There may be screws or maybe not. The drive should pull out easily. Place it
on top of its cover in the cleared area of your desk.

 RAM: – There are clips either side of the sticks of RAM that push outward. Itis
advisable to use a plastic spudger tool whenever possible to prevent any static discharge
from occurring. When release the RAM will pop up at an angle of 30 degrees. Remove
both sticks of RAM and place them on top of their cover in the cleared area of your
desk.

 There may be more covers that you can remove or not. If you can see morethen keep
going until all covers and components have been removed.

 WIRELESS CARD: – There is a small gold tipped cover which you can priseoff with
minimum effort. This is the wireless antennae. The wireless card itself can be removed
in the same manner as the sticks of RAM. Remember to remove it at 30 degree angle.

 For now if you see a heat sink under a cover then leave it in place. If youremove it
you could damage the CPU.

3. Remove the Hinge Plate Cover (HPC) / Keyboard Bezel and keyboard

 With some laptops there are additional screws that retain the Hinge Cover Plate,
(HCP) most of the time they will be indicated by a small picture of a keyboard (but not
always). These screws will sometimes locate inside the removed battery area. Remove
them and take a note of their position and type so you can differentiate them from
other screws later on.

 Sometimes there is an obvious notch where you can begin to remove thehinge plate
cover. Using a small flat head screwdriver prize this
up. Minimum force is always required and no more. When you do this withother laptops
if you have to use more than minimum force then there are likely to be retaining screws.
STOP and remove them before you do any damage.

 Once the hinge cover plate has been prized up, use your fingers to gently remove the
whole part. Place it with the other covers on your work desk. Remove the retaining
screws found underneath the hinge cover plate. Checkfor any additional screws near the
bottom of the keyboard too.

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 The keyboard will not simply lift up you need to push it forward toward thescreen
first.

There is a ribbon cable underneath the keyboard – be very careful not topull it out at
this point.

 The ribbon cable is held in place by a plastic hinge which you can lift up usingeither your
finger nail or a plastic spudger tool.

4. Remove any other cables under the keyboard that you see

 It may be a good idea to take a picture or draw a diagram of where all thecables go.

 The ribbon cable connectors only come in a few varieties and they either prise
forward or upward. You might also see small plastic plugs for some cables. They
just pull out.

5. Remove the display unit

 Our next step will be to remove the display unit. As with most laptops beforethis can be
done we also need to remove the antennae cable and the LCD data cable. These cables
can be connected in variety of manner but removalis usually straight forward.

 Take out the hinge screws for the display assembly. Sometimes they are onthe back and
others they are inside. Try to see where the hinges might be connected, they usually use
longer screws.

 Take out the hinge screws for the display assembly and gently removed thepart.

SCREEN REPLACEMENT / FL INVERTER

 Remove the black rubber pads from around the edge of the screen surround. The
retaining screws are to be found under here. When removing
the pads using as little force as possible as to not damage them. Try and useyour finger
nails at first before resorting to other tools.

 Undo the screws and place them into a tub on your separate work area.

 Using a spudger tool or your fingers pry the front cover away from the backpart of the
screen. Run the spudger tool around the outside if required but

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at no point should you feel resistance, you may have missed a screw if youdo.

 With the front cover removed the LCD screen is now exposed.

 Remove the tiny screws from the side of the LCD screen and remove the screen
taking care not to touch the back part of the screen that says ‘DONOT TOUCH’.

 Most laptops allow you to just remove 2 screws from the top front part of themetallic
arms that hold the LCD in place which allows you to tilt the screen and have access to
the FL INVERTER.

6. Pry case apart

 Pry case apart – use spudger, fingernails or plastic tools. Again, if you feelresistance
STOP and double check you have removed all of the screws.

7. Remove the motherboard and motherboard peripherals

 Take note that the touchpad comes as part of an assembly and when you buy a
replacement one of these it comes as the assembly and not just thetouchpad.

 Remove all screws securing the system board, the power board, the videoboard, etc.
Disconnect all cables, connecting the boards.

