Department of EEE
Circuit Theory Lab Manual
Instructions to Students Working in Electrical and Electronics Laboratories
Every student should come with right fitting dress & wear shoes with rubber soles.
Every student should avoid wearing metal ornaments like ring, bangles, bracelets, chains etc.
The circuit diagrams should be approved by the Teaching faculty in the laboratory.
The approved indent slip should be given in the store and receive the apparatus box.
These apparatus must be brought from the stores and kept on the worktable in a neat manner,
such a way that the connections are made conveniently.
Make the connections as per the diagram approved.
Get the connections be checked by the Lab Instructor in charge in the laboratory.
The Lab Instructor will arrange to give the supply to the worktable.
After ascertaining, the supply is given to the worktable, and students can proceed to conduct
the experiment as per the instruction issued.
If there is any difficulty experienced in the conduct of the experiment immediately call the Lab
Instructor and get over the difficulty.
After finishing the experiment, switch off the supply, show the observations to the Lab
Instructor, and get approved.
Request the Lab Instructor to make arrangements to switch off the supply to the worktable.
After ascertaining that the supply is switched off, disconnect and return the apparatus box to
the store.
Complete experiment should be recorded in the laboratory record notebook and shown to the
Teaching faculty in the next class.
If there is any damage to any material during transit or conduct of the experiment, all the
students in that particular group/batch are responsible.
Every student should take utmost care not to touch any live points, while they work in the
Laboratory.
Every student should keep his/her laboratory record with his/her safely till the
concerned practical examination is over.
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Circuit Theory Lab Manual
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Department of EEE
Circuit Theory Lab Manual
CONTENT
SL.NO
NAME OF THE EXPERIMENTS
PAGE NO
SIGNATURE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
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Circuit Theory Lab Manual
INTRODUCTION ABOUT COMPONENTS
RESISTORS:
Opposition to flow of currents is called resistance. The elements having
resistance are called resistors. They are of two types
Fixed resistor
Variable resistor
CAPACITORS:
Capacitors are used to store large amount of
static current. When they are included in circuit it acts open
circuit. They are three types
1. Disk capacitor
2. Fixed capacitor
3. Variable capacitor
TRANSFORMERS:
Transformers are used to transfer the current.
They are of two types
1. Step up Transformer
2. Step down Transformer
SEMICONDUCTORS:
Semiconductors are partial conductors which conducts electricity partially
through them. They play major role in electronics.
1 P-N Junction diode
2. Zener diode
Semiconductor is a material for which the width of the forbidden gap between the
valence band conduction is very small. As gap is every small valence electron
acquire required energy to go in to the conduction band. These free electrons
constitute of current under the influence of applied electric field. The energy band is
time for semiconductor. They are a class of material whose electrical conductivity
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Circuit Theory Lab Manual
lies between that of a conductor and an insulator. The conductivity of a
semiconductor lies in a range of10^5 and 10^-4siemens/meter.
INDUCTOR SPECIFICATIONS:
1. Inductance Value
2. Resistance
3. Capacitance
4. Frequency Value
5. Quality Factor
6. Power Losses
7. Current Ratings
8. Electro Magnetic Radiations
9. Temperature Coefficient
SWITCHES:
SPST: Single pole single through
SPDT: Single pole double through
DPST: Double pole single through
DPDT: Double pole double through
DIODES:
Diodes have more priority now a days. They are mostly used in
developing electronic systems. They are
1.
P-N Junction diode
2.
Zener diode
Zener diode is background biasing voltage. So it also called voltage requesting
diode.
CIRCUIT DIAGRAM:
RESISTORS:
-fixed resistor
-variable resistor
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Circuit Theory Lab Manual
RESISTOR COLOR CODE
The resistance value and tolerance of carbon resistor is usually indicated by color
coding. Color bands are printed on insulating body. They consist of four color
bands or 5 color bands & they are read from left to right.
