Transcript of 1 Clemson ECE Laboratories Pre-Labs for ECE 211 Created by Guneet Bedi on 09/03/2012 Last Updated:...
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- 1 Clemson ECE Laboratories Pre-Labs for ECE 211 Created by
Guneet Bedi on 09/03/2012 Last Updated: 12/15/2012
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- 2 Clemson ECE Laboratories ECE 211 - Electrical Engineering Lab
I Pre-labs for ECE 211 Guneet Bedi Created: 09/03/2012 Updated:
09/03/2012
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- 3 Clemson ECE Laboratories
- Slide 4
- 4 Introduction This laboratory course operates in co-ordination
with the companion lecture course, ECE 202, Electric Circuits 1. It
is intended to enhance the learning experience of the student in
topics encountered in ECE 202.
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- 5 Clemson ECE Laboratories Lab Objectives Through this lab,
students are expected to:- 1.Gain proficiency in the use of common
measuring instruments. 2.Compare theoretical predictions with
experimental results and explain any differences. 3.Develop verbal
and written communication skills through:- a.Maintenance of
succinct but complete laboratory notebooks and reports. b.Verbal
interchanges with the laboratory instructor and other
students.
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- 6 Clemson ECE Laboratories Lab Objectives contd 4.Enhance
understanding of the basic electric circuit analysis concepts
including:- a.Independent and dependent sources. b.Passive circuit
components (resistors, capacitors, inductors, and switches). c.Ohms
law, Kirchhoffs voltage law, and Kirchhoffs current law. d.Power
and energy relations. e.Thevenins theorem and Nortons theorem.
f.Superposition
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- 7 Clemson ECE Laboratories Student Responsibilities The student
is expected to be prepared for each lab. Active participation by
each student in lab activities is expected. The student is expected
to ask the teaching assistant any questions he/she may have. The
student should understand the concepts and procedure of each lab.
The student should remain alert and use common sense while
performing a lab experiment. He/she is also responsible for
maintaining a laboratory notebook. Students should report any
errors in the lab manual to the teaching assistant.
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- 8 Clemson ECE Laboratories Lab Policy Pre-Requisites:- MTHSC
108 and PHYS 122 Co-Requisites:- ECE 202 Attendance:- Attendance is
mandatory and any absence must be for a valid excuse and must be
documented. Late Instructor:- If the instructor is more than 15
minutes late, students may leave the lab. Pre-Lab:- Each lab has a
Preparation section that should be read and completed prior to each
lab.
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- 9 Clemson ECE Laboratories Lab Policy contd Lab Records:- The
student must keep all work in preparation of and obtained during
lab in an approved notebook and prepare a lab report on selected
experiments. Late Work:- All full lab write-ups are due two weeks
from the date lab is performed. Late work will NOT be accepted.
Final Exam:- The final exam will be given in lab on the last
meeting. This exam will be closed-book and closed-notes. Use of
calculator is permitted.
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- 10 Clemson ECE Laboratories Grading Policy The final grade is
determined using the following criteria:- Participation:- 10%
Attendance:- 10% Pre-Lab:- 20% Lab Reports:- 40% Final Exam:- 20%
Grade Scale:- A: 90%-100% B: 80%-89% C: 70%-79% D: 60%-69% F:
>All Program Files>>National Instrument">
- 38 Clemson ECE Laboratories NI ELVIS Instrument Launcher Launch
the Instrument Launcher by navigating to Start>>All Program
Files>>National Instruments>>NI ELVISmx>>NI
ELVISmx Instrument Launcher.
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- 39 Clemson ECE Laboratories NI ELVIS Instrument Launcher-DMM
1.Display 2.Modes 3.Connections 4.Acquisition mode 5.Help
6.Run/Stop 7.Null offset 8.Mode
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- 40 Clemson ECE Laboratories NI ELVIS Instrument Launcher-FGEN
1.Frequency Display 2.Waveform Selectors 3.Waveform Characteristics
4.Sweep Settings 5.Manual Mode 6.Signal Route 7.Sweep
- Slide 41
- 41 Clemson ECE Laboratories NI ELVIS Instrument Launcher-VPS
1.Voltage Display 2.Manual Mode 3.Output Voltage Controls 4.Sweep
Settings 1.Sweep
- Slide 42
- 42 Clemson ECE Laboratories Procedure-Getting Started 1.Turn on
computer. 2.Turn on NI-ELVIS power switch (right corner on the
back). 3.Turn on the NI-ELVIS Prototyping Board Power switch (at
upper right corner, on top). 4.Launch NI-ELVISMX INSTRUMENTS
program. 5.Launch the NI-ELVIS DMM instrument. 6.Launch the
NI-ELVIS VPS (Variable Power Supply) instrument. 7.Arrange the
instruments on the computer screen for your convenience. 8.Set DMM
to measure DC Volts. Specify the range to be 60V.
