University of Engineering and Technology, Lahore
(Narowal Campus)
Submitted To:
Engr. Osama Bin Naeem
Submitted By:
Zubair Usman
Registration No:
2020-EE-630
Subject:
Electrical and Electronics Workshop
Department:
Electrical Engineering
LAB MANUAL
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Lab 1. To Understand & Draw the symbols of various electronic devices
Sr. No.
Device Name
Resistor
1.
Variable resistor
2.
Capacitor
3.
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4.
Electrolyte (polarized) Capacitor
5.
Variable capacitor
Symbol
6.
Inductor
7.
Transformer
8.
9.
10.
11
DC power supply
Ground
AC supply
voltmeter
Current meter
12.
13.
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CRO
14.
ohm meter
PN junction diode
15.
Zener diode
16.
Tunnel diode
17.
Light Emitting diode(LED)
18.
Seven segment display
19.
Photo diode
20.
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npn transistor
21.
22.
pnp transistor
Photo transistor
23.
Optocoupler
24.
25.
Thermistor
LDR(Light Dependent Resistor)
26.
UJT(Uni Junction Transistor)
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27.
n-type
UJT(Uni Junction Transistor)
28.
p-type
SCR(Silicon Controlled Rectifier)
29.
DIAC
30.
TRIAC
31.
32
n-channel JFET
p-channel JFET
33.
n-channel depletion MOSFET
34.
35
p-channel depletion MOSFET
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n-channel enhance MOSFET
36.
p-channel enhance MOSFET
37.
Relay
38.
39.
DC Supply
40.
AC Supply
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Sr. Device Name
No.
1. Resistor
Uses
Resistors are electrical components that helps to control the flow
of current in circuit.
Sometimes resistors are used as a voltage divider.
2.
A variable resistor used in a potentiometer to adjust low-pass and
high-pass filters. A variable resistor used in LDR's which change
its resistance proportional to th lights it gets.
Variable
Resistor
3. Capacitor
Capacitors are used in almost all electronics products in a variety
of ways.
Capacitors can be used in a time-dependent circuits because their
charging & discharging take place at regular intervals.
4. Electrolyte
They can be used for reducing voltage fluctuations in filtering
device.
They can be used to provide time delay b/w two functions in a
circuit.
(polarized)
Capacitor
5.
These are frequently used in numerous circuits through the
microwave.
These capacitors are applicable in medical instrument like NMR
scanner, MRI to generate extremely high magnetic field.
Variable
capacitor
6. Inductor
7.
Symbol
Inductors are used in tunning circuits, with the help of inductor the
tuning circuit select the desired frequency.
Inductors can store energy for a small period of time because the
energy which i being stored as a magnetic field will be gone when
the power supply is removed.
Transformer
It can rise or lower the level of level of voltage or current
in an AC circut. It can be used to prevent DC from
passing from one circut to another
DC current is easier for smaller devices to utilize and is the most
commen method for power supply.
DC
8. supply
power
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Many devices, such as computers stereos, and other smaller
electrical appliance have their DC converting rectifier built right into
the device.
Ground terminal is used for the protection and safety purpose
alone, it has nothing to do with circuit.
9.
Ground
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AC is generally used for power distribution, which is why the main
sockets in ou homes and at work provide an alternate current.
10.
AC supply
Alternate Current is mainly used in the industry of the
transportation and production of electricity.
Voltmeters can be used to measure the voltage drop across a
single component o supply, or they can be used to measure the
sum of voltage drops two or more points or components within a
circuit.
11.
voltmeter
12. Current meter
The instrument is used for the accurate determination of current
velocity in wate ways,channels, rivers and the sea.The meter can
also be applied in polluted wate currents.The measurements are
executed with the propeller mounted on the rod(s) o connected to
a cable.
The CRO is used to measure the voltage, current, frequency,
inductance, admittance resistance, and power factor.
13.
CRO
This device is used to monitor the signal properties as well as
characteristics and also controls the analogs signals.
Ohmmeter, instrument for measuring electrical resistance, which
is expressed in ohm. In the simplest ohmmeter, the resistance to
be measured may be connected to the instrument in parallel or in
series.
14.
ohm meter
PN
15.
16.
junction
diode
Zener diode
17. Tunnel diode
PN junction diode can be used as a photo diode as the diode is
sensitive to the ligh when the configuration of the diode is
reversed-based.
It can be used as a solar cell.
Zener diode is used for voltage regulation, as referance elements,
surge suppressors and is switching applications and clipper
circuits. The load voltage equals breakdown voltage VZ of the
diode.
Tunnel diode can be used as a switch, amplifier and oscillator.
They are used in oscillator circuits, and in FM receivers.
Tunnel diode acts as logic memory storage device.
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18.
Light
Emitting
diode(LED)
The major uses of LED are illuminate objects and even places.
Its applications is everywhere,
*TV Backlighting
*LED displays
19. Seven
Segment
display
*Dimming of lights etc.
A seven segment display is a form of electronic display device for
displaying decimals numerals that is an alternative to the more
complex dot matrix displays.Seven segment displays are widely
used in digital clocks, electronic meters basic calculators and other
electronic devices that display numerical information.
Photo diode are used in consumer electronics devices such as
compact disc players smoke detectors, medical devices and the
receivers for infrared remote contro devices used to control
equipment from televisions to air conditioners.
20.
Photo diode
npn transistor
21.
22. pnp transistor
23. Photo transistor
24.
Optocoupler
*
NPN transistors are mainly used in switching applications.
*
Used in amplifying circuits applications.
*
Used in the Darlington pair circuits to amplify weak signals.
* PNP transistors are used to source current, i.e. current
flows out of collector.
*
Used as a switches.
*
They are used in the amplifying circuits.
* PNP transistors are used when we need to turnoff
something by push a button.
The photo transistor is widely used in electronics devices like
smoke detectors infrared receiver, lasers etc. For sensing light.
They also find applications in Opto-isolators, position sensing,
security system, Coin counter, etc.
The Optocoupler is a device that contains an infrared LED and a
photodetector(such as a photo diode) combined in one package.
25.
Thermistor
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The most common industrial use of the optocouplers is as a signal
converter b/w high voltage pitot devices and low voltage solid-state
logic circuits.
Thermistors are used as temperature sensors. They can be found
in every day appliances such as fire alarms, ovens and
refrigerators.
They are also used in digital thermometers and in many automotive
applications to measure temperature.
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26.
LDR(Light
Dependent
Resistor)
27. UJT(Uni
Junction
Transistor) ntype
These devices are used where there is a need to sense the
presence and absence o light is necessary. These resistors are
used as light sensors and the applications o LDR mainly include
alarm clocks, streets lights, light intensity meters, burgla alarm
circuits.
It is used in free-running oscillators, synchronized or triggered
oscillators, and pulse generation circuits at low to moderate
frequencies (hundreds of kilohertz). It is widely used in the
triggering circuits for silicon controlled rectifiers.
28. UJT(Uni
Junction
Transistor) ptype
The most common application of a unijunction transistoris as a
triggering device for SCR's and Triacs but other UJT applications
include sawtoothed generators, simple oscillators, phase control,
and timing circuits.
29.
SCRs are mainly used in devices where the control of high power,
possibly coupled with high voltage, is demanded. Their operation
makes them suitable for use in medium- to high-voltage AC power
control applications such as lamp dimming, power regulators and
motor control.
SCR(Silicon
Controlled
Rectifier)
30.
DIAC
The DIAC is an electronics component that is widely used to assist
even triggering of a TRIAC when used in AC switches and as a
result they are often found in light dimmers such as those used in
domestic lighting. These electronic components are also widely
used in starter circuits for fluorescent
TRIAC (Triode for AC) is a semiconductor device widely used in
power control and switching applications. It finds applications in
switching, phase control, chopper designs, brilliance control in
lamps, speed control in fans, motors, etc.
31.
TRIAC
The big point is that, an N-Channel JFET turns on by having a
positive voltage applied to the drain terminal of the ideally no voltage
applied to the gate terminal. The transistor circuit shuts off by
taking in a negative gate voltage, VGS, greater than about -4V or
so.
32
n-channel JFET
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,
The big point is that, a P-Channel JFET turns on by having a
positive voltage applied to the source terminal of the transistor
and ideally no voltage applied to the gate terminal. The transistor
circuit shuts off by taking in a positive gate voltage, VGS, above
about +4V or so.
33. p-channel JFET
n-channel
depletion
34. MOSFET
35 p-channel
depletion
MOSFET
nchannel enhance
36. MOSFET
pchannel enhance
MOSFET
37.
38. Relay
39. DC Supply
40. AC Supply
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N-Channel MOSFET is a type of metal oxide semiconductor
field-effect transistor that is categorized under the field-effect
transistors (FET). MOSFET transistor operation is based on the
capacitor. This type of transistor is also known as an insulatedgate field-effect transistor (IGFET).
When the gate voltage reaches a certain negative voltage
threshold, it shuts the transistor off. Negative voltage shuts the
transistor off. This is for a depletion-type P-channel
MOSFET.MOSFET transistors are used for both switching and
amplifying applications.
In this circuit, using enhanced mode, a N-channel MOSFET is
being used to switch the lamp for ON and OFF. The positive
voltage is applied at the gate of the MOSFET and the lamp is ON
(VGS =+v) or at the zero voltage level the device turns off
(VGS=0).
This will allow a current to flow through the source-drain channel.
So with sufficient positive voltage, VS, to the source and load, and
sufficient negative voltage applied to the gate, the P-Channel
Enhancement type MOSFET is fully functional and is in the active
'ON' mode of operation.
Relays are used to provide time delay functions. They are used to
time the delay open and delay close of contacts.Relays are used
to control high voltage circuits with the help of low voltage signals.
Similarly they are used to control high current circuits with the help
of low current signals.
Direct current has many uses, from the charging of batteries to
large power supplies for electronic systems, motors, and more.
Very large quantities of electrical energy provided via directcurrent are used in smelting of aluminum and other
electrochemical processes.
Alternating current, AC is generally used for power distribution,
which is why the mains sockets in our homes and at work provide
an alternating current to power whatever is needed, but direct
current, DC is more widely used for the electronics boards
themselves and for many
Lab 02:
To identify resistors, capacitors using different codes.
1. To study different types of resistors and coding
Object
1. To learn Resistor Color Code
2. To determine the stated value of a resistor by interpreting the color code indicated on
the resistor. Apparatus
1. Set of wires.
2. Carbon Resistors.
3. Digital A.V.O. meter.
Theory
The resistor's function is to reduce the flow of electric current. This symbol is used to
indicate a resistor in a circuit diagram. Resistance value is designated in units called
the "Ohm." A 1000 Ohm
resistor is typically shown as 1K-Ohm (kilo Ohm), and 1000 K-Ohms is written as 1MOhm
(Mega
ohm).
There are two classes of resistors; fixed resistors and the variable resistors. They are
also classified according to the material from which they are made. The typical resistor
is made of either carbon film or metal film. There are other types as well, but these are
the most common.
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The resistance value of the resistor is not the only thing to consider when selecting a
resistor for use in a circuit. The "tolerance" and the electric power ratings of the resistor
are also important. The tolerance of a resistor denotes how close it is to the actual rated
resistance value. For example, a ±5% tolerance would indicate a resistor that is within
±5% of the specified resistance value
The power rating indicates how much power the resistor can safely tolerate. The
maximum rated power of the resistor is specified in Watts. Power is calculated
using the square of the current (I2) x the resistance value (R) of the resistor. If the
maximum rating of the resistor is exceeded, it will become extremely hot and even
burn. Resistors in electronic circuits are typically rated 1/8W, 1/4W, 1/2W, 1W and
2W. 1/8W is almost always used in signal circuit applications. When powering a
light emitting diode, a comparatively large current flow through the resistor, so you
need to consider the power rating of the resistor you choose.
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Fixed Resistors
Fixed resistors are one type of linear resistors. A resistor is said to be a fixed
resistor, if its value is fixed. The value of fixed resistor can't be varied like a variable
resistor as its value is determined at the time of manufacturing itself. The following
figures represent the symbol of a fixed resistor.
Carbon film resistor
Carbon film resistors are a fixed form type resistor. They are constructed out of a
ceramic carrier with a thin pure carbon film around it, that functions as resistive material.
Metal film resistor
Metal film resistors have a thin metal layer as resistive element on a non-conducting
body. They are amongst the most common types of axial resistors. Other film type
resistors are carbon film and thick and thin film resistors. In most literature referrals to
metal film, usually it is a cylindrical axial resistor.
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Variable Resistors
A variable resistor is a resistor of which the electric resistance value can be adjusted. A
variable resistor is in essence an electro-mechanical transducer and normally works by
sliding a contact (wiper) over a resistive element.
Resistor coding
There are two types of codes used for identification of values of resistors.
Color coding
Resistor Color Coding uses colored bands to quickly identify a resistors resistive value
and its percentage of tolerance with the physical size of the resistor indicating its wattage
rating.
Generally, the resistance value, tolerance, and wattage rating are printed on the body of a
resistor as numbers or letters when the resistors body is big enough to read the print,
such as large power resistors.
Character coding
Characters are also used for coding the resistor. The characters used for coding are E,
K, M, and
R.
When character comes in between two decimal numbers, it acts as a decimal point. The
letter E indicates Ohms only, K indicates Kilo ohms and M indicates Mega ohms. e.g. .
2E5 = 2.5 Ω
.3K9 = 3.9 KΩ
.9M7 = 9.7 MΩ
.23E = 23Ω
.1K = 1 KΩ
.2M = 2MΩ
.22M3 = 22.3MΩ
.R3 = 0.3 Ω
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2. To study different types of capacitors and coding.
Theory
The capacitor's function is to store electricity, or electrical energy. The
capacitor also functions as a filter passing alternating current (AC), and
blocking direct current (DC). This symbol is used to indicate a capacitor in a
circuit diagram. The capacitor is constructed with two electrode plates facing
each other, but separated by an insulator. When DC voltage is applied to the
capacitor, an electric charge is stored on each electrode. While the capacitor
is charging up, current flows. The current will stop flowing when the capacitor
has fully charged.
Breakdown Voltage
The capacitance of a capacitor is proportional to the surface area of the plates
(conductors) and inversely related to the gap between them. In practice, the dielectric
between the plates passes a small amount of leakage current. It has an electric field
strength limit, known as the breakdown voltage.
Electrolytic Capacitors
An electrolytic capacitor is a polarized capacitor whose anode or positive plate is
made of a metal that forms an insulating oxide layer through anodization. This oxide
layer acts as the dielectric of the capacitor. ... The failure of electrolytic capacitors can
be hazardous, resulting in an explosion or fire.
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Tantalum Capacitors
A tantalum electrolytic capacitor is an electrolytic capacitor, a passive component of
electronic circuits. It consists of a pellet of porous tantalum metal as an anode, covered
by an insulating oxide layer that forms the dielectric, surrounded by liquid or solid
electrolyte as a cathode. Because of its very thin and relatively highpermittivity dielectric
layer, the tantalum capacitor distinguishes itself from other conventional and electrolytic
capacitors in having high capacitance per volume (high volumetric efficiency) and lower
weight.
Ceramic Capacitors
A ceramic capacitor is a fixed-value capacitor where the ceramic material acts as the
dielectric. It is constructed of two or more alternating layers of ceramic and ametal layer
acting as the electrodes. The composition of the ceramic material defines the electrical
behavior and therefore applications. Ceramic capacitors are divided into two application
classes:
•
Class 1 ceramic capacitors offer high stability and low losses for resonant circuit
applications.
•
Class 2 ceramic capacitors offer high volumetric efficiency for buffer, by-pass, and
coupling applications.
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Capacitor coding
The value of a capacitor (the capacitance), is designated in units called the Farad (F).
The capacitance of a capacitor is generally very small, so units such as the microfarad
(10-6F), nanofarad (10-9F), and picofarad (10-12F) are used. The method used differs
depending on the capacitor supplier. Also for different types of capacitors the coding is
different. For example, on electrolytic capacitors the value is directly printed on the
capacitor. For ceramic capacitor there are four types of codings.
1- using numbers
2- using letter and numbers both
3- directly printed for uF
Coding using numbers
A three-digit code is used to indicate the value of a capacitor. In the case that the value
is displayed with the three-digit code, the 1st and 2nd digits from the left show the 1st
figure and the 2nd figure, and the 3rd digit is a multiplier which determines how many
zeros are to be added to the capacitance
Pico farad (pF) units are written this way.
For example,
[103] indicates 10 x 103
, or 10,000pF = 10 nano farad (nF) =0.01microfarad (µF).
[224] indicates 22 x 104 or 220,000pF=220nF=0.22µF.
Values under 100 pF are displayed with 2 digits only . For example 47 would be 47
pF.
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Coding using letters and numbers both
When letter K comes in between two digits, it acts as a decimal point. Picofarad (pF)
units are also written this way.
For example,
[3K3] indicates 3.3k=3300 pF=3.3nF. [1k] indicates 1k=1000pF=1nF,
[33k] indicates 33k=33000pF=33nF.
Directly printed for microfarad
If decimal dot is given in the code, directly consider the value in microfarad.
For example,
[0.1] indicates 0.1 µF,
[0.22] indicates 0.22 µF
[0.47] indicates 0.47 µF
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Lab 03
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To study digital multimeter and perform tasting of various components
Tools Required
1- Digital multimeter
2- Resistors
3- Diode
4- p-np and n-p-n transistors
Voltage / Current test
Electrical testing in its most basic form is the act of applying a voltage or current to a
circuit and comparing the measured value to an expected result. Electrical test
equipment verifies the math behind a circuit and each piece of test equipment is
designed for a specific application.
It is the job of a test technician to know which piece of test equipment to use for the task
at hand and also understand the limitations of the test equipment they are using. In this
article, we take a look at the most common pieces of test equipment used in the field.
Resistance test
Measuring resistance with a digital multimeter is easier and faster than making a
resistance measurement with an analogue multimeter as there is no need to zero the
meter. As the digital multimeter gives a direct reading of the resistance measurement,
there is also no equivalent of the reverse reading found on the analogue multimeters.
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There are a few simple steps required to make a resistance measurement with a digital
multimeter:
1. Select the item to be measured: This may be anything where the resistance needs
to be measured and estimate what the resistance may be.
2. Insert the probes into the required sockets
Often a digital multimeter will have
several sockets for the test probes. Insert these or check they are already in the
correct sockets. Typically these might be labelled COM for common and the other
where the ohms sign is visible. This is normally combined with the voltage
measurement socket.
3. Turn on the multimeter
4. Select the required range The digital multimeter needs on and the required range
selected. The range selected should be such that the best reading can be obtained.
Normally the multimeter function switch will be labelled with the maximum
resistance reading. Choose the one where the estimated value of resistance will
be under but close to the maximum of the range. In this way the most accurate
resistance measurement can be made.
5. Make the measurement With the multimeter ready to make the measurement the
probes can be applied to the item that needs to be measured. The range can be
adjusted if necessary.
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Diode testing
•
A good forward-based diode displays a voltage drop ranging from 0.5 to 0.8 volts
for the most commonly used silicon diodes. Some germanium diodes have a
voltage drop ranging from 0.2 to 0.3 V.
•
The multimeter displays OL when a good diode is reverse-biased. The OL
reading indicates the diode is functioning as an open switch.
•
A bad (opened) diode does not allow current to flow in either direction. A
multimeter will display OL in both directions when the diode is opened.
•
A shorted diode has the same voltage drop reading (approximately 0.4 V) in both
directions.
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Continuity test
•
Continuity is the presence of a complete path for current flow. A circuit is
complete when its switch is closed.
•
A digital multimeter’s Continuity Test mode can be used to test switches, fuses,
electrical connections, conductors and other components. A good fuse, for
example, should have continuity.
•
A DMM emits an audible response (a beep) when it detects a complete path.
•
The beep, an audible indicator, permits technicians to focus on testing
procedures without looking at the multimeter display.
•
When testing for continuity, a multimeter beeps based on the resistance of the
component being tested. That resistance is determined by the range setting of the
multimeter. Examples:
o If the range is set to 400.0 Ω, a multimeter typically beeps if the
component has a resistance of 40 Ω or less.
o If the range is set 4.000 kΩ, a multimeter typically beeps if the component
has a resistance of 200 Ω or less.
•
The lowest range setting should be used when testing circuit components that
should have low-resistance value such as electrical connections or switch
contacts.
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Identifying the leads and polarity of unknown bipolar transistors
The type (PNP or NPN) and the lead arrangement of unmarked transistors can be
determined easily using a digital or analog multimeter, if the transistor is seen as a pair
of connected diodes. The collector and emitter can be identified knowing the fact that
the doping for the B-E junction is always much higher than for the B-C junction,
therefore, the forward voltage drop will be slightly higher. This will show up as a couple
of millivolts difference on a digital multimeter's diode test scale or a slightly higher
resistance on an analog Volt OhmMeter.
First make the a few measurements between various leads. Soon you'll identify a lead
(the Base) that will show a forward voltage drop (on DMMs) combined with two other
leads (the Emitter and Collector). Now that the Base is identified, observe carefully the
voltage drops across B-E and B-C.
The B-C junction will have a slightly less voltage drop.
If you arrived at this point, you already know the polarity of the transistor under test. If
the negative lead (black lead connected to the COM on most digital multimeters) is
placed on the Base when measuring the B-C and B-E voltage drops - you have a PNP
transistor. Similarly - if the positive meter lead is placed on the base, you have a NPN
transistor.
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Lab 4: To Study Soldering and De-soldering Techniques
SOLDERING:
Soldering is a technique in which two or more metal items are joined
together by melting and flowing a filter metal having a lower melting point than
the adjoining metal.
REQUIRED TOOLS FOR SOLDERING:
1. Solder Iron
2. Solder wire
3. De-soldering pump
4. Flux
5. PCB
Solder iron
Fig.4.1
6. Different electronic components
SOLDER:
It is an instrument, a low-melting alloy, especially one based on lead and tin or
on brass and silver, used for joining less fusible metals by creating permanent
bond.
FLUX:
Flux is a chemical used before and during soldering of electronic components
onto the circuit boards.
The flux also protects the metal surfaces from re-oxidation during soldering and
helps the soldering process by altering the surface tension of the molten solder.
Fig 4.2 Flux
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SOLDERING TECHINQUES:
Soldering techniques can be broadly classified in two groups:
1. Iron soldering or Manual soldering
2. Mass soldering or Automatic soldering
Manual soldering requires solder iron, solder wire, flux and electronic
components.
SOLDERING
1.
Take one PCB (Printed Circuit Board), solder iron, solder wire and
electronic components and give supply to solder iron.
2.
Place the iron at the angle of 45 degree, with the tip touching as
many elements of the joints as possible.
3.
Place the solder wire near the iron and let it flow. Pass it around the
joints.
4.
Remove the iron and let the solder flow in the area from where the
iron has been removed.
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5. When the solder has successfully flowed in the lead and track, take
the solder away and then remove the iron
.
DESOLDERING
To de
- solder means to remove a joint or re
- position
a wire or component.
There are two ways to remove the solder:

