Manual 2

1

ELECTRICAL CIRCUITS LABORATORYMANUAL

(II – SEMESTER)

By

N.DHINESH KUMAR

2

LIST OF EXPERIMENTS

1. P-N Junction Diode Characteristics

2. A. Zener Diode Characteristics 6 B. Zener Diode As Voltage Regulator 10 3. Common Base characteristics Of A Transistor 14 4. Common Emitter Characterstics Of A Transistor 18 5. Half-Wave Rectifier With & Without Filter 22 6. Full-Wave Rectifier With & Without Filter 26 7. FET Characteristics 30 8.Silicon-Controlled Rectifier (Scr) Characteristics 52

9. Verification of Ohm’s laws and Kirchhoff’s laws.

10. Verification of Thevenin’s and Norton’s Theorem.

11. Verification of Superposition Theorem.

12. Verification of Maximum power transfer theorem.

13.Verification of Reciprocity theorem.14.Frequency response of Series and Parallel resonance circuits.

15. Transient response of RL and RC circuits for DC input.

3

9. A. VERIF ICATIO N OF OHM S LAW

AIM:

To conduct a suitable experiment for verifying the ohm’s law

APPARATUS REQUIRED:

S.NO. NAME OFTHE

EQUIPMENT

RANGE TYPE QTY.

1. RPS (0-30)V DC 12. Ammeter (0-10)mA MC 33. Voltmeter (0-10)V MC 34. Resistor 10KΩ - 35. Bread board - - 16. Connecting

wires- Single strand As required

THEORY:OHM`S LAW:

Ohm’s law states that at constant temperature the current flow through a conductor is directlyproportional to the potential difference between the two ends of the conductor.

I α V

Or V α I

V = IRWhere R is a constant and is called the resistance of the conductor.

FORMULA:

V = IRPROCEDURE:

Connections are made as per the circuit diagramSwitch on the power supply.

For various values of voltage V, note the values of current I.

Draw a graph of Voltage Vs Current.

The Slope of the graph gives the resistance value.

Ohm’s law is verified by measuring the value of R using multimeter and comparing

with the experimental value.

4

OHM`S LAW:

TABULATION:

MODEL CALCULATION & ANALYSIS:

MODEL GRAPH.

5

9 .B. VERIFICAT ION O F KVL & KCL

A IM :To verify (i) kirchoff’s current law (ii) kirchoff’s voltage law

(i) KIRCHOFF’S CURRENT LAW:

A PPAR A T U S R E Q U I R E D :

S.No Name of the apparatus Range Quantity

1

2

3

4

5

RPS

Resistor

Ammeter

Bread board

Connecting wires

(0-15)V

1 KΩ

(0-10)mA

------

------

1

3

3

1

As required

T H E O R Y :

Kirchoff’s current law:The algebraic sum of the currents entering in any node is Zero.

The law represents the mathematical statement of the fact change cannot accumulate at a node. A node is not a circuit element and it certainly cannot store destroy (or) generate charge. Hence the current must sum to zero. A hydraulic analog sum is zero. For example consider three water pipes joined pn the shape of Y. we defined free currents as following into each of 3 pipes. If we insists that what is always

PR O C E D U R E :

1. Connections are made as per the circuit diagram.2. Check your connections before switch on the supply.3. Vary the regulated supply.4. Measure the current using ammeter.5. Note the readings in the tabulation.6. Compare the observation reading to theoretical value.

6

ii) KIRC H OFF’ S V OL TAGE L AW:

APP ARATU S REQ UIRE D:

S.No Name of the apparatus

Range Quantity

1

2

3

4

5

RPS

Resistor

voltmeter

Bread board

Connecting wires

(0-15)V

1KΩ,2.2KΩ,3.3KΩ

(0-20)V

------

------

1

Each 1

3

1

As required

T H E O R Y :

(i) kirchoff’s voltage law

The algebraic sum of the voltage around any closed path is zero.