A typical resistor with color bands is shown in figure
The above resistor has 4
color bands. The first
band represents first digit
The second band represent second digit
The third band represent multiplier (this gives the no. of zeros after
the 2 digits ) The 4th band represents tolerance in %
The color codes are presented in below table
COLOR
First digit
for the 1st
band
Second
digit for the
nd
2
Multiplier
digit for the
rd
Resistance
band
3 band
tolerance
Black
0
0
10^0
-
Brown
1
1
10^1
±1%
Red
2
2
10^2
±2%
Orange
3
3
10^3
±3%
Yellow
4
4
10^4
-
Green
5
5
10^5
-
Blue
6
6
10^6
-
Violet
7
7
10^7
-
Gray
8
8
10^8
-
White
9
9
10^9
-
Gold
-
-
10^-1
±5%
Silver
-
-
10^-2
±10%
No color
-
-
-
±20%
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Circuit Theory Lab Manual
If third band is gold the first two digit are multiplied by 10^-1
If the third band is silver the first two digits are multiplied by 10^-2
If the 4th band is gold the tolerance is ±5%
If the 4th band is silver is the tolerance is ±10%
If the 4th band is no color the tolerance is ±20%
The numerical value associated with each color
B
B
R
O
Y
G
B
V
G
W
black
brown
red
orange
Yellow
green
blue
violet
gray
White
0
1
2
3
4
5
6
7
8
9
EXAMPLES:
The resistor has a color band sequence green, blue, brown and silver identify the
resistance value.
1ST Band
2nd band
3rd band
4th band
1st digit
2nd digit
multiplier
tolerance
5
6
10^1
±10%
The resistance value=56x10^1±10% =560Ω±10%
Therefore the resistance should be within the range of 555Ω to 565Ω
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Circuit Theory Lab Manual
VERIFICATION OF KIRCHOFF’S LAWS USING HARDWIRED COMPONENTS
Verification of Kirchoff's Current Law
Verification of Kirchoff's Voltage Law
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Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF KIRCHOFF’S LAWS
AIM
(i)
To verify the Kirchoff’s laws using hardwired components
(ii)
To verify the Kirchoff’s laws using Multisim workbench
APPARATUS REQUIRED:
SLNO
NAME
1.
RPS
2
AMMETER
3
VOLTMETER
4
RHEOSTATS
TYPE
RANGE
QTY
Software Required:
Multisim 12
Theory:
Kirchoff’S Current Law
At any node (junction) in an electrical circuit, the sum of currents flowing into that node is
equal to the sum of currents flowing out of that node, or:
The algebraic sum of currents in a network of conductors meeting at a point is zero.
N
∑ IK =0
K=1
N is total no. of branches with currents towards and away from the node
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Circuit Theory Lab Manual
VERIFICATION OF KIRCHOFF’S LAWS USING MULTISIM SOFTWARE COMPONENTS
Verification of Kirchoff's Current Law
Verification of Kirchoff's Voltage Law
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Circuit Theory Lab Manual
Kirchoff’S Voltage Law
Any closed loop in a circuit, the algebraic sum of the potential differences across all elements
is zero
N
∑ VK =0
K=1
PROCEDURE:
Kirchoff’s Current law
1. Connection made as per the circuit diagram.
2. Switch the ON the supply
3. The potential divider is gradually varied in steps and each step the reading of ammeters
noted down.
4. The readings are tabulated.
Repeat same procedure for KVL also
PROCEDURE (MULTISIM WORKBENCH):
1. Build a circuit as per the circuit diagram on Multisim electronics workbench.
2. Save the circuits in your folder.
3. Click start simulation.
4. The potential divider is gradually varied in steps and each step the reading of ammeters
noted down.
5. The readings are tabulated.
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Circuit Theory Lab Manual
TABULATION (HARDWIRED)
Kirchoff’s current law
S.No.
I (A)
I1 (A)
I2(A)
I (A)
I1 (A)
I2(A)
Kirchoff’s Voltage law
S.No.
TABULATION (MULTISIM SOFTWARE)
Kirchoff’s current law
S.No.
I (A)
I1 (A)
I2(A)
I (A)
I1 (A)
I2(A)
Kirchoff’s Voltage law
S.No.
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Circuit Theory Lab Manual
RESULT:
Hence the Kirchoff’s laws were verified using both hardwired components and MULTISIM
workbench.
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Circuit Theory Lab Manual
VERIFICATION OF THEVENIN'S THEOREM
To calculate the Rth
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Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF THEVENIN'S THEOREM
AIM:
To verify Thevenin's theorem
APPARATUS REQUIRED:
SLNO
NAME
1.
RPS
2
AMMETER
3
VOLTMETER
4
RHEOSTATS
5
Connecting Wires
TYPE
RANGE
QTY
THEORY:
STATEMENT
Thevenin’s theorem states that any linear two-terminal circuit can be replaced by an
equivalent circuit consisting of a voltage source VTh in series with a resistor RTh.
