1. Stani Memorial College of Engineering And Technology, Phagi
Electrical Engineering
108 Electrical And Electronics Engineering Lab Manual
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LAB MANUAL
Subject Code: 108
ELECTRICAL AND ELECTRONICS ENGINEERING LAB
(I B. Tech I Semester All Branch)
Established in year 2000
DEPARTMENT OF ELECTRICAL ENGINEERING
STANI MEMORIAL COLLEGE OF ENGINEERING & TECHNOLOGY,
PHAGI, JAIPUR – 303005
Website: www.smcet.in
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108 ELECTRICAL AND ELECTRONICS LAB
SYLLABUS
1. Assemble house wiring including earthing for 1- phase energy meter, MCB,ceiling fan, tube
light, three pin socket and a lamp operated from two different positions. Basic functional
study of components used in house wiring.
2. .Prepare the connection of ceiling fan along with the regulator and vary the speed.
3. Prepare the connection of single phase induction motor through 1-Phase Auto- transformer
and vary the speed.
4. Prepare the connection of three phase squirrel cage induction motor through Phase Auto-
transformer and vary the speed.
5. Prepare the connection of Fluorescent Lamp, Sodium Vapour and Halogen Lamp and
measure voltage ,current and power in the ckt
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EXPERIMENT NO. 1
Aim: - Assemble house wiring including earthing for 1-phase energy meter, MCB, celling fan, tube
light, three pin socket, a lamp operated from two different position and Basic functional study of
component used in house wiring.
Apparatus Required: -
S.No. Name Rating Quantity
1 Lamp holder 6A, 250V. 1
2 Ceiling rose 5A, 250V. 2
3 Switches( one way) 5A, 250V. 4
4 Socket outlet 5A, 250V. 1
5 Lamp 100w/200w 1/1
6 MCB B16, 250V 1/1
7 Tube light 20 W/40 W 250V. 1
8 Connecting leads ------------ As per required
9 Screw drivers ------------ As per required
Theory:-
The connection diagram of one lamp, one tube light (connected through ceiling rose), one fan (which
is connected through ceiling rose) and switches in looping system in fig (1).
1. Element of a circuit: - Wire diagram can be intimidating at first, but with a basic
understanding of the symbols and language used, they become as valuable and as easy to use
as any tool in your toolbox.
2. Conductor: - These are usually cooper or aluminum wire, and in some cases it can even be
the frame on which the component are mounted.
3. Load: -The load is the components that do all the work, such as a washer motor, heating
element or light bulb
4. Series circuit:- The current that flow in a series circuit will pass through every component in
the circuit.if any component with in the circuit is open or blown , current will not able to
flow through that circuit polarities. The same voltage is applicable to all circuit component
connected in parallel.
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5. Ground connection:- This connection is very important . it’s usually made with a bare wire
attached to the cabinet to the appliance, which is in turn connected to earth with in the service
panel of our home through a grounded plug.
6. Electrical component:- All electrical circuit must have a load. Loads have many forms and
purposes. An electric dryer or stove uses a resister called a heating element to create heat.
Circuit Diagram:-
Figure
Precaution :-
1. Do not touch any live conductor.
2. Study the symbol of element very carefully.
Procedure:-
1. Make the connection as shown in fig (1).
2. Connect phase terminal at one terminal of switches after connecting MCB.
3. The second terminal of switch should be connected with one terminal of lamp holder, ceiling
rose and socket etc.
4. Connect neutral terminal at other terminal of lamp holder, ceiling rose and socket etc.
5. Connect fan, tube light etc. in ceiling terminals.
6. Turn ON MCB and check by which device is operating, mark it and observe table;
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Observation Table:-
Device Switch
Lamp(L1) S1
Tubelight/Ceiling Rose S2
Fan/Ceiling Rose S3
5Amp, 5-pin Socket S4
Calculations:-
Result:- we have successfully prepare the connection and studyof house wiring of the given object.