PROCE DU RE:

1. Connections are made as per the circuit diagram.2. Check your connections before switch on the supply.3. Vary the regulated supply.4. Measure the voltage using voltmeter.5. Note the readings in the tabulation.6. Compare the observation reading to theoretical value.

7

Circuit diagram

1. krichoff’s current law:

Kirchoff`s current law

1.0k 3.3k

5V 4.7 K

Practical measurement:

(0-20)mA (0-10)mA

+ A - + A -

4.7 K5V +

A (0-10)mA

-

Tabulation:

Voltage Total currentI(mA)

I1(mA) I2(mA)

8

Circuit diagram

Krichoff’s voltage law:

Kirchoff`s voltage law

1.0k 3.3k 2.7k

V1 V2 V3

5V

Practical measurement:

Practical measurement

1.0k 3.3k 2.7k

+ V

- + V - +

V -

5V (0-5)V (0-5)V (0-5)V

Tabulation:

Voltage(V)

V1(volts)

V2(volts)

V3(volts)

Calculation:

RESULT:

Thus the kirchoff’s current law and voltage law were verified.

9

10 .A. VERIFICAT ION OF THEVENIN ’ S T HE OREM

AIM:

To verify Thevenin’s theorem and to find the current flowing through the load resistance.

APPARATUS REQUIRED:


1

2

3

4

5

6

RPS

Resistor

Ammeter

voltmeter

Bread board

Connecting wires

(0-15)V

1KΩ,2.2KΩ,3.3KΩ2,7KΩ

(0-5)mA

(0-5)V

------

------

1

Each 1

1

1

1

As required

THEORY :

Th e v e n i n s t he o r e m :Any linear active network with output terminals can be replaced by a single voltage source Vth in series

with a single impedance Zth. Vth is the Thevenin`s voltage. It is the voltage between the terminals on opencircuit condition, Hence it is called open circuit voltage denoted by Voc. Zth is called Thevennin`s impedance. It is the driving point impedance at the terminals when all internal sources are set to zero too.

If a load impedance ZL is connected across output terminals, we can find the current through it IL = Vth/ (Zth + ZL).

PROCE DU RE:

1. Connections are made as per the circuit diagram.2. Check your connections before switch on the supply.3. Find the Thevenin’s voltage (or) open circuit voltage.4. Replace voltage source by internal resistor.5. Determine the Thevenin’s resistance.6. Find IL by using Thevenin’s formula.7. Compare the observation reading to theoretical value.8. switch off the supply9. Disconnect the circuit.

1010

Thevenin

Circuit diagram To find Rth

1.0k 3.3k 1.0k 3.3k

XMM1

5V 2.2k 2.7k R th 2.7k

To find Vth

1.0k 3.3k

To find IL

1.0k 3.3k

5V v 2.7k 5V2.2k

+ 2.7k

A (0-5)mA

-

Equiva1lent ciruitI

R th

V th

RL

2.2k

+A (0-5)mA

-

1111

Tabulation

Vth Rth IL(mA)

theoretical practical theoretical practical theoretical practical

Calculation:

R ES U LT: Thus the Thevenin’s theorem was verified.

Theoretical:Vth = Rth = IL =

Practical:Vth = Rth = IL =

1212

10. B. NORTO N’ S THE OER M

AIM:

To verify Norton’s theorem and to determine the current flow through the load resistance.


S.No Name of the apparatus

Range Quantity

1

2

3

4

5

RPS

Resistor

Ammeter

Bread board

Connecting wires

(0-15)V

10KΩ,5.6KΩ,8.2KΩ6KΩ

(0-10)mA,mc(0-5)mA,mc

------

------

1

Each 1

11

1

As required

No rto n’s t heore m:

Any linear active network with output terminals can be replaced by a single current source. Isc in parallel with a single impedance Zth. Isc is the current through the terminals of the active network when shorted. Zth is called Thevennin`s impedance.