Thevenin’s Theorem states that “Any linear circuit containing several voltages and
resistances can be replaced by just one single voltage in series with a single resistance connected
across the load“. In other words, it is possible to simplify any electrical circuit, no matter how
complex, to an equivalent two-terminal circuit with just a single constant voltage source in series with
a resistance (or impedance) connected to a load
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Circuit Theory Lab Manual
TABULATION
MEASURED VALUES
Supply
S.No
THEORITICAL VALUES
voltage
(volts)
VTH (V)
RTH (Ω)
IL (mA)
16
VTH (V)
RTH (Ω)
IL (mA)
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PRECAUTIONS:
1. All the connections should
tight.
2. The rheostats should be set at suitable positions so that the current in ammeter is less
than the rheostat current ratings. This value of current
also be readable.
3. Before connecting the instruments check their zero settings.
4.
The terminals
the rheostats should be connected properly.
5. At no instant of the time the current in ammeter should exceed the current rating
of rheostats.
STEPS TO BE FOLLOWED IN APPLYING THEVENIN’S THEOREM
1. Let the load resistance be RL through which the current IL is required. Mark the terminals A
and B across which RL is supposed to be connected between the terminals marked as
A and B.
2. Blindly, draw the thevenin’s equivalent circuit between A snd B terminals. It is the constant
voltage source with voltage VTH nand resistance RTH.
3. In the given circuit disconnect RL and redraw the figure. After removing the RL find the
voltage between A and B. It is VTH.
4. From the circuit in the above step,kill all the energy sources properly and obtained
resistance between A and B when looked back. It is RTH
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MODEL CALCULATION:
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Circuit Theory Lab Manual
RESULT:
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Circuit Theory Lab Manual
NORTON’S THEOREM
Circuit Diagram:
To find Isc or IN
To find RN
To find IL
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Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF NORTON’S THEOREM
AIM
To verify the Norton’s theorem theoretically and practically for a given circuit
APPARATUS REQUIRED
S.NO
APPARATUS
RANGE
TYPE
QTY
1.
DC Regulated power supply
(0-30)V,2A
-
1
2.
Ammeter
(0-50)mA
MC
1
4.
Resistance
(150Ω,390Ω,270Ω,330Ω), 1/4W
5.
Bread board
-
-
1
6.
Connecting wires
-
-
as required
Each one
STATEMENT
Norton’s theorem states that any linear two-terminal circuit can be replaced by an equivalent
circuit consisting of a current source IN in parallel with a resistor RN.
PROCEDURE
a) To find IL
1. Connections are given as per the circuit.
2. The Load current IL is noted for various values of supply voltage and tabulated.
b) To find Isc
1. Connections are modified as shown in the circuit.
2. The short circuit current (ISC) is noted for various values of the supply voltage and
tabulated.
3) Norton’s resistance is practically calculated by using the Open circuit voltage and short circuit
current
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Circuit Theory Lab Manual
TABULATION
Supply
S.No
MEASURED VALUES
THEORITICAL VALUES
voltage
(volts)
ISC (mA)
RN (Ω)
IL (mA)
ISC (mA)
RN (Ω)
IL (mA)
NORTON EQUIVALENT CIRCUIT
MODEL CALCULATION
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Circuit Theory Lab Manual
RESULT
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM (MAXIMUM POWER TRANSFER THEOREM) HARDWIRED
To find VTH
To find Il
To find RTH
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Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF MAXIMUM POWER TRANSFER THEOREM
AIM
i. To verify the Maximum power transfer theorem theoretically and practically for a given circuit
using hardware components.
ii. To verify the Maximum power transfer theorem theoretically and practically for a given circuit
using Multisim software.
APPARATUS REQUIRED
S.NO
APPARATUS
RANGE
TYPE
QTY
1.
DC Regulated power supply
(0-30)V,2A
1
2.
Ammeter
(0-5mA)
MC
1
3.
Voltmeter
(0-10V)
MC
1
4.
Decade resistance box
-
-
1
5.
Resistors
(10KΩ, 22KΩ ),¼ W
-
1Each
6.
Bread board
-
-
1
7.
Connecting wires
-
-
As required
STATEMENT
Maximum power is transferred to the load when the load resistance equals the Thevenin’s
resistance as seen from the load (RL = RTh).
PROCEDURE
1. Connections are made as per the circuit diagram.
2. A fixed supply voltage is applied using RPS.
3. Find VTH and RTH for the given circuit.
4. Vary the load resistance (RL) and note down the corresponding load currents IL
Calculate the Power using the formula.