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- 43 Clemson ECE Laboratories Procedure-NULL OFFSET for Voltmeter
Electrical drift sometimes causes shifts in the ZERO point
indicated by measurement instruments. To eliminate the shift, the
NI-ELVIS provides a NULL OFFSET function that subtracts the value
indicated at the instant NULL OFFSET is turned on. To set the
voltmeters NULL OFFSET: 1.Plug leads into the DMM V and COM jacks.
2.Clip the leads together, let the voltage reading stabilize.
3.Turn on Null Offset.
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- 44 Clemson ECE Laboratories Procedure-DC Resistance of DMM
Voltmeter Set the VPS Supply + voltage to +10.00 Volts. STOP the
VPS. Set up the circuit as shown in figure. Use the NI-ELVIS DMM
for the voltmeter and the VPS for the power supply. Set the
resistor R to 0 by shorting the resistors leads. RUN the VPS and
record the voltage indicated by the meter. Remove the short across
R.
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- 45 Clemson ECE Laboratories Procedure-DC Resistance of DMM
Voltmeter contd Increase the resistance R so that the meter reading
drops by one half of the original value. Record the final
resistance R and measured voltage. STOP the VPS. Use the DMM
ohmmeter to measure the actual resistance R. Record the measured
value. From these readings, use voltage division to calculate R Vi,
the equivalent internal resistance of the voltmeter.
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- 46 Clemson ECE Laboratories Procedure-DC Resistance of DMM
Ammeter Set the VPS Supply + voltage to +10.00 Volts. RUN the VPS
and measure the actual voltage using the DMM voltmeter. Record the
actual voltage. STOP the VPS. To use the DMM as an ammeter, move
the DMM cables to A and COM and switch the DMM to measure DC Amps.
Set up the circuit as shown in figure. Use the NI-ELVIS DMM for the
ammeter and the VPS for the power supply.
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- 47 Clemson ECE Laboratories Procedure-DC Resistance of DMM
Ammeter contd Set the resistor R to 1 M resistance. RUN the VPS.
Record the resistance R and the current indicated by the ammeter.
Adjust R to 100k. Record the resistance R and the current indicated
by the ammeter. Continue to decrease the resistance R until the
ammeter reading drops to one half of the original value. Record the
final resistance R and measured current. Use the DMM ohmmeter to
measure the actual final resistance R. From these readings, use
current division to calculate R Ai, the equivalent internal
resistance of the ammeter.
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- 48 Clemson ECE Laboratories Procedure-Output Resistance of VPS
Supply + Set the VPS Supply + voltage to +0.5 Volts. Use the DMM to
measure the actual voltage. Record the actual voltage. Construct
the circuit shown in figure.
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- 49 Clemson ECE Laboratories Procedure-Output Resistance of VPS
Supply + contd Adjust the resistor R to 10k. RUN the VPS. Record
the resistance R and the measured voltage. Adjust the resistance R
so that the meter reading drops to one half of the original value.
Record the R and V values. From these readings, use voltage
division to determine R VPS. Where,
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- 50 Clemson ECE Laboratories Procedure-Output Resistance of FGEN
Construct the circuit shown in figure. Set the FGEN to output a
sine wave with p-p amplitude of 1.41V and frequency 100 Hz. Set the
DMM to measure AC Volts. Keep in mind that the voltmeters display
shows the value of RMS voltage, where for a sinusoidal
waveform,
- Slide 51
- 51 Clemson ECE Laboratories Procedure-Output Resistance of FGEN
contd Adjust the resistor R to 100 k. RUN the FGEN. Record the
resistance and the measured voltage. Adjust the resistance R so
that the meter reading drops to one half of the original value.
Record the R and V values. From these readings, use voltage
division to determine RFGEN, the equivalent internal resistance of
the Function Generator. Where,
- Slide 52
- 52 Clemson ECE Laboratories Lab 2-Student Tasks Students are
required to submit a lab report on this experiment. Students MUST
strictly adhere to the format as described in the lab manual. For
the Questions section of the lab report, the students are required
to solve the problems given as a part of Probing Further section of
this lab in the manual. Your report is due in TWO WEEKS from
today.
- Slide 53
- 53 Clemson ECE Laboratories Preparations for Next Week Read the
introductory material in the ECE 202 textbook describing the
passive sign convention for circuit elements. Review the lab manual
section Use of Laboratory Instruments. Calculate the values of
voltage, current, and power absorbed/delivered for each circuit
element in Figure 3.1 (i.e. do Part 0 of the Procedure). Sketch in
your lab notebook the circuit diagrams to be used in each part of
the procedure and have a table prepared for each part in order to
record data.