References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
Viva voice Question:-
Que. 1) Why devices are connected in parallel?
Que.2) What is need of earth wiring in house wiring?
Que.3) What is the difference between ground and earth?
Que.4) What do you mean by 1-unit of energy meter?
Que.5) What is the purpose of energy meter?
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EXPERIMENT NO. 2
Aim:- Prepare the connection of ceiling fan along with the regulator and vary the speed.
Apparatus Required:-
S. NO. Name Range/rating Type Quantity
1. Fan motor(stator/rotor) 60W, 0.6A,
350rpm
230±10% volt
1 phase Induction
motor
1
2. Capacitor 2.5 MFD±5%
440V AC50Hz,
Max temp 85
-- 1
3. Fan assembly(rod,
blades)
--- -- 1
4. Fan regulator (0-350)rpm Resistance/electroni
cs
1/1
5. Test lamp 200W -- 1
6. Different tools --- -- As per
requirement
7. Multi Meter Analog/digital -- 1
8. Volt meter (0-300)V Moving coil 1
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Theory:-
CEILING FAN-:
A ceiling fan is a propeller blade and having two or more blades, directly driven by an electric motor
and intended for use with free inlet &outlet. According to use of electric motor fans are two types-
DC Fan:-
DC fans use dc series motor and generally used where dc supply is easily available.
AC Fan:-
AC fans are most commonly used domestic devices, which are generally known.
Different Parts of Ceiling Fan-:
Fig (1) shows the construction diagram of ceiling fan. It is contains following parts-
Figure:- Parts of Ceiling fan
9. Ammeter (0-1)A Moving coil 1
10. Connecting leads --- -- As per
requirement
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Motor: The motor employed for ceiling fan is generally a single phase, permanent capacitor,split
phase and squirrel cage induction motor. The stator consist of two windings
(a) Starting windings
(b) Running windings
Capacitor: A paper capacitor is provided at the top of the body of the fan. The value of capacitor
depends upon the rating of the fan. The capacity of rating is vary from 2.5 MFD to 3.0 MFD.
Blades: The ceiling fan is fitted with 3 or 4 angular blades of steel sheets or aluminum sheets.
Aluminum blades are lighter and add efficiency of fan. The blades are fixed on the body of fan with
the help of two machines screw.
Canopy: It is the shape of cup which covers thehook and capacitor. It is held on the suspension rod
of the fan where it is screwed. Two canopies are used in each fan and are made of plastic.
A) One for covering hook.
B) Another for covering the capacitor.
Ball-Bearings: Ball-bearings are use for ensuring free moments of rotating parts. They are provided
between rotating and stationary parts. The fans may have single or double ball-bearing.the double
ball bearing are therefore a little costlier.the bearing are made of high quality steel and are regularly
greased so as to provide long life.
Speed Regulator: It is used to control the speed of the fan. They can either electrical or electronic
type.
In electrical type regulator type speed regulator, speed is control by inserting and removing the
resistance in series of fan .
In electronic type regulator , a tric is used to control the speed by varying input voltage.it used to
triggering .
PRINCIPAL OF WORKING:
AC fans has single phase induction motor, which comprises to distributed windings stator rotor
when current given to the motor, the magnetic field is set in the stator windings which experiences a
force in the rotor to move it right angle to the field at the blades attached with the rotor displace the
air.
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Speed control by regulators: As we know that there are two types of regulators. In the electrical
regulator we use many resistances in seriesand connected with fan in series. At the position 1 the
maximum resistances is connected in series, hence current of fan deceases so the speed reduces.
In electronic type regulators, a triac is used to control the speed by varyinginput voltage. Adiac is
used for triggering the triac.
Circuit Diagram:-
Figure
Precaution:-
1. Connection should be proper. Loose connection is not allowed.
2. Do not touch any live wire or part.
3. Before switch on the supply, the connection should be checked by lab assistant.
4. Do not damage the terminals of part or wire etc.
Procedure:-
A) For testing-
1. Connect different circuit.
2.Check condition obtain for each and record.