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Circuit Theory Lab Manual
TABULATION:
Load
Measured values
Theoretical values
Power=IL2RL
resistance
(RL)
VTH
RTH
IL
VTH
RTH
IL=vTH/(RTH+RL)
MODEL CALCULATION
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM (MAXIMUM POWER TRANSFER THEOREM) MULTISIM SOFTWARE
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Circuit Theory Lab Manual
TABULATION
RL in
%
VL(v)
V S(v)
I L(A)
Rs=V S/I
R L=V
P=V LI
L(Ω)
L/IL(Ω)
L(w)
100 %
90 %
80 %
70 %
60 %
50 %
40 %
30 %
20 %
10 %
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PROCEDURE (MULTISIM Workbench):
1. Connect the circuit as shown.
2. Keep the variable point of potentiometer RL at its maximum position by pressing Key A.
3. Adjust the value of resistor Rs at some suitable Value.
4. Decrease RL using press Shift+key A and note the Wattmeter, voltmeters and
ammeter readings till RL reaches a low value.
Repeat the steps 2, 3 and 4 with a different position of rheostat Rs
CALCULATIONS:
The values of Rs and RL can be calculated by using the following equations:
Rs=Vs/IL
RL=VL/IL
RESULT
Thus the Maximum Power transfer theorem is verified theoretically and practically for the
given circuit.
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM
MODEL GRAPH
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Circuit Theory Lab Manual
EX.NO:
DATE:
EXPERIMENTAL DETERMINATION OF TIME CONSTANT OF
SERIES R-C ELECTRIC CIRCUITS.
AIM
To Analyse and determine the transient response of an RC circuit for Dc input
APPARATUS REQUIRED
S.NO
APPARATUS
RANGE
Type
QTY
(0-30)V,2A
-
1
1
DC Regulated power supply
3
Voltmeter
(0-30)V
MC
1
4
Resistor
10K,1/4 W
-
1
5
Capacitor
4700𝜇F,16V
-
1
6
Connecting wires
-
-
As Required
THEORY
As the capacitors store energy in the form of an electric field, they tend to act like small
secondary-cell batteries, being able to store and release electrical energy. A fully discharged capacitor
maintains zero volts across its terminals, and a charged capacitor maintains a steady quantity of
voltage across its terminals, just like a battery. When capacitors are placed in a circuit with other
sources of voltage, they will absorb energy from those sources, just as a secondary-cell battery will
become charged as a result of being connected to a generator. A fully discharged capacitor, having a
terminal voltage of zero, will initially act as a short circuit when attached to a source of voltage,
drawing maximum current as it begins to build a charge. Over a time, the capacitor's terminal voltage
rises to meet the applied voltage from the source, and the current through the capacitor decreases
correspondingly.
Once the capacitor has reached the full voltage of the source, it will stop drawing current
from it, and behave essentially as an open-circuit. When the switch is first closed, the voltage across
the capacitor is zero volts; thus, it first behaves as though it were a short circuit. Over a time, the
capacitor voltage will rise to equal battery voltage, ending in a condition where the capacitor behaves
as an open-circuit.
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Circuit Theory Lab Manual
TABULATION
Capacitor voltage (volts)
Time (ms)
Time (seconds)
Capacitor voltage (volts)
T ON
T OFF
CALCULATION
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PROCEDURE
CHARGING
1. Connections are made as per the circuit diagram.
2. The power supply is switched ON and the voltage is set to 7 volts.
3. Close the switch to position 1 at time t=0 and observe the voltage across capacitor for every
5 seconds.
4. Plot a graph between voltage across the capacitor and time.
DISCHARGING
1. Close the switch to position 2 at time t=0. Now the capacitor starts discharging.
2. Observe the voltage across the capacitor and the corresponding time until the capacitor
discharges to zero volts.