 Sometimes the screws on the motherboard have a letter assigned or white arrows. They
are the ones you have to unscrew to get the motherboard off because you don’t always
have to take all the screws out.

 Take the screw numbers as a guide for fitting and removal.

 Slowly take the motherboard out and feel for where the pressure seems to keep the
board in place. It should come out with no pressure.

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ASSEMBLE:

STEP 1

 Put the motherboard back into the case and reconnect the sound cable.

 Put all screws back into the white arrow holes.

 Put the case parts back together. Remember to thread the cables including the antennae
cable back through. Make sure no cable is snagged or caught up anywhere.

STEP 2

 Put the retaining screws back into the bottom half of the laptop. Then putthe top
screws back in.

STEP 3

 Put the screen back in place and reconnect the antennae and the data cable.

 Replace the display hinge screws.

STEP 4

 Replace the keyboard. First of all put the ribbon cable back in. Remember there is a
plastic hinge which holds the ribbon in place; remember to lift thisup first (gently).

 The ribbon has a darker side and a lighter side. It is the lighter side thatfaces
upward, so there is no twist in the ribbon.

 Replace the keyboard retaining screws.

STEP 5

 Click the Hinge Cover Plate (HCP) back into place. Use even pressure toensure it
fits properly.

STEP 6

 Replace the RAM. Remember it is fed into the slots at 30 degree angles andnot straight
on.

 Once it has been fed at a 30 degree angle, click it downwards into place.

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 Replace the other components such as the wireless card, again remember it has to insert
at a 30 degree angle. Click it into place and gently replace the gold connector.

 Replace the Hard Disk Drive (HDD) by sliding it in the opposite direction tothe
arrow. Make sure it fits securely and is not loose.

 Insert the CD/DVD drive and put the retaining screw back into the undersideof the
laptop.

STEP 7

 Finally, replace the component covers and replace all of the screws.

These steps give you a generic overview that you can use to take any laptop apart.

RESULT:

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EX NO: 6 STUDY OF WASHING MACHINE

DATE:

AIM:

To Study of washing machine .

Types of washing machine:

 Front-load
 Top-load
 Semi-automatic

Front load
The door is on the front of the machine, and the drum is horizontal. Front-load machines are more
efficient and gentler on clothes, but they may cost more upfront.

Top load
The door is on the top of the machine, and the basket is vertical. Top-load machines are usually
cheaper, but they may have a smaller capacity. They are also a good option for people with mobility
issues.

Semi-automatic
Semi-automatic machines require the user to intervene at one or two points in the wash
cycle. Some semi-automatic machines have two tubs, one for washing and one for rinsing.

Other types

 Washer-dryer: A combination washer-dryer is good for small spaces, but it may not have many
features.
 Compact or portable: These machines are smaller and more portable.

Components of washing machine:

 Water pump
 Agitator/paddles Control panel
 Drain pipe.
 Motor
 Heating element
 Water inlet valve
 Circuit board
 Tub/drum
 Timer

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Water pump

The water pump is located inside the washer, so you can’t actually see it. The pump has a double
duty of circulating water during the cycle as well as draining the water once the cycle is complete. Some
machines may have two different pumps–one that just pumps water, and one that drains. This will vary by
model of the washer.

Water pump

Drain pipe
Usually sitting close to the drain pump, the drain pipe will rid all the dirty water from washing a
load of laundry out of the tub.

Drain pipe

Water inlet control valves

Located near the water inlet point. These valves open and close depending on the size of the load and
how much water needs to be dispensed for a wash cycle.

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Water inlet control valves

Tub/drum

There are technically two tubs in your washer. The first one is a movable, perforated tub where the
clothes are placed. The perforated surface allows for water to come in and out during the cycle. The outer
tub supports the inner tub and also holds water during the washing cycle.

Tub/drum

Agitator/impeller/lifter

Whether you have an agitator or impeller depends on the model of your washing machine. Regardless
of what kind you have, they are located on the inside of the inner tub of your washer, and they are an
essential part of cleaning your clothes. Their movements cause clothing to move and rub against each
other, which in turn lifts dirt and stains from fabric.