Current through RL= Isc Zth/( Zth+ZL)

PROCE DU RE:

1. Connections are made as per the circuit diagram.2. Check your connections before switch on the supply.3. Find the Norton’s current (or) short circuit current in load resistance.4. Replace voltage source by internal resistor.5. Determine the equivalent’s resistance.6. Find IL by using Norton’s formula.7. Compare the observation reading to theoretical value.8. switch off the supply9. Disconnect the circuit.

R

1313

Circuit diagram

Norton

10K 8K

To find I sc

10K 8K

I sc+5V 4.7K 5.6K 5V 4.7K A (0-500)mA

-

To find R th

10K 8K

XMM1

Rt h

5V

To find IL

10K 8K

4.7K 5.6K+

4.7K A (0-500)mA-

Norton`s Equivalent circuit

Isc Rth

L =5.6K+

A (0-500)mA

-

1414

Tabulation:

Theoretical Practical

Isc Rth Isc Rth

Calculation:

R ES U LT: Thus the Norton’s theorem was verified.

Theoretical: Isc = Rth = IL =

Practical:Isc = Rth = IL =

1515

11 .SUPE R P OSITI ON T HE O REM

AIM:

To verify the superposition theorem and determine the current following through the load resistance.

APPARATUS REQUIRED:


1

2

3

5

6

RPS

Resistor

Ammeter

Bread board

Connecting wires

(0-15)V

1KΩ,220Ω,470Ω

(0-1)mA,mc(0-5)mA mc

------

------

1

Each 1

11

1

As required

Su pe rposit io n t heore m

In a linear circuit containing more than one source, the current that flows at any point or the voltage that exists between any two points is the algebraic sum of the currents or the voltages that would have been produced by each source taken separately with all other sources removed.

PR O C E D U R E :

1. Connections are made as per the circuit diagram.2. Check your connections before switch on the supply.3. Determine the current through the load resistance.4. Now one of the sources is shorted and the current flowing through the resistance IL measured by

ammeter.5. Similarly, the other source is shorted and the current flowing through the resistance IL measured by

ammeter.6. Compare the value obtained with the sum of I1&I2 should equal to I7. Compare the observation reading to theoretical value.8. switch off the supply9. Disconnect the circuit.

1616

Circuit diagramSuperposition

220 ohm 470 ohm

To find I1

w hen 12V source is acting

alone

220 ohm 470 ohm

1 K

+A (0-20)mA

-

TO find I When 10V source is acting alone2

220 ohm 470 ohm

To find I w hen two sources are acting

220 ohm 470 ohm

10 V

1 K+

12V 10 V

1 K+

A (0-20)mA-

A (0-20)mA-

Tabulation:

V(volt) I1(mA) I2(mA) I(mA)

V1 V2 theoretical practical theoretical practical theoretical practical

Calculation:

R ES U LT: Thus the superposition theorem was verified

1717

12. VERIFICATION OF MAXIMUM POWER TRANSFER THEOREM

AIM:To find the value of resistance RL in which maximum power is transferred to the load resistance.


Sl.No Name of the apparatus Range Quantity

1

2

3

4

5

6

Resistor

Ammeter

Bread board

Connecting wires

RPS

DRB

1KΩ,2.2 KΩ

(0-10) mA

-----

------

(0-30)V

(0-10)KΩ

1

1

1

As required

1

1

Max imum po w er t ra nsf er t heo r em:

Maximum power transfer to the load resistor occurs when it has a value equal to the resistance of the network looking back at it from the load terminals.

PR O C E D U R E :

1. Connections are given as per the circuit diagram.2. By giving various values of the resistance in DRB, note the ammeter

reading.3. Calculate the power and plot the power Vs resistance graph.4. Note the maximum power point corresponding resistance from the graph.

1818

Circuit diagramMax power transfer theorem

1.0k(0-10)mA

+ -A

Theoretical calculation

To find R th

1.0k

5V 2.2k RL 2.2k R th

Theoretical value:

Tabulation:

Resistance(RL)

Current I(mA) Power =I2RL

Theoretical calculation:

RESULT:

Thus the value of unknown resistance in which the maximum power is transferred to the load was found.