RESULT
Thus the transient response of an RC circuit for DC input is determined
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM (Series RLC circuit)
TABULATION
Input Voltage Vi=
S.No
Frequency
In Hz
Output Voltage (Io)
in mA
Gain=20log(I0/Ii)
in dB
MODEL GRAPH
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EX.NO:
DATE:
EXPERIMENTAL DETERMINATION OF FREQUENCY RESPONSE OF RLC CIRCUITS
FREQUENCY RESPONSE OF SERIES RESONANCE CIRCUITS
AIM
To determine the resonant frequency and bandwidth of series resonant circuit
APPARATUS REQUIRED
S.NO
APPARATUS
RANGE
TYPE
QTY
3MHz,20VPP
-
1
1
Function Generator
2
Single dial decade resistance box
-
-
1
3
Single dial decade inductance box
-
-
1
4
Single dial decade capacitance box
-
-
1
5
Voltmeter
(0-10V)
MI
1
6
Ammeter
(0-10mA)
MI
1
7
Bread board
-
-
1
8
Connecting wires
-
-
As required
THEORY
Impedance (Z) for a serial RLC circuit is a function of the resistance ( R), the inductive
reactance (X ), and the capacitive reactance (X ):
L
C
𝑧 = √𝑅2 + (𝑋𝐿 − 𝑋𝐶 )2
Inductive reactance is a function of the inductance ( L) and frequency (f) of the AC voltage:
𝑋𝐿 = 2𝜋𝑓𝐿
Capacitive reactance is a function of the capacitance ( C) and frequency (f) of the AC voltage:
𝑋𝐶 =
1
2𝜋𝑓𝐶
If the sum of X and X is zero, then the equation for the resonant frequency in a series RLC circuit is:
L
C
𝜔𝑜 =
1
√𝐿𝐶
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Circuit Theory Lab Manual
CALCULATION:
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Circuit Theory Lab Manual
The resonance frequency (ωo) is the frequency at which the output is in phase with the
input. In other words, at resonance, circuit is operating at unity power factor (purely resistive circuit).
The bandwidth (β) is defined as the range of frequencies for which the peak amplitude of the
response is at least 1√2 times the maximum peak amplitude. The quality factor (Q) of the resonant
circuit recognizes this attribute of frequency selectivity since it is defined as the ratio of the resonant
frequency to the bandwidth. Bandwidth of the series resonant circuit is defined as:
𝛽 = 𝜔2 − 𝜔1 =
𝑅
𝐿
Quality factor is defined as:
𝑄=
𝜔𝑜 𝜔𝑜 𝐿
1
1 𝐿
=
=
= √
𝛽
𝑅
𝜔𝑜 𝐶𝑅 𝑅 𝐶
PROCEDURE
1. Make the connections as shown in the circuit diagram.
2. Set the input current (Ii) by using function generator as 2mA.
3. Increase the frequency and note down the corresponding output current (I o).
4. Find the frequency at which the output current Io is maximum (Imax).
5. Calculate 0.707 of the maximum current.
6. Plot Gain (db) Vs f on semi-log paper.
RESULT
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CIRCUIT DIAGRAM (Parallel RLC circuit)
TABULATION
Input voltage Vi=
S.No
Frequency
In Hz
Output voltage (Vo)
in volts
Gain=20log(V0/Vi)
in dB
MODEL GRAPH
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EX.NO:
DATE:
EXPERIMENTAL DETERMINATION OF FREQUENCY RESPONSE OF RLC CIRCUITS
FREQUENCY RESPONSE OF PARALLEL RESONANCE CIRCUIT
AIM
To determine the resonant frequency and bandwidth of a parallel resonant circuit
APPARATUS REQUIRED
S.NO
APPARATUS
RANGE
TYPE
QTY
3MHz,20VPP
-
1
1
Function Generator
2
Five dial decade resistance box
-
-
1
3
Five dial decade inductance box
-
-
1
4
Five dial decade capacitance box
-
-
1
5
Voltmeter
(0-10)V
MI
1
6
Connecting wires
-
-
As required
THEORY
Impedance (Z) for a serial RLC circuit is a function of the resistance ( R), the inductive reactance ( X ),
L
and the capacitive reactance (X ):
C
𝑧 = √𝑅2 + (𝑋𝐿 − 𝑋𝐶 )2
Inductive reactance is a function of the inductance ( L) and frequency (f) of the AC voltage:
𝑋𝐿 = 2𝜋𝑓𝐿
Capacitive reactance is a function of the capacitance ( C) and frequency (f) of the AC voltage:
𝑋𝐶 =
1
2𝜋𝑓𝐶
If the sum of X and X is zero, then the equation for the resonant frequency in a series RLC circuit is:
L
𝜔𝑜 =
C
1
√𝐿𝐶
The resonance frequency (ωo) is the frequency at which the output is in phase with the
input. In other words, at resonance, circuit is operating at unity power factor (purely resistive circuit).