B) For speed-
1. Connect ceiling fan as shown fig.
2. By varying knob of regulator, check the speed by visualization.
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Observation Table:-
S.No. Regulator resister Speed(rpm)
1.
2.
3.
Result:- We have successfully prepare the connection of ceiling fan with construction and working
principal. Thus we have got the speed regulation at various regulator resister.
References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
Viva voice Question:-
Que .1) Name the motor of ceiling fan?
Que.2) What is the function of capacitor in ceiling fan?
Que .3) What is name of insulation of ceiling fan?
Que. 4) Winding are fitted on stator or rotor of ceiling fan ?
Que.5) What happens if capacitor terminal interchanged?
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EXPERIMENT NO. 3
Aim:- Prepare the connection of Single phase Induction motor through 1-phase Auto-transformer
and vary the speed.
Apparatus Required:-
S.No. Name Type Range /Rating Quantity
1 Single phase induction
Motor
Squirrel-cage 230V, 1 or 2HP, 1500 RPM
50Hz
1
2 Volt meter M I (0-600V)/(0-300V) 1/1
3 Ammeter M I 2A/5A 1/1
4 Auto transformer 1-phase 230V/(0-270V) 1
5 Tachometer Digital 0-2000rpm 1
6 Wattmeter Dynamometer 10/20A, 300/600V,
1800/2000W
2
Theory:-
An induction or asynchronous motor is a type of AC motor where power is supplied to the rotor by
means of electromagnetic induction. These motors are widely used in industrial drives, particularly
poly phase induction motors, because they are rugged and have no brushes. Single-phase versions
are used in small appliances. Their speed is determined by the frequency of the supply current, so
they are most widely used in constant-speed applications, although variable speed versions, using
variable frequency drives are becoming more common. The most common type is the squirrel cage
motor, and this term is sometimes used for induction motors generally.
Basic operation:
In Inductionmotor, the statoris powered with alternating current (poly phase in large machines) and
designed to create a rotating magnetic fieldwhich rotates in time with the AC oscillations. In an
induction motor the rotor rotates at a slower speed than the stator field. Therefore the magnetic field
through the rotor is changing (rotating). The rotor has windings in the form of closed loops of wire.
The rotating magnetic flux induces currents in the windings of the rotor as in a transformer.
According to Lenz's law the rotor windings will try to oppose the cause of production of induced
current in the rotor. The cause of induced current in the rotor is the rotating stator magnetic field, so
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to oppose this the rotor will startto rotate in the direction of the rotating stator magnetic field to make
the relative speed between rotor and rotating stator magnetic field zero, thus the motor will start.
For these currents to be induced, the speed of the physical rotor must be lower than that of the
stator's rotating magnetic field ( ), or the magnetic field would not be moving relative to the rotor
conductors and no currents would be induced. As the speed of the rotor drops below synchronous
speed, the rotation rate of the magnetic field in the rotor increases, inducing more current in the
windings and creating more torque. The ratio between the rotation rate of the magnetic field as seen
by the rotor (slip speed) and the rotation rate of the stator's rotating field is called "slip". Under load,
the speed drops and the slip increases enough to create sufficient torque to turn the load. For this
reason, induction motors are sometimes referred to as asynchronous motors. An induction motor can
be used as induction generator, or it can be unrolled to form the linear induction motor which can
directly generate linear motion.
Stator:
The stator is made of the several tin lamination of aluminium or cast iron.they are punched and
clamped together to form a hollow cylinder.coils of insulation wires are inserted in to these slots.
Each grouping of coils , together with the core it surround , forms an electromagnet on the
application of ac supply.
Rotor:
These are made of several thin steel lamination with evenly spaced bars, which are made up of
alluminium or copper , along the periphery. In the most popular type of rotor, these bars are
connected at ends mechanically and electrically by the use of rings.The rotor consists of a carrying
the conductor.