Theoretical load resistance = Practical load resistance = Maximum power =

1919

13 . VERIF IC ATION OF RECIPR OCITY T HE OR EM

A IM :

To verify Reciprocity theorem and to determine the current flow through the load resistance.



1

2

3

4

5

RPS

Resistor

Ammeter Bread

board Connecting

wires

(0-15)V

100Ω,470Ω,820Ω, 100Ω

(0-30) mA,

------

------

1

Each 1

1

1

As required

THEORY:

R ecipr o ci t y t h e o r e m In a linear, bilateral network a voltage source V volt in a branch gives rise 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.

PR O C E D U R E :

1. Connect the circuit as per the circuit diagram.2. Switch on the supply and note down the corresponding ammeter readings.3. Find ratio of input voltage to output current.4. Interchange the position of the ammeter and power supply. Note down the

Corresponding ammeter readings5. Verify the reciprocity theorem by equating the voltage to current ratio.

-

2020

CIRCUIT DIAGRAM

Reciprocity theorem

To find I

940 ohm 100 ohm 940 ohm 100 ohm

(0-30)V 470 ohm 100 0hm

+

A (0-30)mA 470 ohm 100 ohm

(0-30)V

To find I

940 ohm 100 0hm

(0-30)V470 ohm

100 ohm+

A (0-30)mA

-

Tabulation:Practical value :( circuit -I)

V(volt) I(mA) Z=V/I

2121

Practical value :( circuit -I)

V(volt) I(mA) Z=V/I

Calculation:

RESULT:

Thus the reciprocity theorem was verified

2222

14. A. F REQUENC Y RE SPO NSE OF SERIES RESO NANCE CIR CUI T

AIM:

To obtain the resonance frequency of the given RLC series electrical network.



1

2

3

4

5

6

7

Function generator

Resistor

Voltmeter

capacitor

Bread board

Connecting wires

Decade inductance box

0-2MHz

1KΩ,

(0-5) V

1µ F

-----

------

(0-100)mH

1

1

1

1

1

As required

1

FORM ULA USED :

Series resonance frequency F=1/ (2п √ (LC))

PR O C E D U R E: 1. Connections are made as per the circuit diagram.2. Vary the frequency of the function generator from 50 Hz to 20 KHz.3. Measure the corresponding value of voltage across the resistor R for series RLC circuit.4. Repeat the same procedure for different values of frequency.5. Tabulate your observation.6. Note down the resonance frequency from the graph.

2323

Circuit diagram: Series resonance

Fn. gen

1.0uF

C

50 mH

L

R 1.0k V (0-5)V

Tabulation:

Frequency (Hz) VR(volt)

Calculation:

RESULT:

Thus the resonance frequency of series RLC circuit is obtained.Practical value =

Theoretical value =

2424

14 .B. FREQUE NCY RE SPO NSE OF PAR ALLEL RESONAN CE C IR CUIT

A IM :

To obtain the resonance frequency of the given RLC parallel electrical network.

APPARATUS REQUIRED:


1

2

3

4

5

6

7

Function generator

Resistor

Voltmeter

capacitor

Bread board

Connecting wires


0-3MHz

1KΩ,

(0-5) V

1µ F

-----

------

(0-100)mH

1

1

1

1

1

As required

1

F O R M U LA U SE D :

Parallel resonance frequency F=1/ (2п √ (LC)


2525

Circuit diagramParallel resonance

Fn. genV (0-5)V R

1.0k C

1.0uFL50 mH

Tabulation:


Calculation:

R ES U LT :

Thus the resonance frequency of series RLC circuit is obtained.

Practical value = Theoretical value =

2626

15. TRANSIENT RESP ON SE OF R C AND RL CIRC UITS F OR D C I NPUT ’S.

AIM:

To construct RL & RC transient circuit and to draw the transient curves.