- Slide 54
- 54 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. Otago University
Electronics Group-NI ELVIS II Orientation Manual.
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- 55 Clemson ECE Laboratories
- Slide 56
- 56 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab III Pre-labs for ECE 211 Guneet Bedi Created: 09/13/2012
Updated: 09/16/2012
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- 57 Clemson ECE Laboratories
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- 58 Clemson ECE Laboratories Introduction Voltage and current
values may be used to determine the power consumed (or provided) by
an electrical circuit. Electric power consumption is a very
important factor in all electrical applications, ranging from
portable computers to megawatt industrial complexes. Thus, an
understanding of power and how it is measured is vital to all
engineers.
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- 59 Clemson ECE Laboratories Electric Charge-A Brief Review The
charge is bipolar, i.e. electrical effects are described in terms
of positive and negative charges. The electric charge exists in
discrete quantities, which are integral multiples of the electronic
charge, 1.602210 -19 C. Electrical effects are attributed to both
the separation of charge and charges in motion.
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- 60 Clemson ECE Laboratories Voltage Whenever positive and
negative charges are separated, energy is expended. Voltage is the
energy per unit charge created by the separation. It can be
expressed in differential form as: where, v=voltage in volts
w=energy in joules q=charge in coulombs
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- 61 Clemson ECE Laboratories Current Electric current is defined
as the rate of charge flow. It can be expressed in differential
form as: where i=current in amperes q=charge in coulombs t=time in
seconds
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- 62 Clemson ECE Laboratories Power Power is the time rate of
expending or absorbing energy. Mathematically, energy per unit time
can be expressed in differential form as: where p=power in watts
w=energy in joules t=time in seconds
- Slide 63
- 63 Clemson ECE Laboratories Power in terms of Voltage &
Current so, where p=power in watts v=voltage in volts i=current in
amperes
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- 64 Clemson ECE Laboratories Passive Sign Convention Whenever
the reference direction for the current in an element is in the
direction of the reference voltage drop across the element (as
shown in figure), use a positive sign in any expression that
relates the voltage to the current. Otherwise, use a negative
sign.
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- 65 Clemson ECE Laboratories Use of Laboratory
Instruments-Ammeter Ammeters are used to measure the flow of
electrical current in a circuit. For ammeters, it is important that
their internal resistance be very small (ideally near zero) so they
will not constrict the flow of current. Ammeters must always be
connected in series in a circuit, never in parallel with a voltage
source.
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- 66 Clemson ECE Laboratories Use of Laboratory
Instruments-Voltmeter Voltmeters are used to measure the potential
difference between two points. Since the voltmeter should not
affect the circuit, the voltmeters have very high (ideally
infinite) impedance.
- Slide 67
- 67 Clemson ECE Laboratories Lab Objective By the end of this
lab, the student should know:- o How to make DC measurements of
voltages and currents. o How to determine power
dissipation/delivery for circuit elements, branches, and various
combinations of elements and branches.
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- 68 Clemson ECE Laboratories Equipment Needed NI-ELVIS Series II
workstation Two 510 Resistors One 1k Resistor
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- 69 Clemson ECE Laboratories Procedure-Theoretical Calculation
of Voltage, Current & Power For the circuit given in figure,
calculate the voltages across and currents through each circuit
element. Using these values, determine the power absorbed or
delivered by each circuit element.
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- 70 Clemson ECE Laboratories Procedure-Experimental Circuit
Voltage Measurements Set up the circuit in figure. Adjust the
output of the DC power supply to 10V. Using the DMM function in the
NI-ELVIS workstation measure the voltage across each individual
circuit element. For each measured voltage, determine the percent
difference from the theoretical value.
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- 71 Clemson ECE Laboratories Procedure-Experimental Circuit
Current Measurements Set up the circuit in figure. Adjust the
output of the DC power supply to 10V. Using the DMM function in the
NI-ELVIS workstation measure the current through each individual
circuit element. For each measured current, determine the percent
difference from the theoretical value.
- Slide 72
- 72 Clemson ECE Laboratories Procedure-Experimental Circuit
Power Calculation Using your experimental voltage and current
measurement data, calculate the power absorbed or delivered by each
circuit element. Compare this power obtained with the values
obtained through theoretical circuit analysis. Calculate the
percent difference from the theoretical values.
- Slide 73
- 73 Clemson ECE Laboratories Lab 3-Student Tasks Students are
required to solve the Probing Further section, given in the lab
manual, in their laboratory notebooks. Lab notebooks are due on the
same day as your report for lab 2.