Speed of induction motor:
Ns= 120 f / p
Ns=synchronous speed of stator
P= the no. poles
F= supply in freq.
Controlling of 1-phase motor through auto transformer:
Two or more contactors may be used to provide reduced voltage starting of a motor. By using an
auto-transformer or a series inductance, a lower voltage is present at the motor terminals, reducing
starting torque and inrush current. Once the motor has come up to some fraction of its full-load
speed, the starter switches to full voltage at the motor terminals. Since the autotransformer or series
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reactor only carries the heavy motor starting current for a few seconds, the devices can be much
smaller compared to continuously rated equipment. The transition between reduced and full voltage
may be based on elapsed time, or triggered when a current sensor shows the motor current has began
to reduce.
Circuit Diagram:-
Figure
Figure:-
Precaution:-
1. Connection should be proper. Loose connection is not allowed.
2. Do not touch any live wire or part.
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3. Before switch on the supply, the connection should be checked by lab assistant.
4. Do not damage the terminals of part or wire etc.
Procedure:-
1. Make connectiondiagram as shown in fig 3.1.
2. Put input voltage at “zero”.
3. Now slowly vary input voltage and measure the speed by Tachometer.
4. Record the value of speed at various voltages.
Observation Table:-
S.No Input voltage
(volt.)
Speed(rpm)
1. 50V
2. 100V
3. 150V
4. 200V
5. 230V
Calculations:-
Results:- Thus we have prepare the connection and working principal of single phase induction
motor through 1-phase auto transformer and got the speed regulation with varying the input voltage.
References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
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Viva- Voice:-
Que.1) What is the type of induction motor?
Que.2) What is the speed of induction motor?
Que.3) What is an auto- transformer?
Que.4) What is the function of speed regulator?
Que.5) Which typr of induction motor is self start?
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EXPERIMENT NO. 4
Aim:- Prepare the connection of 3-phase squirrel cage induction motor through 3-phase auto
transformer and vary the speed.
Apparatus Required:-
S. No. Name Type Range /Rating Quantity
1 3- phase induction
Motor
Squirrel-cage 230V, 1 or 2HP, 1500 RPM
50Hz
1
2 Volt meter M I (0-600V)/(0-300V) 1/1
3 Ammeter M I 2A/5A 1/1
4 Auto transformer 1-phase 230V/(0-270V) 1
5 Tachometer Digital 0-2000rpm 1
6 Wattmeter Dynamometer 10/20A, 300/600V,
1800/2000W
2
Theory:-
3-Induction Motors:
An induction or asynchronous motor is a type of AC motorare widely used in industrial and
commercial application. They are classified either as squirrel cage. These motor are self starting and
use no capacitor, start winding, centrifugal switch or other starting device.
They produce medium to high degrees of starting torque. The power capabilities and efficiency in
these motors range from medium to high compared to their 1- phase counter parts. Popular
application include grinders, lathes etc.
Squirrel cage:-
Almost 90%of 3-phase ac induction motors are use of this type. The rotor is of the squirrel cage type
and its work as explained earlier. The power rating range from one-third to several
hundredhorsepower. Motor of this type, rated one horsepower or larger, cost and can start heavier
loads than their 1-phase.
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Stator:
The stator is made of the several tin lamination of aluminium or cast iron.they are punched and
clamped together to form a hollow cylinder.coils of insulation wires are inserted in to these slots.
Each grouping of coils , together with the core it surround , forms an electromagnet on the
application of ac supply.
Rotor:
These are made of several thin steel lamination with evenly spaced bars, which are made up of
aluminium or copper , along the periphery. In the most popular type of rotor, these bars are
connected at ends mechanically and electrically by the use of rings.The rotor consists of a carrying
the conductor.