WITH A DE
- SOLDER PUMP (SOLDER
SUCKER)
1. Use a soldering iron or another heated
air source to melt the solder.
2. Placing the solder pump’s tip as close
to the solder as possible, press the
release
button . Ensure you keep the
pump’s tip steady and in place as the
pump suctions the melted solder.
Fig 4.4 De - soldering with pump
3. Repeat until all solder is removed from the component and circuit
board.
4. Using pliers, remove the part from
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the motherboard.
WITH SOLDER REMOVE WICK (COPPER BRAID):
1. Unwind a few inches of braid from the coil.
2. If your solder wick does not have flux on it, it would be a good idea to add
flux to the section which is going to used to make for a clean removal.
3. Place the braid over the joint you want to rework.
4. Place a hot soldering iron against the braid and desired pin.
Fig 4.5 De-soldering with wick
5. Wait a few seconds. The solder will flow off the pin and onto the braid.
6. Remove the braid. The braid will be very hot at this point, so make sure
not to touch the braid itself, only the spool.
7. Remove the component.
8. Repeat steps 1-5 to remove excess solder.
Fig 4.5 De-soldering with copper braid
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Lab 5.
Printed Circuit Board (PCB) making
CIRCIUT BOARD:
It is a thin board containing an electric circuit, a printed circuit.
THEORY

A printed circuit board (PCB) mechanically supports and
electrically connects electrical or electronic components using
conductive tracks, pads and other features etched from one or more
sheet layers of copper laminated onto and/or between sheet layers of a
nonconductive substrate. Components are generally soldered onto the
PCB to both electrically connect and mechanically fasten them to it.

Printed circuit boards are used in all but the simplest electronic
products. They are also used in some electrical products, such as
passive switch boxes.

Alternatives to PCBs include wire wrap and point-to-point
construction, both once popular but now rarely used. PCBs require
additional design effort to lay out the circuit, but manufacturing and
assembly can be automated. Electronic computer-aided design
software is available to do much of the work of layout. Massproducing
circuits with PCBs is cheaper and faster than with other
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wiring methods, as components are mounted and wired in one
operation. Large numbers of
PCBs can be fabricated at the
same time, an
d the layout only
has to be done once. PCBs can
also be made manually in small
quantities, with reduced benefits.

PCBs can be single
- sided (one
copper layer), double
- sided (two
copper layers on both sides of
one substrate layer), or multi
( outer and
- layer
inner layers of copper,
alternating with layers of substrate).