- Slide 74
- 74 Clemson ECE Laboratories Preparations for Next Week
Calculate the voltages and currents for each resistor shown in the
circuit of Figure 4.1 in your lab manual (i.e. do Part 0 of the
Procedure).
- Slide 75
- 75 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. Electric Circuits 8 th
Edition by James W. Nilsson & Susan A. Riedel.
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- 76 Clemson ECE Laboratories
- Slide 77
- 77 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab IV Pre-labs for ECE 211 Guneet Bedi Created: 09/24/2012
Updated: 09/24/2012
- Slide 78
- 78 Clemson ECE Laboratories
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- 79 Clemson ECE Laboratories Introduction B2 Spice v5 is an
integrated circuit design, simulation, and analysis software It
contains a mixed mode simulator based partly on the Berkeley SPICE
simulator and partly on the Georgia Tech XSPICE simulator B2 Spice
v5 is an application with two separate subprograms: the B2 Spice
main program, and the Database Editor It allows you to perform
realistic simulations on your circuit without the need of any
physical component or any expensive test equipment
- Slide 80
- 80 Clemson ECE Laboratories Lab Objective This lab should give
the student a basic understanding of how to use B2 Spice to
simulate circuit operating conditions. After this lab, the student
should be able to use B2 Spice to solve or check basic circuit
problems.
- Slide 81
- 81 Clemson ECE Laboratories Equipment Needed A computer with B2
Spice loaded and ready to use.
- Slide 82
- 82 Clemson ECE Laboratories Procedure-Theoretical Calculation
of Voltage & Current For the circuit given in figure, calculate
the voltages across and currents through each resistor.
- Slide 83
- 83 Clemson ECE Laboratories Procedure-Opening Software &
Creating New Project Double click on B2SpiceV5 shortcut icon on
desktop The following window will appear
File->New->Project(Check Schematic & Enter Project
Name)->Ok
- Slide 84
- 84 Clemson ECE Laboratories Procedure-Placing Resistors Common
parts->Resistor(simple)(R) Place resistor as desired on the
workspace Double click on the resistor placed to modify its default
parameters Right click on the resistor placed for more options(e.g.
rotate clockwise)
- Slide 85
- 85 Clemson ECE Laboratories Procedure-Placing Voltage Source
Common parts->Voltage Source(V) Place the voltage source as
desired on the workspace Double click on the voltage source placed
to modify its default parameters Right click on the voltage source
placed for more options(e.g. rotate clockwise)
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- 86 Clemson ECE Laboratories Procedure-Placing Ammeter/Voltmeter
Common parts->Ammeter(1)/Voltmeter(2) (Horizontal/Vertical)
Place the ammeter/voltmeter as desired on the workspace Double
click on the ammeter/voltmeter placed to modify its default
parameters Right click on the ammeter/voltmeter placed for more
options(e.g. rotate clockwise)
- Slide 87
- 87 Clemson ECE Laboratories Procedure-Placing Ground Common
parts->Ground(0) Place the ground as desired on the workspace
Ground default parameters cannot be changed Right click on the
ground placed for more options(e.g. rotate clockwise)
- Slide 88
- 88 Clemson ECE Laboratories Procedure-Connecting Circuit
Components On clicking the draw circuit lines symbol, one can draw
circuit lines to connect circuit components together To discontinue
drawing the circuit line press esc Press to draw circuit lines
- Slide 89
- 89 Clemson ECE Laboratories Procedure-Running Simulations After
setting up the circuit and placing the meters in the proper
positions, press Run to simulate the circuit To stop simulation,
click Simulation->Stop and Reset Run Pause Simulation
- Slide 90
- 90 Clemson ECE Laboratories Test Circuit 1
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- 91 Clemson ECE Laboratories Test Circuit 2
- Slide 92
- 92 Clemson ECE Laboratories Test Circuit 3 How does V across
& I through each resistor vary with the given combinations of
resistor values?
- Slide 93
- 93 Clemson ECE Laboratories Lab 4-Student Tasks Students are
required to solve the Probing Further section, given in the lab
manual, in their laboratory notebooks. Lab notebooks are due on the
same day as your report for lab 2.
- Slide 94
- 94 Clemson ECE Laboratories Preparations for Next Week Read the
material in the textbook that describes Kirchhoff's Voltage Law,
Kirchhoff's Current Law, voltage division, current division, and
equivalent resistance combinations. Before coming to class, analyze
each circuit and determine the theoretical values that should be
obtained during the lab. Verify your calculations by performing B2
Spice simulations for each circuit. Record both your calculations
and simulation results in your laboratory notebook.