Speed of induction motor:
Ns= 120 f / p
Ns=synchronous speed of stator
P= the no. poles
F= supply in freq.
Basic operation:
In Induction motor, the stator is powered with alternating current (poly phase in large machines) and
designed to create a rotating magnetic field which rotates in time with the AC oscillations. In an
induction motor the rotor rotates at a slower speed than the stator field. Therefore the magnetic field
through the rotor is changing (rotating). The rotor has windings in the form of closed loops of wire.
The rotating magnetic flux induces currents in the windings of the rotor as in a transformer.
According to Lenz's law the rotor windings will try to oppose the cause of production of induced
current in the rotor. The cause of induced current in the rotor is the rotating stator magnetic field, so
to oppose this the rotor will start to rotate in the direction of the rotating stator magnetic field to
make the relative speed between rotor and rotating stator magnetic field zero, thus the motor will
start.
For these currents to be induced, the speed of the physical rotor must be lower than that of the
stator's rotating magnetic field ( ), or the magnetic field would not be moving relative to the rotor
conductors and no currents would be induced. As the speed of the rotor drops below synchronous
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speed, the rotation rate of the magnetic field in the rotor increases, inducing more current in the
windings and creating more torque. The ratio between the rotation rate of the magnetic field as seen
by the rotor (slip speed) and the rotation rate of the stator's rotating field is called "slip". Under load,
the speed drops and the slip increases enough to create sufficient torque to turn the load. For this
reason, induction motors are sometimes referred to as asynchronous motors. An induction motor can
be used as induction generator, or it can be unrolled to form the linear induction motor which can
directly generate linear motion.
Controlling of 3-phase motor through auto transformer:
Two or more contactors may be used to provide reduced voltage starting of a motor. By using an
auto-transformer or a series inductance, a lower voltage is present at the motor terminals, reducing
starting torque and inrush current. Once the motor has come up to some fraction of its full-load
speed, the starter switches to full voltage at the motor terminals. Since the autotransformer or series
reactor only carries the heavy motor starting current for a few seconds, the devices can be much
smaller compared to continuously rated equipment. The transition between reduced and full voltage
may be based on elapsed time, or triggered when a current sensor shows the motor current has began
to reduce.
Circuit Diagram:-
Figure
Precaution:-
1. Connection should be proper. Loose connection is not allowed.
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2. Do not touch any live wire or part.
3. Before switch on the supply, the connection should be checked by lab assistant.
4. Do not damage the terminals of part or wire etc.
Procedure:-
1. Makeconnection diagram as shown in fig.
2. Put input voltage at “zero”.
3. Now slowly vary input voltage and measure the speed by Tachometer.
4. Record the value of speed at various voltages.
Observation Table:-
S.No. Input
voltage
(volt.)
Speed(rpm) Current( I) Wattmeter
W1 (P1)
Wattmeter
W2 ( P2)
1.
2.
3.
4.
5.
Calculations:-
Results:- Thus we have successfully prepare the connection and study of operation of 3- phase
squirrel cage induction motor and controlled the speed of induction motor by varying input voltage.
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References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
Viva- Voice:-
Que.1) What do you mean by 1 HP?
Que .2) How does rotation of 3-phase induction motor reversed?
Que.3) Why the stator of an induction motor is laminated?
Que 4) Why squirrel cage induction better than slip ring induction motor?
Que-5) What is the phase displacement in space between two windings of single phase induction
motor?
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EXPERIMENT NO. 5(A)
Aim:- Prepare the connection and testing of a fluorescent tube light.
Apparatus Required:-
S.
No.