Fig 5.1 Layers of PBC
Multi - layer PCBs allow for much higher component density, because
circuit traces on the inner layers would otherwise take up surface
space between
components. The rise in popularity of multilayer PCBs
with more than two, and especially with more than four, copper
planes was concurrent with the adoption of
technolog
surface mount
y . However, multilayer PCBs make repair, analysis, and
field modification of circuits much more difficult and usually
impractical.
REQUIRED TOOLS:
 Drilling machine
 Ferric chloride
Circuit Diagram
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Pattern Circuit
PROCEDURE FOR PRINTING PCB
Fig 5.2 Flow chart
INITIAL PREPRATION:
PCB design is usually done by converting your circuit’s schematic diagram
into a PCB layout using PCB layout software. There are many cool open
sources software packages for PCB layout creation and design.
Fig 5.3 Copper sheet
The initial preparation requires making of a negative transparency
of the pattern to the actual PCB size. The already prepared layout of PCB
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can also be transferred to the transparent sheet. The pattern can also be
drawn if not available which may be bigger than the actual PCB size but
can be reduced similar to original one.
The task of transferring the pattern can be accomplished by using a
printing or photo copier machine.
PAINTING:
Transfer the actual size PCB pattern on the copper clad board with the help of
carbon paper and painted with a paint where copper track is needed considering
the PCB pattern. Dried it for one hour now the PCB is ready for etching.
Fig 5. Printing track on copper plate
ETCHING
Etching is a "subtractive" method used for the production of printed circuit
boards: acid is used to remove unwanted copper from a prefabricated laminate.
This method involves chemical solvents like Ferric chloride (FeCl3) OR Cupric
Chloride (CuCl2). This is done by applying a temporary mask that protects parts
of the laminate from the acid and leaves the desired copper layer untouched.
Fig 5.4 Etching
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PAINT REMOVAL:
Once the etching job is completed remove the paint resist from the image area
with turpent oil. Wash the cleaned surfaces thoroughly and dry quickly.
Fig 5.
Cleaning of
plate
FINISHING:
At this stage the PCB is ready for the final operation of drilling the holes. Drill
the holes of required size at the appropriate places, place and solder the
components properly and test it.
Fig 5. Drilling
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TASK:
DEGISNING OF PCB/ LAYOUT BY USING PCB EDITOR
THEORY

A printed circuit board (PCB) mechanically supports and
electrically connects electrical or electronic components using conductive
tracks, pads and other features etched from one or more sheet layers of
copper laminated onto and/or between sheet layers of a nonconductive
substrate. Components are generally soldered onto the PCB to both
electrically connect and mechanically fasten them to it.

Printed circuit boards are used in all but the simplest electronic
products. They are also used in some electrical products, such as
passive switch boxes.
REQUIRED TOOL:
Proteus (stimulation software)
TYPES OF PCB
BREADBOARD:
A breadboard is a widely used tool to design and test circuit.
There is no need to solder wires and components to make a circuit while using a
bread board. It is easier to mount components & reuse them.
Since, components are not soldered so the circuit design can be changed at any
point without any hassle.
A typical bread board layout consists of two types of region also called strips.
Bus strips and socket strips. Bus strips are usually used to provide power supply
to the circuit. It consists of two columns, one for power voltage and other for
ground.
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Fig 6.1 Bread board
VERO BOARD:
Veroboard is a brand of stripboard, a pre-formed circuit board
material of copper strips on an insulating bonded paper board which was
originated and developed in the early 1960s by the Electronics Department of
Vero Precision Engineering Ltd (VPE).
It was introduced as a general-purpose material for use in constructing
electronic circuits - differing from purpose-designed printed circuit boards
(PCBs) in that a variety of electronic circuits may be constructed using a
standard wiring board.
It is used to make electronic circuits, where some of the electrical connections
are formed by strips of copper on the underside of the board. It is characterized
by a 0.1inch regular grid of holes, with wide parallel strips of copper cladding
running in one direction all the way across one side of the board. The 0.1 inch
(2.54 mm) spacing allows sockets for ICs. The continuous tracks may be easily
and neatly cut as desired to form breaks between conductors using a 5 mm twist
drill, a hand cutter made for the purpose, or a knife.
Fig 6.2 Vero board
PRINTED CIRCUIT BOARD:
A printed circuit board (PCB) mechanically supports and electrically connects
electrical or electronic components using conductive tracks, pads and other
features etched from one or more sheet layers of copper laminated onto and/or
between sheet layers of a nonconductive substrate. Components are generally
soldered onto the PCB to both electrically connect and mechanically fasten
them to it.
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Fig 6.3 Printed circuit board
ASSIGNMENT
DEGISNING THE VIRTUAL PCB LAYOUT CIRCUIT:
PCB layout can be designed by using a PCB designing software like Proteus.
PROTEUS:
The Proteus Design Suite is a proprietary software tool suite used primarily for
electronic design automation.
There is a lot that goes into any engineered design, from a basic printed circuit to a
complex non rigid PCB. Any new electronic device will start as a block diagram
and/or a set of electronics schematics. Here's the full list of PCB layout and design
steps:
1.
2.
3.
4.
5.
6.
7.
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Project on Proteus
Selection of Components
Create the Schematic
Create a PCB Layout
Auto Routing
Printing Out Layers
3D Visualization
PROCEDURE
Step 1: Project on Proteus
Start by clicking on the new project.
A window will be opened where schematic sketch can be drawn.
Fig 6.4 Window of schematic capture
Step 2: Selection of Components
For designing the circuit open the PCB layout window that is Schematic
capture.
Choose the required components by selecting the P button.
After clicking it a new window will be appeared. By typing the name of
device or just selecting the category of the device, it will be appeared on list.
Fig 6.5
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Choosing
the components
Step 3: Create the Schematic
Whether generating a design from a template or creating a printed circuit board
from scratch, it is probably best to begin with the schematic. One’s schematic is
similar to the blueprints for its new device, and it is important to understand what
is shown in schematics. First, schematics show the following:
•
•
•
Which components are used in design
How components are connected together
The relationships between groups of components in different schematics
Fig 6.6 Selection of components
Select any component and then move the curser to the area
available for circuit designing.
Select any location for placing the component in the given area and
double click to place it.
Repeat the same step for placing the other components.
To change the value of any device like resistor or voltage source, select
the device and go the properties and value can be changed here.
After adjusting the components, they are connected through wires.
To run the circuit, PLAY button is pressed which is present on the most
bottom left on Proteus.
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Step
4 : Create a PCB Layout
As the voltage source
( VSINE) is used in the
be placed on PCB boa
rd. So, it is replaced by
drawn circuit but can’t
Double Pins
.
Fig 6.8 replacement of pins
Now it is ready for PCB designing.
PCB layout is selected.
Fig 6.9 selecting PBC layout
After clicking on the Square button, Board Edge is
bottom tool bar.
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Fig 6.10 selecting board edge
selected from
Then in the blue region, a rectangle is
drawn of desired size of the PCB window.
Now Tool button is selected from the top
of PCB window. Click on auto placer. The
components will be placed in region bounded by
board edge.
Green and yellow lines will be seen.
Green ones indicate the connection of two
points while yellow ones indicates that terminal
of component is joined with other components.
Step
5 : Auto Routing
The entire board will then be routed according to a predefined sequence
and taking into account the configurable values
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The auto router button is selected at the top right of PCB window.
Fig 6.1 3 A uto rout ing
Step 6: Printing out layers:
Top layer of cooper can be printed out by selecting the top layer by
clicking output button and then selecting the pdf.
Fig 6.1 4 Printing top layer
Fig 6.1 5 Top copper
layer
Bottom layer
and top silk layer can also be printedlayer
out by same
procedure, this time by selecting the bottom layer
.
.And the silk layer.
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Fig 6.1
Step
6 Bottom
copper
layer
7 : 3 D Visualization
Fig 6.1
Fig 6.1
8 Front side
9 Back
side
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Top silk layer (right side
)
:
The 3D view of the PCB can
Fig 6.1
( left side)
be seen by clicking on the 3D visu
7 selecting 3D visualization button
a lizer .
Lab 7. PCB Layout printing using PCB Editor
PCB:
A printed circuit board (PCB) mechanically supports and electrically connects
electrical or electronic components using conductive tracks, pads and other features
etched from one or more sheet layers of copper laminated onto and/or between sheet
layers of a nonconductive substrate
PRINTING LAYOUT:
The component model used for PCB design is called “footprint”.
A PCB footprint is created by placing pads providing the connectivity (brown area)
and silkscreen used to identify the component shape and position (gray area).
Silkscreen is placed on a silkscreen layer.
For layout printing the ‘PRINT’ is selected from output option. A new window will be
opened. The option available there are mode, path, scale, rotation etc. Further there
are 4 modes

ART MODE:
Module design can be printed

SOLDER RESIST:
This is for prevention of short circuits. For this select mode as ‘solder resist’
and select ‘bottom resist’ and ‘board edge’. Also select reflection as
‘mirror’ mode.

SMT MASK

DRILL PLOT:
This layer is used to indicate the drill place and drill hole size.
Select ‘drill’ and ‘board edge’. Select ‘normal’ in Reflection option.
Here to print out the art mode is used.
Top copper layer:
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
This is printed for dual layered PCBs.
Fig 7.1 Top copper layer
Bottom copper layer:
To this layer click on ‘bottom copper’ and ‘board edge’ in
‘layer/artwork’.
Adjust the scale as 100%, select ‘X Horizontal’ in Rotation
and ‘Mirror’ in ‘reflection’ option.
The printed side will be of copper layer in the opposite
direction so we select the ‘mirror’ option.
Fig 7.2 Bottom copper layer
Top silk layer:

This is in combination with the bottom copper layer. Top silk
layer prints the components view.

For this, ‘top silk’ and ‘board edge’ will be chosen in
‘layer/artwork’.

