Electrical Lab Experiments

To verify Nortons theorem for the given circuit

Sep 24 2023

AIM: To verify Norton’s theorem for the given circuit.

Apparatus Required:

S.No.	Name Of The Equipment	Range	Type	Quantity
1	Voltmeter	(0-20)V	Digital	1 NO
2	Ammeter	(0-20)mA	Digital	1 NO
3	RPS	0-30V	Digital	1 NO
4	Resistors	10K Ω,1K Ω		1 NO
		2.2Ω		1 NO
		330 Ω		1 NO
5	Breadboard	-	-	1 NO
6	DMM	-	Digital	1 NO
7	Connecting wires			Required Number

Circuit Diagram:

Given Circuit:

Practical Circuit Diagrams:

To Find IL

nortons-theorem-practical-circuit-diagram

To Find IN

To Find RN

Theory:

Norton’s Theorem Norton’s theorem states that in a lumped, linear network the equivalent circuit across any branch is replaced with a current source in parallel a resistance. Where the current is the Norton’s current which is the short circuit current though that branch and the resistance is the Norton’s resistance which is the equivalent resistance across that branch by replacing all the sources sources with their internal resistances.

For Source Current

For Norton's Current

Load Current through Load Resistor

IL = IN x [RN / (RN+ RL)]

Procedure:

Connect the circuit as per fig (1)
Adjust the output voltage of the regulated power supply to an appropriate value (Say 20V).
Note down the response (current, IL) through the branch of interest i.e. AB (ammeter reading).
Reduce the output voltage of the regulated power supply to 0V and switch-off the supply.
Disconnect the circuit and connect as per the fig (2).
Adjust the output voltage of the regulated power supply to 20V.
Note down the response (current, IN) through the branch AB (ammeter reading).
Reduce the output voltage of the regulated power supply to 0V and switch-off the supply.
Disconnect the circuit and connect as per the fig (3).
Connect the digital multimeter (DMM) across AB terminals and it should be kept in resistance mode to measure Norton’s resistance(RN).

Tabulation For Norton’s Theorem:

Theoritical Values	Practical Values
IN =	IN =
RN =	RN =
IL =	IL =

Results:

Viva Questions:

The internal resistance of a source is 2 Ohms and is connected with an External Load Of 10 Ohms Resistance. What is Rth?
In the above question if the voltage is 10 volts and the load is of 50 ohms. What is the load current and Vth? Verify IL?
If the internal resistance of a source is 5 ohms and is connected with an External Load Of 25 Ohms Resistance. What is Rth?
In the above question if the voltage is 20V and the load is of 50 Ohms. What is the load current and IN ? Verify IL ?