The bandwidth (β) is defined as the range of frequencies for which the peak amplitude of the
response is at least 1√2 times the maximum peak amplitude. The quality factor (Q) of the resonant
circuit recognizes this attribute of frequency selectivity since it is defined as the ratio of the resonant
frequency to the bandwidth. For a parallel circuit, impedance is:
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Circuit Theory Lab Manual
MODEL CALCULATION
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Circuit Theory Lab Manual
1
1
1 2
=
+
(2𝜋𝑓𝐶
−
)
𝑍 2 𝑅2
2𝜋𝑓𝐿
Bandwidth of the parallel resonant circuit is defined as:
𝛽 = 𝜔2 − 𝜔1 =
1
𝑅𝐶
The quality of the frequency response in parallel resonant circuit is described as:
𝑄=
𝑅
𝐶
= 𝜔𝑜 𝐶𝑅 = 𝑅 √
𝜔𝑜 𝐿
𝐿
PROCEDURE
1. Make the connections as shown in the circuit diagram.
2. Set the input current (Vi) by using function generator as 5V.
3. Increase the frequency and note down the corresponding output voltage (V o).
4. Find the frequency at which the output Voltage Vo is maximum (V max).
5. Calculate 0.707 of the maximum Voltage.
6. Plot Gain (dB) Vs f on semi-log paper.
RESULT
Thus the resonant frequency and bandwidth of Parallel resonant circuits are determined.
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SCSVMV UNIVERSITY
Department of EEE
Circuit Theory Lab Manual
CIRCUIT DIAGRAM (USING HARDWARE)
CIRCUIT DIAGRAM (USING MULTISIM SOFTWARE)
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Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF SUPERPOSITION THEOREM
AIM:
(i)
To verify the superposition theorem using Multisim workbench.
(ii)
To verify the superposition theorem using Hardwired Components.
APPARATUS REQUIRED:
S.No
Name
1
Resistors
2
Multimeter
3
Ammeter
4
DRB
5
RPS
Range
Quantity
SOFTWARE TOOLS:
Multisim 12
THEORY:
Superposition theorem helps us to find the current in any element due to the sources acting
simultaneously. This may be stated as follows:
“In a linear, lumped element, bilateral circuit, that is energized by two or more sources the
current in any resistor is equal to the algebraic sum of the separate currents in the resistor when
source acts separately. While one source is applied, the other sources replaced by their respective
internal resistances.”
To replace the other sources by their respective internal resistances, the voltage
sources are short-circuited and the current sources are open circuited.
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SCSVMV UNIVERSITY
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Circuit Theory Lab Manual
TABULAR COLUMN (Hardwired components):
With Both
sources(Z)
SL.No
A1
A2
A3
With 12V only
With 6V only
(X)
(Y)
A1X
A2X
A3X
A1Y
A2Y
A3Y
X+Y
A1
A2
A3
TABULAR COLUMN (Multisim workbench):
With Both
sources(Z)
SL.No
A1
A2
A3
With 12V only
With 6V only
(X)
(Y)
A1X
A2X
A3X
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A1Y
A2Y
A3Y
X+Y
A1
A2
A3
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Department of EEE
Circuit Theory Lab Manual
PRECAUTIONS:
1. All the connections should be tight.
2. Before connecting the instruments check their zero settings.
3. The terminals of the rheostats should be connected properly.
4. The directions of the currents should be correctly identified.
5. At no instant of time the reading in any ammeter should exceed the rating of the rheostats.
PROCEDURE (Hardwired components):
1. Connect the instruments, components and sources according the circuit shown in fig.
2. Put the rheostats at positions so that the readings in all the ammeters are within the range.
3. Note down the readings of all the ammeters.
4. Disconnect the 6v source and replace it by a short circuit by connecting the point C to F, and note
down the readings of all the three ammeters. For this step the rheostat position shouldn’t be
changed.
5. Now replace the 6v, D.C. source at its place. Remove the 12v, D.C. source and replace it by a
short circuit. This can be done by connecting the point A to E. again note down the readings
of all the three ammeters.
6. Change the settings of the rheostats and repeat the steps 3 to 5.
7. Repeat step 6 a number of times.
8. Add algebraically the readings of the corresponding ammeters obtained in Step 4 and in step 5.
Record those sums in the in the last column of table.
9. The sum recorded in the last column of the table should agree with the Corresponding entries
in 2nd, 3rd, and 4th columns of the table.
PROCEDURE (Hardwired components):
1. Build circuit Figure 1 on Multisim Electronics workbench
2. Save the circuit on your folder and click start simulation button
3. Note down the reading of all the ammeters
4. Repeat the step 1,2 & 3 for figure 2 and 3 also
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Circuit Theory Lab Manual
CALCULATION:
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Circuit Theory Lab Manual
RESULT:
Hence the superposition theorem was verified using both Multisim workbench and hardwired
components.