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After that ‘normal’ in ‘Reflection’ mode will be chosen.
Fig 7.3 Top silk layer
Bottom silk layer:
This is printed for dual layered PCB.
Fig 7.4 layers of PCB
PROCEDURE FOR HOT IRONING METHOD
STEP 1: Take a printout of circuit board layout
•
•
You should take the mirror print out.
Select the output in black both from the PCB design software and the
printer driver settings.
•
Make sure that the printout is made on the glossy side of the paper.
Fig 7.5 Print out
STEP 2: Cut the Copper Plate for the Circuit Board
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Cut the copper board according to the size of the layout using a hacksaw or a cutter.
Fig 7.6 Copper clad plate
Now, the copper side of the PCB is rubbed using steel wool or abrasive sponge scrubs.
This removes the top oxide layer of copper as well as the photoresist layer. Sanded
surfaces also allow the image from the paper to stick better.
Fig 7.7 Rubbing away the top oxide layer
STEP 3: Transfer the PCB Print onto the Copper Plate
Method 1: Iron on Glossy Paper Method (For Complex Circuits)
Transfer the printed image (taken from a laser printer) from the photo paper to the
board. Make sure to flip top layer horizontally. Put the copper surface of the board on
the printed layout. Ensure that the board is aligned correctly along the borders of the
printed layout and use tape to hold the board and the printed paper in the correct
position.
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Fig 7.8 Placing of printed paper on copper sheet
Method 2: Circuit by Hand on PCB (For Simple and Small Circuits)
Using the circuit as a reference, draw a basic sketch on the copper plate with a pencil.
Once your sketch looks good, trace over it with a permanent black marker.
Fig 7.9 Using the permanent marker
STEP 4: Iron the Circuit from the Paper onto the PCB Plate
•
After printing on glossy paper, we iron it image side down to the copper
side, then heat up the electric iron to the maximum temperature.
•
Put the board and photo paper arrangement on a clean wooden table
(covered with a table cloth) with the back of the photo paper facing you.
•
Using pliers or a spatula, hold one end and keep it steady. Then put the
hot iron on the other end for about 10 seconds. Now, iron the photo paper all
along using the tip while applying a little pressure for about 5 to 15 mins.
•
Pay attention to the edges of the board – you need to apply pressure and
do the ironing slowly.
•
Doing a long hard press seems to work better than moving the iron
around.
•
The heat from the iron transfers the ink printed on the glossy paper to the
copper plate.
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Fig 7.10 Ironing the paper onto the plate
CAUTION: Do not directly touch copper plate, IT WILL BE VERY HOT FROM THE
IRON.
After ironing, place the printed plate lukewarm water for about 10 minutes. The paper will
dissolve, then you can remove the paper gently. Remove the paper by peeling it from a
low angle.
Fig 7.11 Peeling of paper
In some cases, when removing the paper, some of the tracks get fainted. In the figure
below, you can see that the track is light in color, hence we can use a black marker to
darken it as shown.
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Fig 7.12 light trace
Fig 7.13 dark trace
STEP 5: Etch the Plate
You need to be really careful while performing this step.
•
•
First, put on rubber or plastic gloves.
Place some newspaper on the bottom so the etching solution does not
spoil your floor.
•
Take a plastic box and fill it up with some water.
•
Dissolve 2-3 teaspoons of ferric chloride power in the water.
•
Dip the PCB into the etching solution (Ferric chloride solution, FeCl3) for
approximately 30 mins.
•
The FeCl3 reacts with the unmasked copper and removes the unwanted
copper from the PCB.
•
This process is called Etching. Use pliers to take out the PCB and check if
the entire unmasked area has been etched or not. In case it is not etched, leave
it in the solution for some more time.
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Fig 7.14 Etched copper plate
STEP 6: Cleaning, Disposal, and the Final Touches for the Circuit
Board
Be careful while disposing of the etching solution, it’s toxic to fish and other water-based
organisms! Don’t even think about pouring it in the sink when you are done, it is
ILLEGAL and might damage your pipes. Instead, dilute the etching solution and then
throw it away somewhere safe.
A few drops of thinner (nail polish remover works well) on a pinch of cotton wool will
remove completely the toner/ink on the plate, exposing the copper surface. Rinse
carefully and dry with a clean cloth or kitchen paper. Trim to final size and smoothen
edges with sandpaper.
Fig 7.15 Removing the ink
Now, drill holes using a PCB driller like this PCB driller and solder all your cool
components to the board. If you want that traditional green PCB look, apply solder
resistant paint on top PCB lacquer.
PROCEDURE FOR THE COLD METHOD
The PCB layout print can be transferred on copper sheet through cold method.
Designing of board on a PCB, it can be printed out (mirror image) on a paper
using a laser printer after measuring and cutting a copper clad according to
the size of circuit template.
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Fig 7. 16 removal of ink/ cleaning
Before transferring the toner it’s necessary to clean the surface of
copper clad.
Now take the printed paper and spray some spray. It contains alcohol
and some natural oil this spray reacts with the toner and makes it sticky for
a short amount of the time.
Fig 7.17 spray on paper
Paper is put on copper clad immediately after spray. Solution
Alcohol and acetone can also be used as a spray with ratio of 8:3. Let it dry for at
least 5 minutes then paper is removed very gently.
And will get a nicely printed board if it is bit wet then let it dry for another 5
minutes or if you feel that some parts are not printed then draw it with
permanent marker.
Fig 7.18 placing the paper
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Fig 7.19 removal of paper
PCB ETCHING:
A bowl is taken with some water in it.
Few drops (2-3 tea spoon) of ferric chloride solution are dissolved in it.
PCB is dipped and left in the etching solution for some time (30 minutes).
Fig 7.20 Etching
After that it is removed and is cleaned with thinner acetone nail polish remover or
simply by scrubbing.
Fig 7.21 cleaned copper plate
FINAL TOUCH:
Now it’s time to drill the holes.
It is quite possible that one won’t get the right size drill bit, so a needle can be
used to make holes.
At last, all the parts or components are assembled and soldered.
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Fig 7.19 Drilling
Fig 7.20 adjusting the components
Fig 7.21 Soldering the component
Lab NO 08;
TO KNOW ABOUT TOOLS ELECTRICAL MATERIAL, SYMBOLS, AND
DIVECES
BASIC INTRO:
Three-phase electric power is a common method of electric power
transmission. It is a type of polyphase system mainly used to power motors and many
other devices. A three-phase system uses less conductor material to transmit electric
power than equivalent single-phase, two-phase, or direct-current systems at the same
voltage.
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Most domestic loads are single phase. Generally, three phase power either does not
enter domestic houses at all, or where it does, it is split out at the main distribution
board. The single-phase AC supply is 230V but a threephase supply is 440V. 8.2
BASIC SAFETY RULES:
1. Inspect regularly
•
Regularly inspect your tools to make sure that they are in good
condition.
2. Wear gloves
•
Always wear appropriate personal protective equipment.
3. Carry with care
•
Never carry tools up a ladder.
•
If you need to take tools up to a height, use a bag or hoist them up
in a bucket.
4. Don't pocket sharp objects
•
Never carry sharp or pointed tools in your pocket.
them in a toolbox.
Instead, carry
5. Be aware of your surroundings
•
Always be aware of the people around you when using tools.
6. Use the right tools
•
Always use the right tools for the job.
•
Never use a tool for a different purpose than it was intended.
risk damaging the tools and injuring yourself.
You
7. Follow instructions
•
Only operate tools according to manufacturers' instructions.
8. Clean and return
•
After using a tool, clean it and return it to its proper storage place.
9. Oily hands are dangerous
•
71 | P a g e
Don't work with greasy or oily hands.
10.
•
Protect your eyes
Always wear eye protection.
TOOLS USED IN WIRING
PLIERS:
Pliers are made in various shapes and sizes and for many uses. Some are used
for gripping something round like a pipe or rod, some are used for twisting wires, and
others are designed to be used for a combination of tasks including cutting wire.
Fig 8.1 Plier
SCREW DRIVER:
Screwdriver, tool, usually hand-operated, for turning screws with slotted
heads. For screws with one straight diametral slot cut across the head, standard
screwdrivers with flat blade tips and in a variety of sizes are used.
Fig 8.2 Screw driver
HAMMER:
Hammers are used for general carpentry, framing, nail pulling, cabinet
making, assembling furniture, upholstering, finishing, riveting, bending or shaping
metal, striking masonry drill and steel chisels, and so on. Hammers are designed
according to the intended purpose.
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Fig 8.3 Hammer
LINE TESTER:
Line tester is a basic tool which is used to test and identify Phase / Live/ Hot or
Positive (+) wire / conductor in electrical installation also known as voltage or current
detector.
Fig 8.4 Line tester
MEASURING TAPE:
A tape measure or measuring tape is a flexible ruler used to measure size or
distance. It consists of a ribbon of cloth, plastic, fiber glass, or metal strip with linearmeasurement markings. It is a common measuring tool.
Fig 8.5 measuring tape
WIRES:
Electrical wires are conductors that transmit electricity from a source, usually a
nearby transformer. They also conduct electricity in appliances and electronic devices.
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Electrical wires come in various materials, casings and sizes. Although they can be
made from aluminum and other materials, almost all electrical wires are made of copper.
Fig 8.6 wires
TYPES OF CIRCUIT:
There are three types of circuits. They are:
Open circuit
Closed circuit
Short circuit
OPEN CIRCUIT:
An open circuit implies that the two terminals are points are externally
disconnected, which is equivalent to a resistance R=∞. This means that zero
current can flow between the two terminals, regardless of any voltage difference.
Fig 8.7
CLOSED CIRCUIT:
Closed circuit means a complete electrical connection around which current flows or
circulates.
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Fig 8.8
SHORT CIRCUIT:
An electrical circuit in a device of lower resistance than that of a normal
circuit, especially one resulting from the unintended contact of components
and consequent accidental diversion of the current.
Fig 8.9
ELECTRICAL CIRCUIT:
Electric circuit, path for transmitting electric current. An electric circuit includes a
device that gives energy to the charged particles constituting the current, such as a
battery or a generator; devices that use current, such as lamps, electric motors, or
computers; and the connecting wires or transmission lines.
Fig 8.10
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TYPICAL LIGHTING CIRCUITS:
Lighting circuits are wired in two different ways, using either junction-boxes or loop-in
ceiling roses. The loop-in system predominates - though individual circuits often
combine the two for the most economical use of cable.
Unlike power circuits, lighting circuits are always of the radial type. The cable leaves the
consumer unit and runs to each outlet position before terminating at the last fitting on
the line. Most houses have at least two lighting circuits - usually one upstairs and one
down.
Fig 8.11
8.6 WIRING
WIRING METHODS:
Wiring is a process of connecting various accessories for distribution of electrical
energy from supplier's meter board to home appliances such
as lamps, fans and other domestic appliances is known as Electrical Wiring.
The description of three different electrical circuits is as follows:
PARALLEL CIRCUIT:
A parallel circuit comprises branches so that the current divides and only part of it
flows through any branch. The voltage, or potential difference, across each branch of a
parallel circuit is the same, but the currents may vary.
Fig 8.12
SERIES CIRCUIT:
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A series circuit comprises a path along which the whole current flows
through each component.
Fig 8.13
SERIES & PARALLEL COMBINATION:
The circuit is series nor parallel is series-parallel circuit. As the circuit is
combination of series and parallel, the current, voltage, resistance and power
cannot be determined by simple ohm’s law. Different theorems like Norton’s,
Thevenin’s, maximum power transfer theorem are applied or will simplify the
circuit in basic series and parallel circuits to find all those quantities.
Fig 8.14
Lab 9. Introduction to Wires and Cables
INTRODUCTION
Electrical cable and wires are considered as a same thing. In fact they are quite different.
A wire is made of a single electrical conductor while a cable is a group or bundle of
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multiple wires inside a common sheathing. Both of them are used for carrying electrical
current.
Nowadays due to the advancement in technology, almost everything is powered by
electricity. Be it indoor or outdoor, we need supply of smooth, uninterrupted electricity
which is achieved by using suitable type of wires and cables. Not only the electrical sector
uses cables and wires for power transmission and distribution to our house and
industries, the Telecom sector also relies on various types of cables for uninterrupted
data transmission.
Wire
A wire is a single usually cylindrical, flexible strand or rod of metal. Wires are used to
bear mechanical loads or electricity and telecommunications signals.
Single Conductor wire is the most popular choice for electrical layout inside a home. It is
available in multiple gauges, color (for phase, neutral and ground identification) and solid
or stranded conductors. A single solid wire provides better connections but single
stranded wires are easier to route through conduits. Both of them are available in THW
and THHN insulation.
Figure 31: wire
Advantages of Wire
Using solid wire is perfect in case of higher frequencies and it offers low resistance and
cost. And the standard wire shows high resistance to the metal.
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cable
An electrical cable is an assembly of one or more wires running side by side or bundled,
which is used to carry electric current.
Figure 32:Electrical cable diagram
Advantages of Cable
Cables are heavy duty, well insulated and have higher strength.
Rules that apply to both
1.
Damaged or torn wires or cables must be replaced.
2.
Assure that all the cables and wires are polarized and have safety closures.
3.
Keep the wires and cables out of reach of children.
4.
Avoid placing wires and cables where they can easily be a trip hazard.
Labeling of Cables
The labeling of the cables is very important and it provides a lot of information regarding
its insulation types, numbers of wires and the gauge of the wires. Take a look at some of
labels written on the wires commonly used in home wiring.
1.
14-2G: The cable contains two insulated wires and a ground wire; individual
wire is 14-gauge.
2.
14-3G: The cable contains three insulated wires and a ground wire;
individual wires are 14gauge.
3.
12-2 w/G: The cable contains two insulated wires with a ground wire;
individual wires are 12gauge.
4.
12-3 w/G: The cable contains three insulated wires with a ground wire;
individual wires are 12-gauge.
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5.
600 V: This Cable is rated for a maximum of 600 volts; commonly used NM
cable for home wiring.
6.
TYPE NM-B: NM stands for Non-metallic, it is a non-metallic sheathed
cable of type-B; this is the commonly used cable for wiring appliances and devices
in home.
The most important label of them is about the insulation or the plastic coating around the
conducting wires. Here are some of the common labels written on wires.
1.
THHN
2.
THWN
3.
THW
4.
XHHN
The meaning of each letter used in the labels above is given below:
•
T: Thermoplastic insulation, a fire-resistant material
•
H: Heat-resistant; able to withstand temperatures up to 167 F.
•
HH: Highly heat-resistant; able to withstand temperatures up to 194 F.
•
W: “Wet,” or approved for damp and wet locations; this wire is also suitable
for dry locations
•
X: Insulation made of a synthetic polymer that is flame-retardant
•
N: Nylon-coated for resistance to oil and gasoline
Residential Wiring Cables
The residential wiring from the utility pole to the appliances or devices inside the
home is divided into mainly five types.
Service Drop Cable:
It is the cable between the utility pole and the consumer’s premises or building.
The service drop cable is an overhead electrical line from the pole to the service
weatherhead of a house.
The service drop cable can be of many types given below:
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Main Feeder Wires:
The main feeder cables & wires supply the power from the service weatherhead to the
building. The cables used for this purpose are 600v THHN, solid or stranded with the
rating of 25% more than the maximum required load.
Panel Feed Wires:
The panel feed wires supply power to the main distribution junction box. It is usually black
insulted THHN cables with rating of 25% more than maximum load current.
Non-Metallic Sheathed Wires:
The non-metallic or NM sheathed wires are used for in-house wiring. It may consist of 2
or more than 2 insulated conductors with an insulated or bare ground conductor. There
is another layer of plastic XLPE sheathing for more protection. The latest version NM
type-B is currently used by electricians for interior installation. The conductors could be
solid or stranded. The stranded conductors are easier to route through conduits.
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Single Conductor Wire
Single Conductor wire is the most popular choice for electrical layout inside a home. It is
available in multiple gauges, color (for phase, neutral and ground identification) and solid
or stranded conductors. A single solid wire provides better connections but single
stranded wires are easier to route through conduits. Both of them are available in THW
and THHN insulation. See Figure 33.
Types of Wire and Cable
The common types of cables and wires are illustrated below.
Types of Electrical Wires
1.
Solid – A solid wire has a single conductor and is either insulated or bare and it is
usually protected by a coloured sheath. This wire offers a lower resistance and is best to
use in higher frequencies.
2.
Standard – A standard wire contains many thin wire strands that are twisted
together. These wires are used where the flexibility is required, standard wire can be
used over a long period of time.
Comparatively, the standard wire has larger cross-sectional area than the solid wire.
Figure 33: Single Conductor wire
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Types of Electrical Cables
Twisted pair cable
A twisted pair cable includes 2 cables that are twisted together. This twisting can avoid
the noise produced by magnetic coupling and thus it is used to carry signals. Twisted pair
cable is generally used in data communication and telecommunication. Typically, are
used in Ethernet network and telephone communication.
Figure 34: twisted pair
They are further divided into two types based on their noise protection.
Unshielded Twisted Pair (UTP) Cable
The UTP cables do not have any extra shield for protection against noise. They twisted
pairs may reduce the noise but it still affects it. Various categories of UTP cables are
used in residential and commercial building with various bandwidth e.g. CAT1, CAT2 etc.
Figure 35:Unshielded Twisted Pair
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Shielded Twisted Pair (STP) Cable
The STP cable has an extra layer of foil that protects the wires from electromagnetic
interferences. They are used for high-end applications where the cables may get affected
by external environmental interferences.
Figure 36:Shielded Twisted Pair
Coaxial cable
A coaxial cable has an inner conductor which is surrounded by a parallel outer foil
conductor which is protected by insulating layers. In the cable, the 2 conductors are being
separated from each other by an insulating dielectric. These cables are generally used
in TV cable as its performance is more stable than the twisted pair cable.
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Figure 37: RG-6 Coaxial Cable
Fiber optic cable
The fiber optic cable transmits the signals through a bunch of glass threads and
comparatively, it has a greater bandwidth than metal conductors and that means they
can carry more information and data. For this reason, fiber optic cables are used instead
of traditional copper cables.
Figure 38: Fiber Optic Cable
The fiber optics cable is classified into two main types.
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Single Mode or Mono-mode Fiber Optics Cable
This cable allows only one mode of light to transmit. It is made of a very thin single strand
of fiber that allows only single light wave to propagate. This decreases the number of
light reflection which reduces the attenuation in signal. It provides high transmission rate
at long distance with very low attenuation but at high cost.
Multi-Mode Fiber Optics Cable
This type of fiber optic cable is made of relatively thicker fibers that allow more than one
