Capitol College

Spring Semester 2000



Circuit Theory: EE - 159

Lab Experiment #3

Mesh Analysis Verification






Andy Buettner

Instructor: Dr. Thomas

Due: March 21st, 2000

Received: ___________________

Objective


The objective of this lab is to determine the currents in a circuit with multiple sources using mesh analysis. Then, use mesh analysis to analyze a complex circuit. Lastly to compare the results with experimentally determined values.


Equipment Used


  1. Equipment used


    1. ET - 3100 Trainer #1517

    2. Fluke DMM ser. no: 31101554

    3. Lab kit EE - 159


  1. Components used


    1. 470 Ohm Resistor

    2. 680 Ohm Resistor

    3. 330 Ohm Resistor

    4. 1K Ohm Resistor

    5. 220 Ohm Resistor


Procedures


I) Part 1


1) Measure and record the individual resistances of each resistor

2) Assemble circuit from Diagram 1

3) Set voltages for both sides of the source

4) Measure voltages across each resistor


  1. Part 2


1) Measure the individual resistances of the resistors

2) Assemble the circuit in diagram 2

3) Set voltage on Trainer to 10 volts

4) Measure the voltages across each resistor


Results





Table 1

R1

R2
R3

R4
Measured Resistance

459 W

670 W

329 W

990 W

Measured Voltage

1.838V

2.685V

.510V

5.47V

Calculated Current

4.004ma

4.007ma

1.550ma

5.525ma

Determined Current

3.994ma

3.994ma

1.551ma

5.545ma


Table 2

R1

R2

R3

R4

R5

Measured Resistance

459 W

670 W

329 W

990 W

218 W

Measured Voltage

6.16V

2.960V

3.483V

6.48V

3.811V

Calculated Current

13.42ma

4.418ma

10.59ma

6.545ma

17.48ma

Determined Current

13.47ma

4.03ma

10.61ma

6.58ma

17.50ma


Diagram 1








Diagram 2



Answers to Lab Questions


  1. Q: Calculate the currents through each resistor using mesh analysis.

A: Answers in tables 1 & 2.


2) Q: Calculate the currents through each resistor using Ohm's law.

A: Answers in Tables 1 & 2.

3) Q: Compare results.

A: The results are nearly identical and in some cases are.


4) Q: Explain how a negative voltage can be made to be positive.

A: Reverse the poles of the volt - meter.


5) Q: The trainer can only produce differences of 15V. How can a difference of 30V be obtained?

A: By using both the positive and negative terminals instead of the ground terminal.

6) Q: What does the DMM read when the battery is low?

A: There is an icon in the top center that shows a battery with an X through it.


Conclusions


In order to complete this lab I used several aids to help me. First, to completely analyze the mesh analysis, I used my equation-solving program to perform the matrix math. Also, I used the found values of the resistors instead of the read ones to complete the mesh analysis. I found it interesting to find out exactly how little error was involved in this exercise.


Attachments


  1. Original Handout

  2. Original Data

  3. Calculations