- Slide 95
- 95 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. B2Spice Version 5
Users Manual by Manual by Thien Nguyen, Christopher Hsiong and Jon
Engelbert 1996 - 2005, Beige Bag Software, Inc.
- Slide 96
- 96 Clemson ECE Laboratories
- Slide 97
- 97 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab V Pre-labs for ECE 211 Guneet Bedi Created: 10/01/2012 Updated:
10/01/2012
- Slide 98
- 98 Clemson ECE Laboratories
- Slide 99
- 99 Clemson ECE Laboratories Introduction An understanding of
the basic laws of electrical voltages and currents is essential to
electrical engineering. Circuit analysis is dependent upon knowing
the nature of the laws governing voltage and current
characteristics. This lab studies Kirchhoff's Voltage Law,
Kirchhoff's Current Law, voltage division, current division, and
equivalent resistance.
- Slide 100
- 100 Clemson ECE Laboratories Series Equivalent Resistance
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- 101 Clemson ECE Laboratories Parallel Equivalent
Resistance
- Slide 102
- 102 Clemson ECE Laboratories Voltage-Divider Circuit
- Slide 103
- 103 Clemson ECE Laboratories Current-Divider Circuit
- Slide 104
- 104 Clemson ECE Laboratories Kirchhoffs Current Law The
algebraic sum of all the currents at any node in a circuit equals
zero. Using the convention that currents leaving the node are
considered positive and that entering the nodes are considered
negative, the above circuit yields the four equations.
- Slide 105
- 105 Clemson ECE Laboratories Kirchhoffs Voltage Law The
algebraic sum of all the voltages around any closed path in a
circuit equals zero. Here we elect to trace the closed path
clockwise, assigning a positive algebraic sign to voltage drops.
Starting at node d leads to the expression:
- Slide 106
- 106 Clemson ECE Laboratories Lab Objective By the end of this
lab, the student should understand KVL, KCL, voltage division,
current division, and equivalent resistance combinations.
- Slide 107
- 107 Clemson ECE Laboratories Equipment Needed NI-ELVIS
workstation Resistance substitution box Individual resistors (510,
1k (2), 1.5k, 2k (2), 3k, 3.9k, 4.3k, 5.1k)
- Slide 108
- 108 Clemson ECE Laboratories Procedure-Equivalent Resistance
Set up the circuit as shown in figure. Adjust the output of the DC
power supply to 10V. Measure and record the total current into the
circuit. Using the measured current and voltage, determine the
equivalent resistance of the parallel components in the circuit.
Replace the resistors with a resistance substitution box set to the
equivalent resistance and measure the current as before. Compare
the experimentally determined equivalent resistance to the
theoretical value.
- Slide 109
- 109 Clemson ECE Laboratories Procedure-Current Division &
Kirchhoff's Current Law (KCL) Set up the circuit as shown in
figure. Adjust the output of the DC power supply to 10V. Begin with
R 2 =510 and measure the currents I 1, I 2 and I 3. Repeat with R 2
=1k, 2k, 3k, 4.3k and 5.1k. Compare the measured currents to those
calculated using current divider relation. Determine whether or not
each set of measurements agrees with KCL.
- Slide 110
- 110 Clemson ECE Laboratories Procedure-Voltage Division Set up
the circuit as shown in figure. Adjust the output of the DC power
supply to 10V. Begin with R=510 and measure the voltage across each
resistor. Repeat with R=1k, 2k, 3k, 4.3k and 5.1k. Compare the
measured voltages to those calculated using the voltage divider
relation.
- Slide 111
- 111 Clemson ECE Laboratories Procedure-Kirchhoffs Voltage Law
(KVL) (Single Loop) Set up the circuit as shown in figure. Adjust
the output of the DC power supply to 10V. Measure the voltage
across each component. Compare the measured voltages to those
calculated using the voltage divider relation. Determine whether or
not your measurements agree with KVL.
- Slide 112
- 112 Clemson ECE Laboratories Procedure-Kirchhoffs Voltage Law
(KVL) (Multiple Loops) Set up the circuit as shown in figure.
Adjust the output of the DC power supply to 10V. Measure the
voltage across each component in loop 1. Repeat for loop 2 and 3.
Compare your measured values with the terms in the KVL equation
written for each loop. Determine whether or not your measurements
agree with KVL.
- Slide 113
- 113 Clemson ECE Laboratories Lab 5-Student Tasks Students are
required to submit a lab report on this experiment. Students MUST
strictly adhere to the format as described in the lab manual. For
the Questions section of the lab report, the students are required
to solve the problems given as a part of Probing Further section of
this lab in the manual. Your report is due in TWO WEEKS from
today.