Name Range Quantity
1 Fluorescent tube 40W, 230V,
50Hz, 120cm
1
2 Choke coil 40W,230V,
Cos φ=0.5
1
3 Starter Glow type for
20/40/65/80W tube
2
4 Test lamp 15W/100W/200W 1/1/1
5 Connecting leads -------- As per required
Theory:-
A fluorescent lamp is a gas-discharge lamp that uses electricity to excitemercuryvapor. The excited
mercury atoms produce short-wave ultraviolet light that then causes a phosphor to fluoresce,
producing visible light. A fluorescent lamp converts electrical power into useful light more
efficiently than an incandescent lamp. Lower energy cost typically offsets the higher initial cost of
the lamp. The lamp fixture is more costly because it requires a ballast to regulate the current through
the lamp.
A fluorescent lamp contains following parts:-
Construction-:
(1) Fluorescent tube
(2) Choke or ballast
(3) Starter s
(1) Fluorescent tube-:
A fluorescent lamp tube is filled with a gas containing low pressure mercury vapor and argon,
xenon, neon, or krypton. The pressure inside the lamp is around 0.3% of atmospheric pressure. The
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inner surface of the bulb is coated with a fluorescent (and often slightly phosphorescent) coating
made of varying blends of metallic and rare-earthphosphor salts. The bulb's electrodes are typically
made of coiled tungsten and usually referred to as cathodes because of their prime function of
emitting electrons. For this, they are coated with a mixture of barium, strontium and calcium oxides
chosen to have a low thermionic emissiontemperature. Compact fluorescent lamps have several
small-diameter tubes joined in a bundle of two, four, or six, or a small diameter tube coiled into a
spiral, to provide a high amount of light output in little volume.
(2)
Choke or ballast-:
Instant start ballast starts lamps without heating the cathodes at all by using high voltage (around 600
V). It is the most energy efficient type, but gives the least number of starts from a lamp as emissive
oxides are blasted from the cold cathode surfaces each time the lamp is started. This is the best type
for installations where lamps are not turned on and off very often. Rapid start ballast applies voltage
and heats the cathodes simultaneously. It provides superior lamp life and more cycle life, but uses
slightly more energy as the cathodes in each end of the lamp continue to consume heating power as
the lamp operates. A dimming circuit can be used with dimming ballast, which maintains the heating
current while allowing lamp current to be controlled. Programmed-start ballast is a more advanced
version of rapid start. This ballast applies power to the filaments first, then after a short delay to
allow the cathodes to preheat, applies voltage to the lamps to strike an arc. This ballast gives the best
life and most starts from lamps, and so is preferred for applications with very frequent power cycling
such as vision examination rooms and restrooms with a motion detector switch.
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Fig. ballast
Starter-:
The automatic glow starter shown in the photograph to the left consists of a small gas-discharge
lamp, containing neon or argon in parallel with a normally-open bi-metallicswitch. It functions as a
time-delay switch, turning the filaments of the fluorescent tube on for a few seconds to start it, and
then turning them off. When power is first applied to the circuit, a glow discharge will appear over
the electrodes in the starter lamp. This glow discharge will heat the gas in the starter and cause the
bi-metallic contact to bend towards the other contact. When the contacts touch, the two filaments of
the fluorescent lamp and the ballast will effectively be switched in series to the supply voltage. The
current through the filaments causes them to heat up and emit electrons into the tube gas by
thermionic emission
Starter
Connection and working of fluorescent lamp-:
Connection of fluorescent lamp is shown in the fig (a). In this connection one pin of both side is
connected with starter’s terminals separately
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Fig (a) connection of fluorescent lamp
When the light is turned on, the electric power heats up the cathode enough for it to
emit electrons (thermionic emission). These electrons collide with and ionize noble gas atoms inside
the bulb surrounding the filament to form a plasma by the process of impact ionization. As a result
of avalanche ionization, the conductivity of the ionized gas rapidly rises, allowing higher currents to
flow through the lamp.
The fill gas helps determine the operating electrical characteristics of the lamp, but does not give off
light itself. The fill gas effectively increases the distance that electrons travel through the tube, which
allows an electron a greater chance of interacting with a mercury atom. Argon atoms, excited to a
metastable state by impact of an electron, can impart this energy to a neutral mercury atom and
ionize it, described as the Penning effect. This has the benefit of lowering the breakdown and
operating voltage of the lamp, compared to other possible fill gases such as krypton.