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM:
To Find I
To find I’
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SCSVMV UNIVERSITY
Department of EEE
Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF RECIPROCITY THEOREM
AIM:
(i) To verify the Reciprocity theorem using Multisim workbench.
(ii) To verify the Reciprocity theorem using Hardwired Components.
APPARATUR REQUIRED:
SL.NO
NAME
1
Resistors
2
Multi meter
3
Ammeter
4
DRB
5
RPS
RANGE
QUANTITY
SOFTWARE TOOLS:
Multisim 12
THEORY:
Reciprocity theorem stated as follows:
“In a linear, bilateral network, a voltage source ‘V’ volt in a branch gives to a current I in
another branch. If ‘V’ is applied in the second branch the current in the first branch will be I. This V/I
are called transfer impedance or resistance. On changing the voltage source from 1 to branch 2 the
current in branch 2 appears in branch 1”
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Circuit Theory Lab Manual
SIMULATION DIAGRAM
TABULATION
Sl.No
Voltage
(In loop A)
Current (I)
Calculated
Measured
50
Voltage
(In loop B)
Current (I’)
Calculated
Measured
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Circuit Theory Lab Manual
MODEL CALCULATION
RESULT
Hence the Reciprocity theorem was verified using both Multisim workbench and hardwired
components
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM (Hardwired Components)
CIRCUIT DIAGRAM (Multisim Software)
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Department of EEE
Circuit Theory Lab Manual
EX.NO:
DATE:
VERIFICATION OF COMPENSATION THEOREM
AIM:
i)
To verify the Compensation Theorem using Multisim workbench.
ii)
To verify the Compensation Theorem using Hardwired Components.
APPARATUR REQUIRED:
S.NO
NAME
1
Resistors
2
Multi meter
3
Ammeter
4
DRB
5
RPS
RANGE
QUANTITY
SOFTWARE TOOLS:
Multisim 12
THEORY:
Compensation theorem stated as follows:
“Impedance in a network may be replaced by an ideal voltage source whose generated EMF
at any instant is equal to the instantaneous potential differences across the impedance”
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Circuit Theory Lab Manual
TABULATION
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Circuit Theory Lab Manual
PROCEDURE (Hardwired components):
1. Connect the Circuit as per the circuit diagram.
2. Two resistors are connected in series using voltage and current sources.
3. The current through the circuit is noted using the ammeter. This gives the current I.
4. Another resistor is connected in series and I’ is noted using the ammeter.
5. Using the current I’ the voltage Vc through the circuit is found.
6. Now the voltage that was found is supplied to the circuit and I’’ is found.
7. This current I’’ is equal to the difference of I and I’
PROCEDURE (Using Multisim):
8. Build circuit Figure 1 on Multisim Electronics workbench
9. Save the circuit on your folder and click start simulation button
10. Note down the reading of ammeter
THEORETICAL CALCULATION:
RESULT:
[[
Hence the Compensation theorem was verified using both Multisim workbench and hardwired
components.
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SCSVMV UNIVERSITY
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM:
TO FIND I USING MESH ANALYSIS
TO FIND V USING NODAL ANALYSIS
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Department of EEE
Circuit Theory Lab Manual
EX. NO.
DATE:
VERIFICATION OF MESH AND NODAL ANALYSIS
AIM:
To verify the Mesh and Nodal analysis for the given Electrical Circuit
APPARATUS REQUIRED:
Sl.No.
Name of the Apparatus
Range
Type
Quantity
(0-30)V,2A
-
1
1
Regulated power supply
2
Resistors
1K,2.2K,560Ω,330Ω 1/4W
3
Voltmeter
(0-20V)
MC
1
4
Ammeter
(0-25mA)
MC
1
5
Bread board
-
-
1
6
Connecting wires
-
-
As reqd
1each
THEORY
Mesh and nodal analysis are two basic important techniques which are useful to find
solutions in a network. The suitability of either mesh or nodal analysis to a particular problem
mainly depends on the number of voltage sources or current sources. If a network has a
large number of voltage sources, it is useful to use mesh analysis; if, on the other hand, the
network has more current sources, nodal analysis is the useful method.
Mesh analysis is applied to most of the networks. Unfortunately, it is applicable only
for planar networks. For non planar circuits mesh analysis is not applicable. A circuit is said to
be planar, if it can be drawn on a plane surface without crossovers. A non planar circuit
cannot be drawn on a plane surface without a crossover.