APPARATUS REQUIRED:

S.NO. NAME OFTHE

EQUIPMENT

RANGE TYPE QTY.

1. RPS (0-30)V DC 12. Ammeter (0-10)mA MC 13. Voltmeter (0-10)V MC 14. Resistor 10 KΩ - 3

5. Capacitor 1000 µ F - 16. Bread board - - 17. Connecting


THEORY:

Electrical devices are controlled by switches which are closed to connect supply to the device, or

opened in order to disconnect the supply to the device. The switching operation will change the current and

voltage in the device. The purely resistive devices will allow instantaneous change in current and voltage.

An inductive device will not allow sudden change in current and capacitance device will not allow

sudden change in voltage. Hence when switching operation is performed in inductive and capacitive devices,

the current & voltage in device will take a certain time to change from pre switching value to steady state value

after switching. This phenomenon is known as transient. The study of switching condition in the circuit is called

transient analysis.The state of the circuit from instant of switching to attainment of steady state is called

transient state. The time duration from the instant of switching till the steady state is called transient period. The

current & voltage of circuit elements during transient period is called transient response.

FORMULA:Time constant of RC circuit = RC

PROCEDURE:Connections are made as per the circuit diagram.

Before switching ON the power supply the switch S should be in off position

Now switch ON the power supply and change the switch to ON position.

2727

The voltage is gradually increased and note down the reading of ammeter and voltmeter for

each time duration in RC.In RL circuit measure the Ammeter reading.

Tabulate the readings and draw the graph of Vc(t)Vs t

CIRCUIT DIAGRAM:

RL CIRCUIT:

TABULATION:

S.NO. TIME(msec)

CHARGINGCURRENT (I) A

DISCHARGINGCURRENT (I) A


3030

MODEL GRAPH:

CIRCUIT DIAGRAM:

RC CIRCUIT:

MODEL GRAPH:

CHARGING DISCHARGING

3131

TABULATION:

CHARGING:

S.NO. TIME(msec)

VOLTAGEACROSS ‘C’

(volts)

CURRENTTHROUGH

‘C’ (mA)


TABULATION:

DISCHARGING:

S.NO. TIME(msec)


(volts)

CURRENTTHROUGH

‘C’ (mA)


RESULT:

Thus the transient response of RL & RC circuit for DC input was verified.

3333

8. TRANSIENT RESP ON SE OF R C AND RL CIRC UITS F OR D C I NPUT ’S.

AIM:

To construct RL & RC transient circuit and to draw the transient curves.

APPARATUS REQUIRED:

S.NO. NAME OFTHE

EQUIPMENT

RANGE TYPE QTY.

1. RPS (0-30)V DC 12. Ammeter (0-10)mA MC 13. Voltmeter (0-10)V MC 14. Resistor 10 KΩ - 3

5. Capacitor 1000 µ F - 16. Bread board - - 17. Connecting


THEORY:

Electrical devices are controlled by switches which are closed to connect supply to the device, or

opened in order to disconnect the supply to the device. The switching operation will change the current and

voltage in the device. The purely resistive devices will allow instantaneous change in current and voltage.

An inductive device will not allow sudden change in current and capacitance device will not allow

sudden change in voltage. Hence when switching operation is performed in inductive and capacitive devices,

the current & voltage in device will take a certain time to change from pre switching value to steady state value

after switching. This phenomenon is known as transient. The study of switching condition in the circuit is called

transient analysis.The state of the circuit from instant of switching to attainment of steady state is called

transient state. The time duration from the instant of switching till the steady state is called transient period. The

current & voltage of circuit elements during transient period is called transient response.

FORMULA:Time constant of RC circuit = RC

PROCEDURE:Connections are made as per the circuit diagram.

Before switching ON the power supply the switch S should be in off position

Now switch ON the power supply and change the switch to ON position.

3434

The voltage is gradually increased and note down the reading of ammeter and voltmeter for

each time duration in RC.In RL circuit measure the Ammeter reading.