- Slide 114
- 114 Clemson ECE Laboratories Preparations for Next Week Read
the material in the textbook that describes Thevenin's equivalence
theorem and maximum power transfer.
- Slide 115
- 115 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. Electric Circuits 8 th
Edition by James W. Nilsson & Susan A. Riedel.
- Slide 116
- 116 Clemson ECE Laboratories
- Slide 117
- 117 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab VI Pre-labs for ECE 211 Guneet Bedi Created: 10/09/2012
Updated: 10/09/2012
- Slide 118
- 118 Clemson ECE Laboratories
- Slide 119
- 119 Clemson ECE Laboratories Introduction This lab focuses on
the Thevenin equivalent and maximum power transfer theorems.
Complex circuits are often replaced with their Thevenin equivalent
to simplify analysis. Maximum power transfer is also an important
concept which allows the designer to determine an optimal design
when power is a constraint.
- Slide 120
- 120 Clemson ECE Laboratories Thevenin Equivalent Circuit
Thevenin equivalent circuit is an independent voltage source V Th
in series with a resistor R Th, which replaces an interconnection
of sources and resistors. This series combination of V Th and R Th
is equivalent to the original circuit in the sense that, if we
connect the same load across the terminals a, b of each circuit, we
get the same volt- age and current at the terminals of the load.
This equivalence holds for all possible values of load
resistance.
- Slide 121
- 121 Clemson ECE Laboratories Thevenin Equivalent Circuit contd
To calculate the Thevenin voltage V Th, we simply calculate the
open- circuit voltage in the original circuit. If we place a short
circuit across the terminals a, b of the Thevenin equivalent
circuit, the short-circuit current directed from a to b is This
short-circuit current must be identical to the short-circuit
current that exists in a short circuit placed across the terminals
a, b of the original network. Thus the Thevenin resistance is the
ratio of the open-circuit voltage to the short-circuit
current.
- Slide 122
- 122 Clemson ECE Laboratories Maximum Power Transfer Maximum
power transfer occurs when the load resistance equals the Thevenin
resistance i.e. R L =R Th The maximum power delivered to R L
is
- Slide 123
- 123 Clemson ECE Laboratories Lab Objective By the end of this
lab, the student should be able to verify Thevenin's equivalence
theorem and the concept of maximum power transfer.
- Slide 124
- 124 Clemson ECE Laboratories Equipment Needed NI-ELVIS
workstation Resistance substitution box Individual resistors (220,
330, 680, 1k)
- Slide 125
- 125 Clemson ECE Laboratories Procedure-Thevenins Theorem Set up
the circuit as shown in figure. Adjust the output of the DC power
supply to 10V. Measure the open circuit voltage between nodes A and
B. Now connect the ammeter between nodes A and B and measure the
short circuit current between nodes A and B. Using these
measurements, determine the Thevenin equivalent circuit. Set up the
newly determined Thevenin equivalent circuit and verify that this
circuit has the same open circuit voltage and short circuit current
as the previous circuit.
- Slide 126
- 126 Clemson ECE Laboratories Procedure-Maximum Power Transfer
Theorem Use the Thevenin equivalent circuit developed in Part 1.
For a resistance substitution box R L between nodes A and B,
measure the current through and voltage across R L for R L =0.
Repeat for R L =100, 120 500 (in 20 increments). Determine the
power dissipated by the resistor for each value of R L. Plot Power
vs. Resistance. At which value is the power a maximum?
- Slide 127
- 127 Clemson ECE Laboratories Lab 6-Student Tasks Students are
required to solve the Probing Further section, given in the lab
manual, in their laboratory notebooks. Lab notebooks are due on the
same day as your report for lab 5.
- Slide 128
- 128 Clemson ECE Laboratories Preparations for Next Week Review
'XYZs of Oscilloscopes', available at: www.tek.com (60+ pages). Be
familiar with the following: o Voltage scaling (Volts/division) o
Time base (seconds/division) o Input coupling o Triggering o
Measurement probes
- Slide 129
- 129 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. Electric Circuits 8 th
Edition by James W. Nilsson & Susan A. Riedel.
- Slide 130
- 130 Clemson ECE Laboratories
- Slide 131
- 131 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab VII Pre-labs for ECE 211 Guneet Bedi Created: 10/19/2012
Updated: 10/19/2012
- Slide 132
- 132 Clemson ECE Laboratories
- Slide 133
- 133 Clemson ECE Laboratories Introduction Oscilloscopes are
indispensable tools for anyone designing, manufacturing or
repairing electronic equipment. The digital oscilloscope allows the
engineer to examine time varying waveforms to determine the
magnitude, frequency, phase angle, and other waveform
characteristics which depend upon the interaction of circuit
elements with the sources driving them. The usefulness of an
oscilloscope is not limited to the world of electronics. With the
proper sensor, an oscilloscope can measure all kinds of
phenomena.