Circuit Diagram:-
Figure
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ADVANTAGE:-
1. Longer life of about 7500 working hours.
2. High efficiency about 40 lumes/watt.
3. It is economical in use in long run.
4. Available in different colors.
DISADVANTAGE:-
1. Its initial cost is too high.
2. Fixing of its accessories takes time.
3. Its power factor is low.
Precaution:-
1. Connection should be proper. Loose connection is not allowed.
2. Do not touch any live wire or part.
3. Before switch on the supply, the connection should be checked by lab assistant.
4. Do not damage the terminals of part or wire etc.
Procedure:-
1. Make the connection as per as diagram.
2. Connections check and give the supply.
3. When lamp does not glow then filament open.
4. When lamp bright glow then filament is short.
5. When dim glow then filament is in proper working condition.
Observation Table:-
S.No. Test For Test Result
1. Choke coil
2. starter
3. Tube light
4. Fluorescent tube
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Calculations:-
Results:- we have successfully connection and study of fluorescent lamp and testing of testing of its
various parts has been done.
References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
Viva- Voice:-
Que .1) Filament of lamp is made by….?
Que 2) What is the use of inert gas in lamps?
Que3) Why filament is in coil shape?
Que -4) What is the composition of inert gases used in filament lamp?
Que.-5)What is life of approx. incandesend lamp?
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EXPERIMENT NO. 5(B)
Aim:- To prepare the connection of halogen lamp and measure voltage and current.
Apparatus Required:-
S.No. Name Range Qty
1. Copper ballast 220-240V,1A,
P.F.=0.5
1
2. Capacitor 250V, 10 MICRO
FARAD
1
3. DPMCB 6A, 250V 1
4. Helogen lamp 500W, 250V 1
5. Helogen lamp holder 5A 1
Theory:-
The halogen lamp is the latest member in the family of incandescent lamp. It numerous advantages
over the ordinary incandescent lamp. As already stated the life and efficiency of an incandescent
lamp fall of with use-partly due to slow evaporation of the filament and partly due to back deposit
formed on the inside of the inside of the bulb.
The addition of small amount of halogen vapours to the filling gas restores port of the evaporated
tungsten vapour back to filament by means of chemical reaction i.e. there is a sort of regeneration
cycle.
Advantage:-
1. No dimensions of lamp miniature size.
2. Long life-20000 hours.
3. Better colour rendition.
Application:-
Halogen lamp (up to 5 KW) –
Playing Field, Large Garden,Car Parking, T.V. , Studio Etc.
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Circuit Diagram:-
Figure:-
Precaution:-
1. Connection should be proper. Loose connection is not allowed.
2. Do not touch any live wire or part.
3. Before switch on the supply, the connection should be checked by lab assistant.
4. Do not damage the terminals of part or wire etc.
Procedure:-
1. Make the connection as per as diagram.
2. Connections check and give the supply.
3. When lamp does not glow then filament open.
4. When lamp bright glow then filament is short.
5. When dim glow then filament is in proper working condition.
Observation Table:-
S.No Switch Condition Voltage(v) Current(I)
1. S1 On
2. S1 Off
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Calculations:-
Results:- we have successfullyprepare the connection and study of halogen lamp and measure
voltage and current.
References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
Viva- Voice:-
Ques 1.)Why halogen lamp popular than other lamps?
Ques 2.) What is diff. b/w resistivity and specific resistance?
Ques 3.)What do you mean by resistor?
Que -4) What is the composition of inert gases used in filament lamp?
Que.-5) What is life of approx. incandesend lamp?
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EXPERIMENT NO. 5(C)
Aim:- To prepare the connection of sodium vapour lamp and measure voltage and current.
Apparatus Required:-
S.No Name Range QTY.