light waves so it can transmit relatively more data. But the number of light reflections due
to large number of waves at large distance causes attenuation and distort the signal at
the receiving end. This is why it is used for relatively short distance transmission such as
LAN, security system etc.
Figure 39: Single and multi-core optic cables
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Multi-conductor cable
This cable has 2 or more than 2 conductors which are insulated and their purpose is to
protect the signal integrity. Both twisted pair cables and multi-conductor are known as
balanced line configuration cables.
Figure 40: Multi-Core Cable
Non-Metallic Sheathed Cable
The non-metallic or NM sheathed cable is a type of electrical cable whose outer sheath
is made of plastic that protect the inside conductors. It is commonly used for residential
electrical wiring.
There are two types of NM sheathed cable based on number of conductors.
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Metallic Sheathed Cable
Metallic sheathed cable, as the name suggest is a type of armored electrical cable with
a metallic protection over the insulated conductors. The conductors are separately
insulated with plastic layer which is surrounded by a metallic sheath for extra protection.
The metal sheath can be braided or twisted that surrounds individual or all conductors or
it could a solid pipe like structure.
What’s the basic difference between Wires and Cables?
Wires and cables are the terms that are frequently used in the electrical and
communication field. But, people tend to get confused about both the terms as they look
similar, but actually are quite different. And in this article, we will be giving you a brief
description of the difference between wires and cables.
List some of the basic differences between Wires and Cables
The basic key difference between wires and cables is that a wire is a single conductor
whereas a cable is a group of conductors. Although, these conductors are made of a
common material- copper or aluminium. Usually, the wires are bare and are twisted.
But, some of the wires are coated with thin PVC layer. And in case of cables, they run
parallelly and are twisted or bonded together to form a single case. For the safety
purpose, an inner and outer sheath is made.
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Wire
A wire is measured by diameter. According to the diameter of the wire, it will be
measured by a gauge number. The smaller the gauge number, the thicker the wire. The
perfect gauge that is used in residential applications is 10 & 20. But, do keep in mind
that big wires carry more current and can damage household appliances by burning the
fuse.
Cable
A cable contains a hot wire carrying the current, a neutral wire to complete the loop and
a grounding wire as well. A cable is classified by the total number of wires it is made up
of and their gauge.
Different uses of Wire and Cable
Use of Wire
A wire is used to carry electricity, to bear the mechanical loads, to transmit
telecommunication signals, for heating jewellery, clothing, automotive or any industrial
manufactured parts like pins, bulbs and needles.
Use of Cable
A cable is used for power transmission, for telecommunication signals or to carry
electricity.
Types of Wire and Cable
Types of Electrical Wires
1. Solid – A solid wire has a single conductor and is either insulated or bare and it is
usually protected by a coloured sheath. This wire offers a lower resistance and is best
to use in higher frequencies.
2. Standard – A standard wire contains many thin wire strands that are twisted
together. These wires are used where the flexibility is required, standard wire can be
used over a long period of time. Comparatively, the standard wire has larger crosssectional area than the solid wire.
Types of Electrical Cables
1. Twisted pair cable – A twisted pair cable includes 2 cables that are twisted together.
This twisting can avoid the noise produced by magnetic coupling and thus it is used to
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carry signals. Twisted pair cable is generally used in data communication and
telecommunication.
2. Multi-conductor cable – This cable has 2 or more than 2 conductors which are
insulated and their purpose is to protect the signal integrity. Both twisted pair cables and
multi-conductor are known as balanced line configuration cables.
3. Coaxial cable – A coaxial cable has an inner conductor which is surrounded by a
parallel outer foil conductor which is protected by insulating layers. In the cable, the 2
conductors are being separated from each other by an insulating dielectric. These
cables are generally used in TV cable as its performance is more stable than the twisted
pair cable.
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4. Fibre optic cable – The fibre optic cable transmits the signals through a bunch of
glass threads and comparatively, it has a greater bandwidth than metal conductors and
that means they can carry more information and data. For this reason, fibre optic cables
are used instead of traditional copper cables.
Different advantages of using Wire and Cable
Advantages of Wire
Using solid wire is perfect in case of higher frequencies and it offers low resistance and
cost. And the standard wire shows high resistance to the metal.
Advantages of Cable
Cables are heavy duty, well insulated and have higher strength.
Rules that apply to both:
1. Damaged or torn wires or cables must be replaced.
2. Assure that all the cables and wires are polarised and have safety closures.
3. Keep the wires and cables out of reach of children, or for the safety of your kids
switch to Finolex flame retardant cables.
4. Avoid placing wires and cables where they can easily be a trip hazard.
Lab 10. Introduction to Magnetic Contactor & Different Actuators
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Contactor
Introduction
A contactor is an electrical device which is used for switching an electrical circuit on or
off. It is considered to be a special type of relay. However, the basic difference between
the relay and contactor is that the contactor is used in applications with higher current
carrying capacity, whereas the relay is used for lower current applications. Contactors
can be field mounted easily and are compact in size. Generally, these electrical devices
feature multiple contacts. These contacts are in most cases normally open and provide
operating power to the load when the contactor coil is energized. Contactors are most
commonly used for controlling electric motors.
Figure 41: Contactor
Contactor Components
The following three are crucial components of the contactor:
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Coil or Electromagnet
This is the most crucial component of a contactor. The driving force that is required to
close the contacts is provided by the coil or electromagnet of the contactor. The coil or
electromagnet and contacts are protected by an enclosure.
Enclosure
Just like the enclosures used in any other application, contactors also feature an
enclosure, which provides insulation and protection from personnel touching the
contacts. The protective enclosure is made from different materials, such as
polycarbonate, polyester, Nylon 6, Bakelite, thermosetting plastics, and others.
Generally, the open-frame contactor features an additional enclosure, which protects
the device from bad weather, hazards of explosion, dust, and oil.
Contacts
This is yet another important component of this electrical device. The current carrying
task of the contactor is done by the contacts. There are different types of contacts in a
contactor namely, contact springs, auxiliary contacts, and power contacts. Each type of
contact has an individual role to play.
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Figure 42:Contactor Components
Different Types of Contactor Devices
Knife Blade Switch
The knife blade switch was used earlier in the late 1800’s. It was probably the first ever
contactor that was used to control (start or stop) electric motors. The switch consisted
of a metal strip, which would drop onto a contact. This switch had a lever for pulling the
switch down or pushing it up. Back then, one had to level the knife blade switch into the
closed position by standing next to it.
However, there was a problem with this method of switching. This method caused the
contacts to wear out quickly, since it was difficult to manually open and close the switch
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fast enough to avoid arcing. As a result of this, the soft copper switches underwent
corrosion, which further made them vulnerable to moisture and dirt. Over the years, the
size of the motors increased which further created the need for larger currents to
operate them. This created potential physical danger to operate such high current
carrying switches, thus leading to a serious safety concern. In spite of doing several
mechanical improvements, the knife blade switch couldn’t be fully developed due to the
pertaining problems and risks of dangerous operation and short life of the contacts.
Figure 43:Knife Blade Switch
Manual Controller
Since the knife blade switch became potentially dangerous to use, engineers came up
with another contactor device, which offered a number of features that were missing in
the knife blade switch. This device was referred to as a manual controller. These
features included:
•
Safe to operate
•
Non-exposed unit, which is properly encased
•
Physically smaller size
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•
Single break contacts replaced with double break contacts
As their name implies, double break contacts can open the circuit in two places at the
same time. Thus, even in smaller space, it allows you to work with more current. Double
break contacts divide the connection in such a way that it forms two sets of contacts.
The switch or button of the manual controller is not operated remotely and is attached
to the controller physically.
The power circuit is engaged once the manual controller is activated by an operator.
Once activated, it carries the electricity to the load. Soon, manual contactors replaced
knife blade switches completely, and even today different variations of these types of
contactors are being used.
Figure 44:manual controller
contactor
Magnetic Contactor
The magnetic contactor does not require human intervention and operates
electromechanically. This is one of the most advanced designs of a contactor, which
can be operated remotely. Thus, it helps eliminate the risks involved in operating it
manually and putting operating personnel in potential danger. Only a small amount of
control current is required by the magnetic contactor to open or close the circuit. This
is the most common type of contactor used in industrial control applications.
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Figure 45:Magnetic Contactor
Actuators
An actuator is a part of a device or machine that helps it to achieve physical movements
by converting energy, often electrical, air, or hydraulic, into mechanical force. Simply,
An actuator is a component of a machine that is responsible for moving and controlling
a mechanism or system, for example by opening a valve.
Actuators - Components
An actuator requires a control signal and a source of energy. The control signal is
relatively low energy and may be electric voltage or current, pneumatic, or hydraulic
fluid pressure, or even human power. Its main energy source may be an electric current,
hydraulic pressure, or pneumatic pressure. When it receives a control signal, an
actuator responds by converting the source's energy into mechanical motion. In the
electric, hydraulic, and pneumatic sense, it is a form of automation or automatic control.
Main types of actuators
•
•
•
Hydraulics
Pneumatics
Electric Motors
Hydraulics
The hydraulic actuator consists of cylinder or fluid motor that uses hydraulic power to
facilitate mechanical operation. The mechanical motion gives an output in terms of
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linear, rotatory or oscillatory motion. As liquids are nearly impossible to compress, a
hydraulic actuator can exert a large force. The drawback of this approach is its limited
acceleration.
The hydraulic cylinder consists of a hollow cylindrical tube along which a piston can
slide. The term single acting is used when the fluid pressure is applied to just one side
of the piston. The piston can move in only one direction, a spring being frequently used
to give the piston a return stroke. The term double acting is used when pressure is
applied on each side of the piston; any difference in force between the two sides of the
piston moves the piston to one side or the other.
Figure 46: Hydraulic Actuator
Pneumatic
Pneumatic actuators enable considerable forces to be produced from relatively small
pressure changes. Pneumatic energy is desirable for main engine controls because it
can quickly respond in starting and stopping as the power source does not need to be
stored in reserve for operation. Moreover, pneumatic actuators are cheaper, and often
more powerful than other actuators. These forces are often used with valves to move
diaphragms to affect the flow of air through the valve.
The advantage of pneumatic actuators consists exactly in the high level of force
available in a relatively small volume. While the main drawback of the technology
consists in the need for a compressed air network composed of several components
such as compressors, reservoirs, filters, dryers, air treatment subsystems, valves,
tubes, etc. which makes the technology energy inefficient with energy losses that can
sum up to 95%.
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Figure 47: Pneumatic Actuator
Electric Actuators
An electric actuator is a device that can create movement of a load, or an action
requiring a force such as clamping, using an electric motor to create the necessary
force.
Figure 48: Electric Actuators
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Assignment;
Uses of contactors;
Contactor Applications
Three-phase applications call for contactors, while relays should be reserved for single
phase. This is because a relay only has a common contact, connecting to a neutral
position. Conversely, a contactor joins two poles without a common circuit between
them. While relays are fine in situations up to 250 volts AC, contactors are good for
situations up to 1000 volts.
It’s also important to consider the function you’re asking the component to serve in your
system. Contactors excel in situations in which an overload could happen and failure to
de-energize the circuit will put people and/or the system itself in danger. Relays are
incapable of providing this protection. However, for low-power applications where a
contactor added margin of safety isn’t warranted, specifying relays will reduce costs.
Thus, contactors are typically used to switch high-current motors, capacitors and
slighting systems. Contactors can also be fitted with auxiliary contacts to give them the
capability of operating in a normally closed condition. In this configuration, switching can
occur regardless of whether the contactor’s coils are energized or de-energized.
The Life Expectancy of a Contactor or Contact Life
The life expectancy of a contactor or its “contact life” is one of the biggest concerns of a
user. It is natural that the contacts are being opened and closed more frequently, the life
of the contactor will decrease. The opening and closing of the contacts create an
electric arc, which generates additional heat. The continued production of these arcs
can damage the contact surface.
Furthermore, the electrical arcs cause pitting and burn marks, which eventually blacken
the contacts. However, the black deposit or oxide on the contacts make them even
more capable of conducting electricity efficiently. Nevertheless, when the contacts get
worn out and corroded to a large extent, then it is necessary to replace them.
Thus, the faster the contact closes, the quicker the arc extinguishes. This in turn helps
to increase the life of the contact. The latest contactor versions are designed in such a
way that they close very quickly and energetically. This causes them to slam against
each other and produce a bouncing action as they rebound. This action is known as
contact bounce. The contact bounce phenomenon creates a secondary arc. It is not
only important to close the contacts quickly, but also to reduce the contact bouncing.
This helps reduce wear and secondary arcing.
NEMA vs IEC
There are two standards for contactors: .
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NEMA (National Electrical Manufacturers Association)
NEMA is the largest trade association of electrical equipment manufacturers in the
United States. NEMA encouraged manufacturers to standardize on frame sizes to allow
users to confidently specify, purchase, and install electrical components from different
manufacturers without a lot of hassle and cross-referencing. NEMA contactors also are
designed with safety factors that go beyond design ratings (oversized), up to as much
as 25%. NEMA is primarily a North American Standard.
NEMA contactors for low-voltage motors (less than 1,000 volts) are rated according to
NEMA size, which gives a maximum continuous current rating and a rating by
horsepower for attached induction motors. NEMA standard contactor sizes are
designated 00, 0, 1, 2, 3 to 9.
IEC (International Electrotechnical Commission)
IEC is a global standard. IEC contactors are not oversized. They are smaller than
NEMA contactors and less expensive. The range of sizes offered by manufacturers is
more numerous than the ten NEMA standards. As such, they are more specific to a
given application and are specified when the operating conditions are well understood.
Whereas, NEMA may be chosen when operating conditions, such as load are not well
defined.
IEC contactors are also “finger safe.” Whereas NEMA requires safety covers on
contactor terminals. Another key difference is IEC contactors react faster to overloads,
NEMA contactors are better at withstanding short circuits.
People often mistakenly perceive NEMA contactors as more robust. In reality, this is
due to their design being oversized.
The two tables below detail how NEMA and IEC size contactors and starters.
Applications
Lighting Control
Contactors are often used to provide central control of large lighting installations, such
as an office building or retail building. To reduce power consumption in the contactor
coils, latching contactors are used, which have two operating coils. One coil,
momentarily energized, closes the power circuit contacts, which are then mechanically
held closed; the second coil opens the contacts.
Electric Motor Starter
Contactors can be used as a magnetic starter. A magnetic starter is a device designed
to provide power to electric motors. It includes a contactor as an essential component,
while also providing power-cutoff, under-voltage, and overload protection.
Uses of actuators;
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APPLICATIONS:
Machine tools
• Loading & unloading of parts • Tool exchange operation • The positioning of the
machining tools • Measuring operations • Operations of the doors, hatches, and other
safety features
Factory automation • Automated & robotic welding • Injection Moulding • Servo presses
• Packaging machines • Robotic joining & clinching • Measuring, supervision, &
assembly
Materials handling • Forklifts & mobile lifting aids • Car chassis transportation • Food
container palletizing • Assembly line engine handling • Aircraft wing handling
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Lab 11. To prepare wiring for a fluorescent tube light with switch
control.
Tools Required
1. Screw driver
2. Hammer
3. Pliers
4. Line tester
Components Required
1. Switch
2. Tube light with fitting
3. Joint clips
4. Wires
5. Screws
6. Switch board
Working of the Fluorescent Tube Light
The fluorescent lamp circuit consists of a choke, a starter, a fluorescent tube and a
frame. The length of the commonly used fluorescent tube is 100 cm; its power rating is
40 W and 230V. The tube is filled with argon and a drop of mercury. When the supply
is switched on, the current heats the filaments and initiates emission of electrons. After
one or two seconds, the starter circuit opens and makes the choke to induce a
momentary high voltage surge across the two filaments. Ionization takes place through
argon and produces bright light.
Procedure
a. Mark the switch and tube light location points and draw lines for wiring on
the wooden board.
b. Place wires along the lines and fix them with the help of clips.
c. Fix the switch and tube light fitting in the marked positions.
d. Complete the wiring as per the wiring diagram.
e. Test the working of the tube light by giving electric supply to the Circuit.
Circuit Diagram
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Result
The wiring for the tube light is completed and tested.
Tube Light Connection Circuit & Wiring Diagram
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Required Wiring Components
A tube light is not connected in the supply main directly. Although it operates at 230 V,
50 Hz, some auxiliary electrical components are used to insert in this installation to
support the tube light operational principle. The total electrical components for single
tube light installation are
1. Choke: it is electromagnetic ballast or electronic ballast
2. Starter: Small neon glow up lamp
3. Switch
4. Wires
Please ensure that you take the appropriate electrical safety precautions when
performing any kind of electrical installation.
Wiring Diagram of Single Tube Light Installation with Electromagnetic Ballast
Different electrical symbols are used to make the wiring diagram below:
How to Install a Single Tube Light with Electromagnetic Ballast