- Slide 134
- 134 Clemson ECE Laboratories The Oscilloscope The oscilloscope
is basically a graph-displaying device. The graph shows how signals
change over time. The vertical (Y) axis represents voltage and the
horizontal (X) axis represents time. The intensity or brightness of
the display is sometimes called the Z axis, as shown in
figure.
- Slide 135
- 135 Clemson ECE Laboratories Waveforms A waveform is a graphic
representation of a wave. Waveform shapes reveal a great deal about
a signal. Any time you see a change in the height of the waveform,
you know the voltage has changed. Any time there is a flat
horizontal line, you know that there is no change for that length
of time. Straight, diagonal lines mean a linear change rise or fall
of voltage at a steady rate. Sharp angles on a waveform indicate
sudden change.
- Slide 136
- 136 Clemson ECE Laboratories Waveform Measurements-Frequency
& Period If a signal repeats, it has a frequency. The frequency
is measured in Hertz (Hz) and equals the number of times the signal
repeats itself in one second, referred to as cycles per second. A
repetitive signal also has a period, which is the amount of time it
takes the signal to complete one cycle. Period and frequency are
reciprocals of each other,
- Slide 137
- 137 Clemson ECE Laboratories Waveform Measurements-Voltage
Voltage is the amount of electric potential, or signal strength,
between two points in a circuit. Usually, one of these points is
ground, or zero volts, but not always. One may measure the voltage
from the maximum peak to the minimum peak of a waveform, referred
to as the peak-to-peak voltage.
- Slide 138
- 138 Clemson ECE Laboratories Waveform Measurements-Amplitude
Amplitude refers to the amount of voltage between two points in a
circuit. Amplitude commonly refers to the maximum voltage of a
signal measured from ground, or zero volts. The waveform shown in
figure has an amplitude of 1 V.
- Slide 139
- 139 Clemson ECE Laboratories Waveform Measurements-Phase The
voltage level of sine wave is based on circular motion. Given that
a circle has 360, one cycle of a sine wave has 360. Phase shift
describes the difference in timing between two otherwise similar
signals. The waveform in figure labeled current is said to be 90
out of phase with the waveform labeled voltage, since the waves
reach similar points in their cycles exactly 1/4 of a cycle apart
(360/4 = 90).
- Slide 140
- 140 Clemson ECE Laboratories Controls of an Oscilloscope The
front panel of an oscilloscope is divided into three main sections:
o Vertical: The attenuation or amplification of the signal. Use the
volts/div control to adjust the amplitude of the signal to the
desired measurement range. o Horizontal: The time base. Use the
sec/div control to set the amount of time per division represented
horizontally across the screen. o Trigger: The triggering of the
oscilloscope. Use the trigger level to stabilize a repeating
signal.
- Slide 141
- 141 Clemson ECE Laboratories Probes Even the most advanced
instrument can only be as precise as the data that goes into it. A
probe functions in conjunction with an oscilloscope as part of the
measurement system. Precision measurements start at the probe tip.
The right probes matched to the oscilloscope and the device-under
test (DUT) not only allow the signal to be brought to the
oscilloscope cleanly, they also amplify and preserve the signal for
the greatest signal integrity and measurement accuracy.
- Slide 142
- 142 Clemson ECE Laboratories Probe Types Passive Probes Active
& Differential Probes Logic Probes Specialty Probes
- Slide 143
- 143 Clemson ECE Laboratories NI-ELVIS Series II Workstation-
Additional Features Oscilloscope (Scope) Connectors (Input): o CH 0
BNC Connector: The input for channel 0 of the oscilloscope. o CH 1
BNC Connector: The input for channel 1 of the oscilloscope. SYNC
(Output): o 5V TTL signal synchronized to the FGEN signal. o This
signal is most used as a trigger signal for the oscilloscope.
- Slide 144
- 144 Clemson ECE Laboratories 1.Scope Graph 2.Channel Settings
3.Probe & Coupling 4.Volts/Div (Vertical sensitivity) &
Vertical Position 5.Trigger 6.Log 7.Timebase (Horizontal
Sensitivity) 8.Display Measurement 9.Cursor Settings NI ELVIS
Instrument Launcher- Scope (Oscilloscope)
- Slide 145
- 145 Clemson ECE Laboratories Lab Objective By the end of the
lab the student should be familiar with the controls of a digital
oscilloscope and be able to use the instrument to observe periodic
waveforms.