Tabulate the readings and draw the graph of Vc(t)Vs t

CIRCUIT DIAGRAM:

RL CIRCUIT:

TABULATION:

S.NO. TIME(msec)

CHARGINGCURRENT (I) A

DISCHARGINGCURRENT (I) A


3030

MODEL GRAPH:

CIRCUIT DIAGRAM:

RC CIRCUIT:

MODEL GRAPH:

CHARGING DISCHARGING

3131

TABULATION:

CHARGING:

S.NO. TIME(msec)


(volts)

CURRENTTHROUGH

‘C’ (mA)


TABULATION:

DISCHARGING:

S.NO. TIME(msec)


(volts)

CURRENTTHROUGH

‘C’ (mA)


RESULT:

Thus the transient response of RL & RC circuit for DC input was verified.

3232

9. A. F REQUENC Y RE SPO NSE OF SERIES RESO NANCE CIR CUI T

AIM:

To obtain the resonance frequency of the given RLC series electrical network.



1

2

3

4

5

6

7

Function generator

Resistor

Voltmeter

capacitor

Bread board

Connecting wires


0-2MHz

1KΩ,

(0-5) V

1µ F

-----

------

(0-100)mH

1

1

1

1

1

As required

1

FORM ULA USED :

Series resonance frequency F=1/ (2п √ (LC))


3333

Circuit diagram: Series resonance

Fn. gen

1.0uF

C

50 mH

L

R 1.0k V (0-5)V

Tabulation:


Calculation:

RESULT:

Thus the resonance frequency of series RLC circuit is obtained.Practical value =

Theoretical value =

3434

9 .B. FREQUE NCY RE SPO NSE OF PAR ALLEL RESONAN CE C IR CUIT

A IM :

To obtain the resonance frequency of the given RLC parallel electrical network.

APPARATUS REQUIRED:


1

2

3

4

5

6

7

Function generator

Resistor

Voltmeter

capacitor

Bread board

Connecting wires


0-3MHz

1KΩ,

(0-5) V

1µ F

-----

------

(0-100)mH

1

1

1

1

1

As required

1

F O R M U LA U SE D :

Parallel resonance frequency F=1/ (2п √ (LC)


3535

Circuit diagramParallel resonance

Fn. genV (0-5)V R

1.0k C

1.0uFL50 mH

Tabulation:


Calculation:

R ES U LT :

Thus the resonance frequency of series RLC circuit is obtained.

Practical value = Theoretical value =

3636

10. FRE QU ENCY RE SPO NSE OF SINGLE T UNED C OU PLED CI RCUIT

AIM:

To determine the frequency response of a single tuned coupled circuits.

APPARATUS REQUIRED:

S.No. Name of the apparatus Range Quantity

1.

2.

Single tuned coupledcircuits.

Connecting wires

-

-

1

As required

THEORY:

When two coils are placed nearby and current passes through any one or both of the coils, they become

magnetically coupled. Then the coils are known as coupled coils. If the coils are part of a circuit, the circuit is

known as a coupled circuit. A Single tuned to resonance.

FREQUENCY RESPONSE OF SINGLE TUNED CIRCUITS:

The variation of the amplification factor or output voltage with frequency is called the frequency

response. It can be observed that the output voltage, current and amplification depend on mutual inductance at

resonance frequency. The maximum amplification depends on M and it occurs at resonance frequency.

Amplification factor is given by,

3737

Maximum amplification is given by :

PROCEDURE:

o Connections are given as per the circuit diagram.o Power supply is switched ON.o Input frequency is varied by AFO, corresponding input & output Voltage are

noted.o Graph is drawn between Frequency & Amplification factor.

CIRCUIT DIAGRAM:

TABULATION:Frequency (w)

in HzOutput Voltage

V0 (V)

Input voltageVi (V)

Amplification factor

38

Manual 2

Technology

Transcript of Manual 2