From the junction box the neutral wire is not taken out to the switch board, rather
it is taken out from the junction box and carried out to the port 2 of the tube light,
as per figure above. A wire already connects port 2 and pin 1 of the terminal 2.
So the neutral wire is continued from port 2 to pin 1 of terminal 2.
The live wire or phase is taken from the junction box to the switchboard. The live
wire is connected to the one terminal of the switch. From another terminal of the
switch the wire is carried out up to tube light set up and connected to port 1.
One terminal of choke or ballast is connected to port 1 and another terminal is
connected to pin 1 of terminal 1.
One end of a starter is connected to pin 2 of terminal 1 and another end of the
starter is connected to the pin 2 of terminal 2.
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Wiring Diagram of Single Tube Light Installation with Electronic Ballast
How to Install a Single TubeLight with Electromagnetic Ballast

As no starter is used in the case of electronic ballast application, the wiring
diagram is slightly different.
 Electronic ballast has six ports, two ports out of six ports are for the input, and
the remaining four ports are for output ports. Suppose they are named port 1 and
port 2 for input; port 3, port 4, port 5 and port 6 are for output of the ballast.
 From the junction box the neutral wire is taken out and carried to port 2 of the
electronic ballast to connect, as per figure above.
 The live wire or phase is taken from the junction box to the switch board. The live
wire is connected to one terminal of the switch. From another terminal of the
switch, the wire is carried up to tube light set up and connected to port 1 of the
electronic ballast.
 Let, the color of wires from port 3 and port 4 are black, and from port 5 and port 6
are red or any other color.
 Port 3 and pin 2 of terminal 1 and Port 4 and pin 1 of terminal 1 are connected.
 Port 6 and pin 2 of terminal 2 and Port 5 and pin 1 of terminal 2 are connected.
[NB: The incoming voltage of port 1 and port 2 of the electronic ballast is only 230 V, 50
Hz. But output ports 3, 4, 5 and 6 give a very high voltage at the time of switch ON, may
be 1000 V at 40 kHz or more. When tube light starts to operate, output ports voltages
become below 230 V at 40 kHz or more.]
Lab 12. To wire for a stair case arrangement using a two-way switch.
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Tools Required
7. Screw driver
2. Hammer
Components Required
1. Two-way switches 2. Bulb holders
4. Joint clips
5. Wires
7. Ceiling rose and
8. Switch board
3. Pliers
4.
tester
Line
3. Bulbs
6. Screws
Procedure
1.
Mark switch and bulb location points and draw lines for wiring on the
wooden Board.
2.
Place wires along the lines and fix them with the help of clips.
3.
Fix the two-way switches and bulb holder in the marked position on the
wooden Board.
4.
Complete the wiring as per the wiring diagram.
5.
Test the working of the bulbs by giving electric supply to the circuit.
12.4 Theory
A two switch is installed near the first step of the stairs. The other two way switch is
installed at the upper part where the stair ends. The light point is provided between first
and last stair at an adequate location and height if the lower switch switches on the
light. The switch at the top or vice versa can switch it off. Two number of two way
switches are used for the purpose. The supply is given to the switch at the short
circuited terminals. The connection to the light point is taken from the similar short
circuited terminal of the second switch; other two independent terminals of each circuit
are connected through cables.
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Circuit Diagram
Figure 49: Electrical Ciruit Diagram
Figure 50: Staircase Wiring Circuit Diagram
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Tabulation
Result
The staircase wiring is completed and tested.
Staircase Wiring circuit diagram & working
Staircase wiring is a common multi-way switching or two-way light switching
connection; one light two switches wiring. Here one lamp is controlled by two switches
from two different positions. That is to operate the load from separate positions such as
above or below the staircase, from inside or outside of a room, or as a two-way bed
switch, etc.
The Staircase wiring diagram in a Traveler system or common system method is
shown below,
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A Staircase wiring makes the feasibility for the user to turn ON and OFF the load from
two switches placed apart from each other.
Staircase wiring circuit arrangement
The first pole and second pole of the SPDT switch S1 is connected to the
corresponding first and the second pole of the SPDT switch S2. That is similar poles of
both two switches are connected to each other.
The phase of the supply line is connected to the common pole of a switch. And
the phase line to the load is taken from the common pole of the next switch. It makes
an arrangement that, to close the circuit both the switches should be in the same
position in order to make the two common poles in contact to achieve a closed
circuit. Changing the ON & OFF condition of a single switch can determine whether the
circuit is closed or open. Thus in staircase wiring, we can control the load from both
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positions. If a truth table is made for the above traveler system output, it will have a
result similar to an XNOR gate. That is the light ON’s when both the switches are in the
same position.
Similarly, if the connections between the switch s1 and s2 have interchanged, the load
will ON when the switches have opposite positions
components required
Component
specification
Quantity
MCB
250V, 50Hz, 5A
1
Switch
SPDT , 250V , 5A
2
Lamp
230V
1
Coast 3-way or California 3-way wiring system
Coast 3-way or California 3-way wiring and Carter wiring system are another
method of connection that can be used for staircase wiring or multiway switching.
In Coast 3-way or California 3-way wiring, the first pole of both switches has the phase
line. The common pole and second pole of the first switch are connected to the
corresponding poles of the second switch. Then the phase connection to the
load connects from the second pole. Thus the lamp L1 will ON if one switch is ON and
the other is OFF. While in the same switch position, the lamp will be OFF. Coast 3-way
or California 3-way circuit shows a Truth table output of an XOR gate, i.e. the output will
be high when both switches are in opposite states.
Carter wiring system: A prohibited Multiway switching
Carter wiring is a 3-way wiring or a multi-way wiring method used at the time of old K&T
(knob-and-tube) installations, which has been prohibited by the NEC (National Electrical
Code) since the early ’90s.
In Carter wiring, both phase and neutral lines are connected to the switch. One throw of
the two SPDT switches is connected to the phase line and the other throws in the
neutral line. The load or bulb is connected between the common poles of the two SPDT
switches.
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The light will be OFF when both switches are in the same position. That is, both of the
bulb terminals have either phase or neutral. When the switches are flipped to the
opposite direction the terminals get opposite polarity and the light turns ON.
Unlike another multi-way switching, the two-socket terminals will not have a fixed phase
and neutral points. It changes to either phase or neutral depending on the position of
the switch.
The Carter wiring connection is similar to the H-bridge arrangement used in DC circuits
which are used to alternate the polarity across the load.
When the switch position is flipped to phase at both the switches, even though the bulb
does not light the socket may be charged at both of its terminals. Thus in this wiring
system, we can’t even replace a bulb by just turn off the light. Because we can’t predict
whether the socket is de-energized or not. During maintenance complete isolation of the
supply line cannot be guaranteed by a switch off. Because we can’t make sure it is in a
neutral position at both poles. So we should have to either turn off the main switch or
use a tester to ensure an open terminal.
Due to safety issues and high risk of electric shock the Carter wiring is no longer
recommended.
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Lab 13. To prepare Ethernet Cable.
Tools Required
RJ-45 Crimping tool
Ethernet cable tester
Wire cutter
Components Require
RJ45 Connectors
Ethernet Cable
Theory
An Ethernet cable is a network cable used for high-speed
wired network connections between two devices. This
network cable is made of four-pair cable, which is consists
of twisted pair conductors. It is used for data transmission
at both ends of the cable, which is called RJ45 connector.
The Ethernet cables are categorized as Cat 5, Cat 5e, Cat
6, and UTP cable. Cat 5 cable can support a 10/100 Mbps
Ethernet network while Cat 5e and Cat 6 cable to support
Ethernet network running at 10/100/1000 Mbps.
Ethernet cables can be wired as straight through or
crossover. The straight through is the most common type
and is used to connect computers to hubs or switches.
Crossover Ethernet cable is more commonly used to
connect a computer to a computer and may be a little
harder to find since they aren’t used nearly as much as
straight through Ethernet cable.
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Wiring Standard
Straight Through Ethernet Cable
A straight through cable is a type of twisted pair cable that
is used in local area networks to connect a computer to a
network hub such as a router. This type of cable is also
sometimes called a patch cable and is an alternative to
wireless connections where one or more computers access
a router through a wireless signal. On a straight through
cable, the wired pins match. Straight through cable use one
wiring standard: both ends use T568A wiring standard or
both ends use T568B wiring standard. The following figure
shows a straight through cable of which both ends are
wired as the T568B standard.
Figure 51: straight through connection
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Figure 52: Straight Through Ethernet Cable
Crossover Ethernet Cable
A crossover Ethernet cable is a type of Ethernet cable used
to connect computing devices together directly. Unlike
straight through cable, the RJ45 crossover cable uses two
different wiring standards: one end uses the T568A wiring
standard, and the other end uses the T568B wiring
standard. The internal wiring of Ethernet crossover cables
reverses the transmit and receive signals. It is most often
used to connect two devices of the same type: e.g. two
computers (via network interface controller) or two switches
to each other.
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Figure 53: Cross over connection
Figure 54: Crossover Ethernet Cable
Which to choose
Straight through vs crossover cable, which one should I
choose? Usually, straight through cables are primarily used
for connecting unlike devices. And crossover cables are
used for connecting alike devices.
Use straight through Ethernet cable for the following
cabling:
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•
Switch to router
•
Switch to PC or server
•
Hub to PC or server
Use crossover cables for the following cabling:
•
Switch to switch
•
Switch to hub
•
Hub to hub
•
Router to router
•
Router Ethernet port to PC NIC
•
PC to PC
Figure 55: Straight Through vs Crossover Cable
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Straight through and crossover cables are wired differently
from each other. One easy way to tell what you have is to
look at the order of the colored wires inside the RJ45
connector. If the order of the wires is the same on both
ends, then you have a straight through cable. If not, then
it’s most likely a crossover cable or was wired wrong. At
present, the straight through cable is much more popular
than crossover cable and is widely used by people.
Procedure
There are four pairs of wires in an Ethernet cable, and an
Ethernet connector has eight pin slots. Each pin is
identified by a number, starting from left to right, with the
clip facing away from you.
Figure56: RJ45 connector
1.
Cut into the plastic sheath about 1 inch (2.5 cm)
from the end of the cut cable. The crimping tool has a
razor blade that will do the trick with practice.
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Figure 57:
Step 1
2.
Unwind and pair the similar colors.
Figure 58:
Step 2
3.
Pinch the wires between your fingers and
straighten them out as shown. The color order is
important to get correct.
Figure 59:
Step 3
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4.
Use scissors to make a straight cut across the 8
wires to shorten them to 1/2 Inch (1.3 cm) from the cut
sleeve to the end of the wires.
Figure 60: Step 4
5.
Carefully push all 8 unstripped colored wires into
the connector. Note the position of the blue plastic sleeve.
Also note how the wires go all the way to the end.
Figure 61: Step5
6.
A view from the top. All the wires are all the way in.
There are no short wires.
Figure 62: Step6
WRONG WAY - Note how the blue plastic sleeve is not
inside the connector where it can be locked into place. The
wires are too long. The wires should extend only 1/2 inch
from the blue cut sleeve.
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Figure 63: Wrong Way to clip (1)
WRONG WAY - Note how the wires do not go all the way
to the end of the connector.
Figure 64:
Wrong way to clip (2)
7.
CRIMPING THE CABLE ... carefully place the
connector into the Ethernet Crimper and cinch down on
the handles tightly. The copper splicing tabs on the
connector will pierce into each of the eight wires. There is
also a locking tab that holds the blue plastic sleeve in
place for a tight compression fit. When you remove the
cable from the crimper, that end is ready to use.
Figure 65: Step
7
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8.
For a standard "Straight Through" cable, repeat all
steps and wire color order on the other end of cable. For a
cross-over cable, the other end will have a different color
order as shown by the crossover picture above.
Figure 66: Step
8
9.
Make sure to test the cables before installing them.
An inexpensive Ethernet cable tester does this quite well.
Figure 67: Step 9
Ethernet Cable Instructions:
•
Pull the cable off the reel to the desired length and
cut. If you are pulling cables through holes, its easier to
attach the RJ-45 plugs after the cable is pulled. The total
length of wire segments between a PC and a hub or
between two PC’s cannot exceed 100 Meters (328 feet).
•
Start on one end and strip the cable jacket off
(about 1″) using a stripper or a knife. Be extra careful not
to nick the wires, otherwise you will need to start over.
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•
Spread, untwist the pairs, and arrange the wires in
the order of the desired cable end. Flatten the end
between your thumb and forefinger. Trim the ends of the
wires so they are even with one another, leaving only 1/2″
in wire length. If it is longer than 1/2″ it will be out-of-spec
and susceptible to crosstalk. Flatten and insure there are
no spaces between wires.
•
Hold the RJ-45 plug with the clip facing down or
away from you. Push the wires firmly into the plug.
Inspect each wire is flat even at the front of the plug.
Check the order of the wires.
Double check again. Check that the jacket is fitted right
against the stop of the plug. Carefully hold the wire and
firmly crimp the RJ-45 with the crimper.
•
Check the color orientation, check that the crimped
connection is not about to come apart, and check to see if
the wires are flat against the front of the plug. If even one
of these are incorrect, you will have to start over. Test the
Ethernet cable.
Ethernet Cable Tips:
•
A straight-thru cable has identical ends.
•
A crossover cable has different ends.
•
A straight-thru is used as a patch cord in Ethernet
connections.
•
A crossover is used to connect two Ethernet
devices without a hub or for connecting two hubs.
•
A crossover has one end with the Orange set of
wires switched with the Green set.
•
Odd numbered pins are always striped, even
numbered pins are always solid colored.
•
Looking at the RJ-45 with the clip facing away from
you, Brown is always on the right, and pin 1 is on the left.
•
No more than 1/2″ of the Ethernet cable should be
untwisted otherwise it will be susceptible to crosstalk.
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•
Do not deform, do not bend, do not stretch, do not
staple, do not run parallel with power cables, and do not
run Ethernet cables near noise inducing components.
Figure 68: Ethernet connection comparison
Assignment;
Ethernet Cables
An Ethernet cable is a common type of network cable used
with wired networks. Ethernet cables connect devices such as
PCs, routers, and switches within a local area network.
Ethernet Cables Basics:
The most common network cable is called Cat 5, Cat 5e, Cat 6, Cat 6a, Cat7 all have
different functions, so it is necessary to buy or select the right cable for the right
application.
These network cables are used to connect various network components through
switches and Ethernet routers to computers, servers, and other network devices – if
there is an Ethernet interface, they can be connected via using an Ethernet cable.
The Ethernet cables for connection in most office and home environments rely on the
twisted pair cable – Cat 5, Cat 6, and Cat 7 all used this format. By twisting the wires
together the currents flow will be a balance for example, in one wire the current moves
in one direction, and in the other wire, the current flows in the other direction, allowing
the entire external fields around the twisted pair to cancel off.
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Types of Ethernet Cables:
1: Coaxial Cabling
A coaxial cable has an internal conductor that runs down the middle of the cable. The
conductor is surrounded by a layer of insulation which is then surrounded by another
carrying conductor shield, which makes this type of cable resistant to external
obstruction. This type of cable comes in two types – thinnet and thicknet. Each type has
a maximum transmission speed of 10 Mbps. Coaxial cables were previously used in
computer networks, but are now replaced by twisted pair cables.