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Agitator/impeller/lifter

Washing machine motor

The washing machine motor powers the movement that causes your agitator, discs or drum to
rotate as your machine runs through a cycle. Washing machines use a variety of motors, including direct
drive motors, brushless DC motors, and inverter motors.

Washing machine motor

Printed circuit board

The printed circuit board (PCB) is the brains of the washing machine. It commands the control
panel and wash cycles, as well as firing off the different electronic parts that are needed for your washer
to do its job. The PCB is also responsible for water levels, how much detergent is dispensed and other
functions your washing machine may have.

Printed circuit board

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Timer
Timers on washing machines can either be set manually or automatically, and will set the wash
time for your laundry cycles. Not all washers come with a timer, so your washer may not have this
feature.

Timer

Control panel
All your settings and wash cycles will be controlled on this panel, which is either on top or front
of the washing machine.

Control panel

Heating element
The element plays an important role in keeping your appliance running, as it ensures the water is
hot during the wash (if the water is not heated the machine may wash continuously and not finish a
cycle).

Heating element

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Working principle of washing machine

The working principle of a washing machine is based on the combination of mechanical agitation, water,
detergent, and electrical power to clean clothes.
1. Water Supply and Detergent: The washing machine first fills with water (either hot or cold)
depending on the settings. Detergent is added to the water, either manually or automatically, to
help break down dirt and stains on the clothes.
2. Agitation: Once the drum is filled with water and detergent, the motor spins the drum or agitator.
In top-load machines, an agitator (a central post with fins) moves the clothes through the water,
creating friction to loosen dirt. In front-load washers, the drum tilts and rotates, tumbling the
clothes through the water.
3. Cleaning Action: As the clothes move around in the soapy water, dirt and grime are removed
from the fabric. The agitation helps in lifting and scrubbing the clothes against each other.
4. Rinsing: After washing, the machine drains the soapy water and refills with clean water to rinse
the clothes, removing any detergent residues. This is usually repeated once or twice.
5. Spinning (Extracting Water): After rinsing, the machine enters the spin cycle, where the drum
spins at a high speed to extract as much water as possible from the clothes. This is done by
centrifugal force, which forces the water out of the fabric.
6. Draining: Finally, the washer drains the remaining water, and the cycle ends. The clothes are now
clean and ready to be removed for drying.

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DISMANTLINGWAYSOFMAINPARTS

Step 1: Remove the knobs

 Take out the knobs directly because knobs are inserted into the control panel.
 If it is difficult to take knobsout, a straight screw driver wrapped with cloth can be used for help.

Remove the knobs

Step 2: Remove the control panel

 Take down the back cover by loosen-ing off the screws.

 Take down the bag by cutting off the nylon clip. Take down
 all wire nut with a plier and make all wire clamps loose.And then unfastenthedrainbeltconnector.
 Unfasten the screws on the control panel.
 Thecontrol panel can be lifted and removed

Remove the control panel

Step 3: Remove the pulsator

 Unscrewthepulsatorscrew.
 Draw out the pulsator with hands.

Remove the pulsator

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Step 4: Remove the lint filter

 Press the lint filter subassemblythen pull it out.

Remove the lint filter

Step 5: Remove the frame

 Screw offfixing screws of the frame.

 Screw offscrews under the handles at both sides of the frame.
 Screw off the stainless steel screw on the top surface of theframe.
 Theframecanberemoved.

Remove the frame

Step 6: Remove the spin tub

 Unscrew the fixing screw under the tub with a socket wrench.
 The spin tub can be removed then.

Remove the spin tub

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Step 7: Remove the motor pulley
 Loosen the nut with special wrench,then loosen the screw.

Remove the motor pulley

How to use a washing machine: The dos & don'ts

1. DO separate colours and pre-treat stains.

2. DO check garment care labels.
3. DO put delicates in laundry bags.
4. DO put detergent in the right place.
5. DO leave your washing machine door open after use.
6. DO Clean your washing machine.
7. DON'T overload your machine.

Result:

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