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SCSVMV UNIVERSITY
Department of EEE
Circuit Theory Lab Manual
TABULATION
MESH ANALYSIS
NODAL ANALYSIS
Theoretical value
Practical Value
Theoretical value
Practical Value
I (mA)
I (mA)
V(volts)
V(volts)
MODEL CALCULATION
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SCSVMV UNIVERSITY
Department of EEE
Circuit Theory Lab Manual
PROCEDURE:
1) Connections are given as shown in the figure.
2) By using mesh method the circuit is solved and the loop currents are determined.
3) Connect ammeters in series with resistances in all branches.
4) Tabulate the readings and compare the practical values with theoretical values.
RESULT:
Thus the mesh and nodal analysis for the given electrical circuit is verified.
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SCSVMV UNIVERSITY
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM (Hard wired)
R1
R3
V1
CIRCUIT DIAGRAM (Multisim Software)
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Department of EEE
Circuit Theory Lab Manual
EX.NO.
DATE:
VERIFICATION OF MILLMAN’S THEOREM
AIM:
i)
To verify the Millman’s Theorem using Multisim workbench.
ii)
To verify the Millman’s Theorem using Hardwired Components.
APPARATUR REQUIRED:
S.NO
NAME
1
Resistors
2
Multi meter
3
Ammeter
4
DRB
5
RPS
RANGE
QUANTITY
SOFTWARE TOOLS:
Multisim 12
THEORY:
Millman’s theorem stated as follows:
In a network system, multiple current sources which are in parallel can be represented by a
single current source, having the sum of the individual source currents and the resistance of the
parallel combination of the individual source resistance.
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Circuit Theory Lab Manual
MODEL CALCULATION
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Circuit Theory Lab Manual
RESULT
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM
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Department of EEE
Circuit Theory Lab Manual
EX.NO.
DATE:
B - H CURVE OF A MAGNETIC MATERIAL
AIM:
To obtain the B - H curve of a magnetic material.
APPARATUS REQUIRED:
SI.No
Name
Type
1
Single phase variac
2.
Ammeter
3.
Voltmeter
4.
Core with main and search coils
Range
Quantity
THEORY:
When a magnetizing force {H) is applied to a magnetic material, a magnetic flux density
(B) is set up. The relation between the magnetizing force (H) and the flux density (B) is
B
=
1J
,.......................................
H
(1)
Where 11 = Permeability of the material.
For non - magnetic materials,
ll = lln = 4n X 10 -?
( 2)
For magnetic materials,
IJ=IJn IJ,,
Where -'•
is the relative permeability of material.
For the non-magnetic
magnetic
materials, the
permeability is constant
and is low.
For the
materials, however, the permeability is high and decreases under saturation.
The B - H curve is a very useful curve, since it describes the magnetic behavior of the
material. From this, one can know the magnetizing fora; required to work the material at a
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Circuit Theory Lab Manual
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Circuit Theory Lab Manual
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Circuit Theory Lab Manual
CALCULATION
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Circuit Theory Lab Manual
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Circuit Theory Lab Manual
CIRCUIT DIAGRAM
MODEL GRAPH
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Circuit Theory Lab Manual
EX.NO.
DATE:
FREQUENCY RESPONSE OF SERIES RESONANCE CIRCUIT
AIM:
To obtain the resonance frequency of the given RLC series electrical network using
Multisim workbench.
APPARATUS REQUIRED
S.NO
COMPONENTS
RANGE
QUANTITY
1
Function generator
0-2MHz
1
2
Resistor
1kohm
1
3
Voltmeter
(0-5)v
1
4
Capacitor
1microfarad
1
5
Decade inductance box
(0-100)mH
1
SOFTWARE TOOLS:
Multisim 12
FORMULA USED :
Series resonance frequency F = 1/(2л √LC)
PROCEDURE:
1. Connections are made as per the circuit diagram
2. Vary the frequency of the function generator from 50 Hz to 20 Hz
3. Measure the corresponding value of voltage across the resistor R for series RLC circuit.
4. Repeat the same procedure for different value of frequency.
5. Tabulate your observation
6. Note down the resonance frequency from the graph
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Circuit Theory Lab Manual
TABULATION
S.NO
FREQUENCY(HZ)
72
VOLTAGE(VOLT)
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Department of EEE
Circuit Theory Lab Manual
RESULT:
Thus the Resonance frequency of Series RLC circuits was obtained
Fs=
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