Sheath: This is the outer cover of the coaxial cable. It protects the cable from physical
damage.
Braided Shield: This shield protects signals from external interference and noise. This
shield is made of the same metal used to make the core.
Insulation: Insulation protects the core. It also lays the groundwork for separation from
the braided-shield. Since both the base and the covered shield use the same metal,
without this layer, they will come in contact and form a short circuit on the wire.
Conductor: The conductor carries electronic signals. On the basis of conductor coaxial
cable can be divided into two types; single-core coaxial cable and multi-core coaxial
cable.
A single-core coaxial cable uses a single central metal (usually copper) conductor,
while a multi-core coaxial cable uses multiple thin strands of metal wires. The following
image shows both types of cable.
2: Twisted-pair Cabling
The twisted-room has four pairs of wires. These wires are twisted almost to each other
to reduce crosstalk and external interference. This type of cabling is common in current
LANs.
Twisted pair cables can be used for telephone and network cables. It comes in two
versions: UTP (Unshielded Twisted-Pair) and STP (Shielded Twisted-Pair). The
difference between these is that the STP cable has an additional layer of protection to
protect the data from external interference.
Similarities and differences between STP and UTP cables

Both STP and UTP can transmit data over 10Mbps, 100Mbps, 1Gbps, and 10Gbps.
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




STP cables are more expensive than UTP cables because they contain more material.
Both cables use the same RJ-45 (registered slot) module connector.
STP provides more noise and EMI resistance than UTP cable.
The maximum length of the two cable segments is 100 meters or 328 feet.
The two cables can accommodate a maximum of 1,024 nodes per segment.
The following image shows both types of twisted-pair cable.
3: Fiber-optic Cabling
This type of cable uses optical fibers to transmit data in the form of a light signal. The
cables have fiberglass strands surrounded by cladding material.
The core is wrapped in cladding; The cladding is wrapped in a buffer, and the buffer is
wrapped in a jacket.
1.
2.
3.
4.
The key is to transmit information signals in the form of light.
The cladding reflects light back into the core.
The buffer prevents light from leaking.
This jacket protects the cable from physical damage.
Fiber optic cables are fully immune to EMI and RFI. This cable can transmit data over
long distances at maximum speed. It can transmit 40 km of data at 100Gbps.
Fiber optic cables use light to transmit data. It reflects light from one point to another.
There are two types of fiber optic cables based on how much light they transmit at a
given time; SMF to MMF.
This type of cable can support longer cable lengths than other cable types (a few miles).
The cable has no electromagnetic interference. As you can see, this cable method has
many advantages over other methods, but its main disadvantage is that it is more
expensive.
There are two types of fiber-optic cables:


Single-mode fiber (SMF) – uses only one light beam to transmit information. Used for
longer distances.
Multi-mode fiber (MMF) – uses multiple light beams to transmit data. Less expensive
than SMF.
Four types of connectors are commonly used:
1. ST (Straight-tip connector)
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2. SC (Subscriber Connector)
3. FC (Fiber Channel)
4. LC (Lucent Connector)
Categories for Ethernet cables
A variety of different cables are available for Ethernet and other telecommunications
and networking applications. These network cables that are described by their different
categories, e.g. Cat 5 cables, Cat-6 cables, etc, which are often recognized by the TIA
(Telecommunications Industries Association) and they are summarised below:





Cat-1: This is not recognized by the TIA/EIA. It is the form of wiring that is used for
standard telephone (POTS) wiring, or for ISDN.
Cat-2: This is not recognized by the TIA/EIA. It was the form of wiring that was used
for 4Mbit/s token ring networks.
Cat-3: This cable is defined in TIA/EIA-568-B. It is used for data networks employing
frequencies up to 16 MHz. It was popular for use with 10 Mbps Ethernet networks
(100Base-T), but has now been superseded by Cat-5 cable.
Cat-4: This cable is not recognized by the TIA/EIA. However, it can be used for
networks carrying frequencies up to 20 MHz. It was often used on 16Mbps token ring
networks.
Cat-5: This is not accepted by the TIA / PTA. It is a widely used network cable for
100Base-T and 1000Base-T networks and allows data transmission over Ethernet
at 100 Mbit/s and above (125 MHz for 1000Base-T). The Cat 5 cable replaced the Cat
3 version and became the standard for Ethernet cable for several years. Cat 5 cables
are now obsolete and are not recommended for new installations.
Cat 5 cable uses twisted pairs to prevent internal crosstalk, XT, and also crosstalk to
external wires, AXT. Although not standardized, the Cat 5 cable normally uses 1.5 – 2
twists per centimeter.
The Cat 5 cable uses a twisted pair to prevent internal crosstalk. Although not
standardized, Cat 5 cables are typically used every 1.5 to 2 twists per centimeter.