1. Hpsv lamp 220-250V,70W 1
2. Hpsv lamp holder 5A 1
3. Copper ballast 220-240V,1A, P.F.=0.34 1
4. Igniter 20000V 1
5. Capacitor 250V,10 MICRO FARAD 1
6. DPMCB 6A, 250V 1
7. Leads RED,BLACK,YELLOW 1
Theory:-
The practically lamp of this development of this type of lamp, however was delayed since
ordinary glass cannot with stand the chemical action of hot sodium.
The sodium vapour lamp consists of bulbs containing a small amount of metallic sodium,to
develop enough heat to vaporize the sodium.Since long discharge paths are necessary therefore,
the discharge envelope is usually bent into u-shape.
The lamp operates at temp. 300 degree temp in order to conserve the heat generate and assure the
lamp operating at normal air temp.
The discharge envelope is closed in a special vacuum envelop designed for this purpose. The
lamp must be operated horizontally or nearly so, to keep the sodium well spread out along the
tube, although some small lamp, may be operated vertically lamp up.
The sodium vapour lamp is only suitable for alternate current and therefore requires chocke
control. This requirement is met by operating the lamp for a stray field step-up-tapped auto
transformed auto transformed with an open circuit secondary voltage of 470-480 volts. The
uncorrected power factor is very low.
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When is not in operation , the sodium is usually in the form of solid deposited on the side walls of
tube, therefore at first when it is connected across the supply mains, the discharge takes places in
the neon gas. The metallic sodium vaporizes and then ionizes.
The efficiency of a sodium vapour lamp under practically condition is about 40-50 lumens/watt. The
major application of this type of lamp is for high way and generator outdoor lighting where colour
discrimination is not required, as required, such as street lighting parks , rail yards,lamps are
manufactured in 45,60,85and is not affected by voltage variation at the end of this period the light
output will be reduced by 15% due to ageing.
Advantage:-
1. No dimensions of lamp miniature size.
2. Long life-20000 hours.
3. Better colour rendition.
Circuit Diagram:-
Figure.
32. Stani Memorial College of Engineering And Technology, Phagi
Electrical Engineering
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Precaution:-
1. Connection should be proper. Loose connection is not allowed.
2. Do not touch any live wire or part.
3. Before switch on the supply, the connection should be checked by lab assistant.
4. Do not damage the terminals of part or wire etc.
Procedure:-
1. Make the connection as per as diagram.
2. Connections check and give the supply.
3. When lamp does not glow then filament open.
4. When lamp bright glow then filament is short.
5. When dim glow then filament is in proper working condition.
Observation Table:-
S.No Switch Condition Voltage(v) Current(I)
1. S1 on
2. S1 off
Calculations:-
Results:- we have successfully connection and study of Sodium vapour lamp with measure the
voltage and current.
References:-
1. O P Arora: Power Electronics Laboratory-Experiments and Organization, Narosa Pub.
2. P B Zbar: Industrial Electronics- A Text-Lab Manual, Tata McGraw Hill
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Viva- Voice:-
Que.1.) What is the function of ignitor in sodium vapour lamps?
Que.2) What is life and efficiency of SV lamps?
Que3.)How much time taken by sodium vapour lamp to full glow?
Que -4) What is the composition of inert gases used in filament lamp?
Que.-5) What is life of approx. incandesend lamp?
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Dear Sir,
I am writing this letter to submit my request to release me from lecturer till 30-June-2014 with Stani
Memorial College of Engineering and Technology, Jaipur. Though was enjoying working with this
professional environment of SMCET but some compulsive circumstances made me take this action.
Thank you for all of the support you and the college community have given me. I will never forget
your generosity and the important skill. I will forever cherish the time I spent with my students,
colleagues, and this community.
I will be sure to complete all grading and associated responsibilities before departing this position.
Please let me know what further steps or duties must be completed before my departure. I hope to
stay in touch with you and our community. Thank you again for all of your support.