Cat-5e: This cable type is recognized by TIA / EIA and defined in TIA / EIA-568 and
was updated in 2001. This has slightly higher frequency specification, as it increases
the performance of the Cat-5 cable to 125 Mbps.
Cat-5e can be used for 100Base-T and 1000Base-t (Gigabit Ethernet). Cat 5e standard
for Cat 5 enhanced and it is a form of Cat 5 cable manufactured to higher specifications
although physically the same as Cat 5. It is tested to a higher specification to ensure it
can perform at the higher data speeds. The twisted pairs within the network cables tend
to have the same level of twisting as the Cat 5 cables.
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Cat-5e can be used with 100Base-T and 1000Base-t (Gigabit Ethernet). The Cat 5e
standard has been improved, it is a form of Cat 5 cable that is manufactured at a higher
performance than the Cat 5, and it is tested at higher specifications to make it more
capable of transmitting data.

Cat-6: This cable is defined in TIA / EIA-568-B, which greatly improves the
performance of Cat-6. During cat production, the 6 cables adhere more tightly than Cat
5 or Cat 5e, and they have an outer foil or braided shield. Shield protection protects the
twisted pair wires inside the Ethernet cable and helps prevent corrosion and noise
interference. Cat-6 cables can technically support speeds of up to 10 Gbps, but only up
to 55 meters.

Cat-6a: The “a” in Cat 6a stands for “Augmented” and the standard was revised in
2008. The Cat 6a cables are able to support twice the maximum bandwidth and are
capable of maintaining higher transmission speeds over longer network cable lengths.
Cat 6a cables are well protected as a whole, so it is possible to eliminate the repellent
path. However, this makes them less flexible than Cat 6 cables.
Cat-7: This is an informal number for ISO/IEC 11801 Class F cabling. It comprises
four individually shielded pairs inside an overall shield. It is aimed at applications where
transmission of frequencies up to 600 Mbps is required.
Cat-8: These cables are still under development, but will improve speed and overall
performance in the near future.


Limitations of Ethernet Cables
A single Ethernet cable has a maximum distance capacity, meaning the cable has an
upper limit as to how long it can be before there is a signal loss (called attenuation).
This problem results because the electrical resistance of a long cable aff ects
performance.
Both ends of the cable should be close enough to each other to receive signals
quickly, and far enough away from outside electrical interference to avoid
interruptions. However, this precaution doesn't limit the size of a network, because
hardware like routers or hubs can join multiple Ethernet cables together on the same
network. This distance between the two devices is called the network diameter.
The maximum length of a CAT5 cable, before attenuation occurs, is 100m (328ft).
CAT6 can go up to 700 feet. Ethernet cables can be longer but may suffer from signal
loss, especially if they pass near large electrical appliances.
A short cable may suffer from reflection. However, some people have reported no
problems with cable lengths as low as 4 inches.
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Different types of RJ-45 connectors serve different purposes. One type, designed for
use with stranded cables, is incompatible with solid cables. Other types of RJ-45
connectors may work with both stranded and solid cables.
What is difference between cat 5 and cat 6.
CAT5e vs. CAT6 Bandwidth
Both CAT5e and CAT6 can handle speeds of up to 1000 Mbps, or a Gigabit per second.
This is more than sufficient for the speed of by far the most internet connections. The
chance is small that you currently have an internet connection with which you can
achieve up to 500 Mbps speed.
The main difference between CAT5e and CAT6 cable lies within the bandwidth, the
cable can support for data transfer. CAT6 cables are designed for operating frequencies
up to 250 MHz, compared to 100 Mhz for CAT5e. This means that a CAT6 cable can
process more data at the same time. Think of it as the difference between a 2- and a 4lane highway. On both you can drive the same speed, but a 4-lane highway can handle
much more traffic at the same time.
CAT5e vs. CAT6 Speed
Because CAT6 cables perform up to 250 MHz which is more than twice that of CAT5e
cables (100 Mhz), they offer speeds up to 10GBASE-T or 10-Gigabit Ethernet, whereas
CAT5e cables can support up to 1GBASE-T or 1-Gigabit Ethernet.
CAT5e vs. CAT6 Crosstalk
CAT5e and CAT6 are both twisted pair cables. Both use copper wires, with typically 4
twisted pairs (8 wires) per cable. In the past, the 250 MHz performance provided by
CAT6 was often achieved by using a nylon spline in the wiring, which isolated each of
the four twisted pairs, making the cable rigid. Nowadays, CAT6 cables are more flexible,
using other methods to reduce noise.
Regardless of whether a spline is used, CAT6 features more stringent specifications for
crosstalk and system noise. Not only does CAT6 provide significantly lower interference
or Near-End Crosstalk (NEXT) in the transmission compared to CAT5e, it also improves
Equal-Level Far-End Crosstalk (ELFEXT), Return Loss (RL) and Insertion Loss (IL).
The result is less system noise, fewer errors and higher data transmission rates.
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CAT5e vs. CAT6 Maximum Length
Both CAT5e and CAT6 offer lengths of up to 100 m per network segment. The
maximum achievable speeds will never be met beyond this length. This can result in a
slow or failing connection, or even no connection at all. If it is required to cover
distances longer than 100 m, the signal can be amplified with repeaters or switches.
When used for 10GBASE-T, the maximum length of a CAT6 cable reduces to 55 m.
After this distance the rate drops to 1GBASE-T. To be able to run 10GBASE-T over the
full 100 m, it is advised to use CAT6A also called Augmented Category 6 cable.
CAT5e vs. CAT6 Visual Differences
Most of the times, the cable category is printed on the cable. If not, you won’t be able to
identify the cable category by colour or RJ45 connector, but CAT6 cables are often
thicker than CAT5e cables because it uses thicker copper wires.
CAT5e vs. CAT6 Cost
Multiple characteristics have an influence on the cost of Ethernet cables, the main
elements being length, quality, copper content and manufacturer. In general, you will
find that CAT6 cables are priced 10-20% above CAT5e cables.
Why they are used
Cat 5 Cable
Category 5 cable, aka Cat 5, is a twisted cable built for computer networks. Since 2001,
the most popular type of Cat 5 cable is the Cat 5e cable. It is a standard cable that
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provides performance for up to 100 MHz. Its other uses include carrying signals for
telephones and video.
Applications
The primary use of Cat 5 cables lies in structured cabling for computer networks like
Ethernet over twisted pair. This particular cable standard provides performance ranging
up to a 100 MHz and works for both High-Speed Ethernet (two wire pair) and Gigabit
Ethernet(four wire pairs). This means that you can use it for internet applications and
other household network functions too.
Cat 5e
The “e” in the Cat 5e cable stands for enhanced. Overall, there are no physical
differences that differentiate a Cat 5 from a Cat 5e, but the 5e Ethernet is developed
and tested under stricter standards so as to eliminate crosstalk, which is basically a
fancy word for interference between signals. Currently, this cable is the most common
type for Ethernet usage, particularly due to its low production costs and faster speeds
compared to the Cat 5.
When it comes to choosing a network cable for companies, IT managers and business
owners have usually preferred the use of Cat 5 cables. So the choice of cables has
been pretty standard over the years.
At this point, you might argue that there are many other options for cables, some being
better than Cat 5. While that is true, there is no guarantee that it fits the need for your
particular network.
Advantage: Cost
There is a clear advantage of using Cat 5 cables when you bring cost into the equation.
It has and remains one of the cheapest options for networking cables. Due to its
affordability, it is also used in cross-over cable jobs as well.
Advantage: Transfer Speeds
Cat 5 provides a substantially higher transfer speed for Ethernet connections. In
comparison to older and obsolete cabling, it can reach higher rates. Other capabilities
include having the ability to transfer four signals at once.
Advantage: Versatility
Perhaps the shining star for Cat 5 is its versatility. Two forms of cable are used. One
form is called a solid conductor, which is stiff and is used to join together wall sockets
with the central panel in your home or office. The solid conductor is the cheapest form
of Cat 5 available in the market. The other one, which is the standard conductor form, is
used to connect computers to the wall socket. This wiring is a lot more flexible. The
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versatility of this cable makes it an ideal choice for multiple applications in cabling/wiring
computer networks and telephones with several better wires on the market.
Disadvantage: Data Transfer
While the cable has several advantages, it also comes with its fair share of limitations
as well. The main disadvantage of using a Cat 5 cable is the amount of data being sent
to and from the cable. The cable is very limited on its top-end in terms of data transfer.
While the cable is good for setting up a network at home, it can only handle up 100
Mbps. Therefore, trying to use the cable to set up networks for corporate offices and
networks might not be that useful. The data streaming through the network would be
just too much for the cable.
Disadvantage: Interference
Another disadvantage Cat 5 brings with it is the issue of sensitivity to interference.
When faced with electrostatic disturbances from several handheld devices and other
devices, the effectiveness of the cable is reduced. Objects that project inductive
interference, such as phones, microwaves, television signals, computer signals, and
other frequencies can cause a lot of interference with Cat 5 transfer. Additionally, it can
also pick up interference from cables that it is joint together with. This is referred to
as cross-talk. Cross-talk can result in serious problems with transferring data and
signals. Moreover, cross-talk also reduces transfer speeds.
Cat 6 Cable
Commonly referred to as Cat 6, the Category 6 cable is another twisted pair cable used
in Ethernet and network applications. It is backward complete, meaning it can be joint
together with Cat 5/5e and Cat 3 cables as well.
Compared with Cat 5 and Cat 5e, these cables support higher bandwidths. However,
they are also more expensive. They are expensive because of their QA standardization
and are more tightly wound compared to their predecessors, and have an outfit of foil
and braided shielding. The shielding protects the twisted wires inside the Ethernet
cables, which helps to prevent crosstalk and noise interference from happening. These
cables can technically support speeds going up to 10 Gbps, but only to a length of 55
meters.
Compared to the Cat 5 model, the Cat 6 features stricter specifications with regards to
crosstalk and system noise. It specifies that performance of up to 250 MHz compared to
100 MHz for both Cat 5 and Cat 5e.
Cat 6a
The “a” in this design of cable stands for “augmented”. Compared with the regular Cat 6
cables, the Cat 6a model supports twice the maximum bandwidth, and they are also
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able to maintain higher transmission speeds over cable lengths that are longer. These
cables are always shielded and so is their shielding, which makes them ideal when
cross-talk occurs. They help to completely eliminate cross-talk, making the Cat 6 cable
a lot denser, and less flexible than the Cat 6 model.
The Category 6 cable helps to set a standard for Gigabit Ethernet. The Category 6
Ethernet is backward compatible with the Cat 3 and Cat 5/5e cables. This helps to
create a high-speed computer network for both homes (rarely) and for larger companies
as well. However, it only provides that level of performance if other components within
the network are compatible with gigabit speeds as well.
Advantage: Speed and Performance
One of the best things about this cable is the level of speed that it provides. The Cat 6
can handle speed performances for up to 250 MHz. This performance makes the device
possible to be used with a faster Ethernet network, which includes Gigabit Ethernet
connections and even 10 GB Ethernet too.
The introduction of this cable was done to complement Gigabit internet in particular
which includes a wider range of interface cards, patch panels, routers, switches, and
other components which make for a full gigabit network. Many IT professionals realize
that the Cat 6 cable provides a speedy network performance which delivers gigabit
speeds.
Advantage: Similar Structure with Cat 5 Cable
This advantage can be mixed with the versatility of Cat 6 cables as well. In terms of
structure, both Cat 5 and the Cat 5e are the same. The Cat 6, Cat 5, and Cat 5e cables
each have a combination of 8 wires twisted together to form four pairs. The only major
difference is that one pair of Cat 6 cable is kept away from any contact with others so
that it produces double the bandwidth of the Cat 5 and Cat 5e cable as well.
Advantage: Backward Compatible
The plug and port of the Cat 6 cable are the same as the Cat 5 and Cat 5e cable. This
means that it can be plugged into any particular port or connection that provides support
to both the cables. If, for example, you choose to use the Cat 5 port, it will not provide
the full speed that is able to handle. It will operate at the same speed you would expect
for a computer network cable. However, speed is still better.
Advantage: Upgradable
If you are looking to update your company’s network, then the Cat 6 cable is included as
a part of the upgrade. The Cat 6 cable will not be operated at full speed if other units
within the network do not support gigabit speeds. We will highly recommend small
businesses that are looking to improve network performance to shift towards installing
the Cat 6 cable since it is becoming the industry standard.
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Disadvantage: Expensive
Compared with the costs of the Cat 5e cable, Cat 6 is a lot more expensive. If the cable
is not showing substantial improvement in your network, it is best to not install it for your
company. In most cases, the Cat 5e is a sensible choice since it is more economical
while still providing good performance. The Cat 5e cable also comes in a variety of
different colors.
Disadvantage: Does Not Guarantee Full Speed
It is an error of judgment to believe that buying a Cat 6 cable will offer them higher
speeds of the gigabit network. In reality, the Cat 6 cables only yield the full speed if
each of the components in the network is operating at the gigabit speeds. If even one of
the components is not rated gigabit, then your network is going to operate at the speed
of the slowest device.
The average users might sometimes be persuaded to purchase the Cat 6 cable without
truly understanding the impact that it will have on their network. Therefore, a bit of
research before making the decision is recommended.
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