- Slide 146
- 146 Clemson ECE Laboratories Equipment Needed NI-ELVIS
workstation 100 resistor 1k resistor
- Slide 147
- 147 Clemson ECE Laboratories Procedure-Basic Setup Connect a
cable with BNC fitting to the BNC jack for CH 0 of the oscilloscope
on the left side of the NI-ELVIS II. Connect the cables red lead to
the FGEN output; connect the cables black lead to GROUND. Set the
function generator to output a 100Hz sine wave with amplitude = 3.0
VPP and DC offset = 0V. Open the oscilloscope window in the
NI-ELVIS software. ENABLE the display for Channel 0. RUN the
function generator and the oscilloscope. Turn on the prototype
board. Record the measured values for RMS voltage, peak-to-peak
voltage, and waveform frequency. Sketch the displayed waveform in
your laboratory notebook. Compare your measurements with the
expected values based on the function generator output.
- Slide 148
- 148 Clemson ECE Laboratories Procedure-Source Control Connect
CH 0 to SYNC (adjacent to FGEN). Sketch this waveform in your
laboratory notebook. Reconnect CH 0 to FGEN. Change the function
generator output to a square wave. Record the displayed waveform in
your laboratory notebook. Measure the peak-to peak output voltage.
Repeat this measurement for a triangular wave.
- Slide 149
- 149 Clemson ECE Laboratories Procedure-Voltage Scaling Reset
the function generator to output a sine wave. Vary the vertical
scale control for Channel 0 using either the control knob or
pull-down menu. Record the effect that this control has on the
displayed waveform. Set the control to 500mV/div. Measure the
peak-to-peak magnitude of the displayed waveform by counting
(estimate) the number of peak-to-peak divisions and multiplying by
the vertical scale. Compare this result with the measurement given
by the oscilloscope.
- Slide 150
- 150 Clemson ECE Laboratories Procedure-Voltage Offset
Manipulation Vary the vertical position control in the oscilloscope
and record the effects in your laboratory notebook, noting any
changes in the measured RMS voltage. Return the offset to zero and
add a DC offset of 0.5V to the function generator output. Record
the effects in your laboratory notebook, noting any changes in the
measured RMS voltage.
- Slide 151
- 151 Clemson ECE Laboratories Procedure-Time Scaling Return the
DC offset in the function generator to 0V. Using either the
timebase dial or pulldown menu, adjust the timebase of the
oscilloscope display to the fastest setting (5s/div). Record the
effect that this setting has on displayed measurements for the
waveform. Gradually increase the timebase through each available
setting until the slowest setting has been reached (200ms/div).
Record the effect that this control has on the measurement of
voltage and frequency. Return the timebase to a setting where 1-3
full cycles of the output sine wave is viewable. Set the
Acquisition Mode to RUN ONCE and press RUN to capture a single
sweep of the output waveform. Measure the period of the waveform by
counting (estimate) the number of time divisions for a single cycle
and multiplying by the time scale. Compare this measurement to the
inverse of the frequency measured by the oscilloscope.
- Slide 152
- 152 Clemson ECE Laboratories Procedure-Triggering/Synch
Function Return the screen update to 'RUN'. Adjust the triggering
pull-down menu to edge and record the oscilloscope response. Vary
the function generator peak amplitude to verify that the
oscilloscope is continuing to update the display in this mode of
operation.
- Slide 153
- 153 Clemson ECE Laboratories Procedure-Cursor Function Set the
function generator to output a 100Hz sine wave with peak amplitude
= 3.0 VPP and DC offset = 0V. Return the triggering function to
'Immediate'. Display a single screen update of between 1-3 cycles
of the output function. Switch the cursors function on and drag the
cursors to appropriate points on the waveform to measure the period
of the sine wave. Then adjust the cursors to measure the
peak-to-peak voltage of the sine wave. Compare these measurements
to those expected based on the function generator's output
settings.
- Slide 154
- 154 Clemson ECE Laboratories Procedure-Test Circuit Connect the
voltage divider circuit shown in figure. Set the function generator
to output a 1kHz sine wave with amplitude 2V p-p and DC offset = 0.
Display the function generator output on channel 0 of the
oscilloscope and the voltage across the 100 resistor on channel 1.
Display and measure these voltages simultaneously. Measure the
period of both waveforms using the cursor function. + -
- Slide 155
- 155 Clemson ECE Laboratories Procedure-Test Circuit contd
Sketch the waveforms in your laboratory notebook and record your
settings for Volts/div and seconds/div. Compare your voltage
measurements with theoretical calculations based on the voltage
divider equation. Compare your waveform period measurement with the
theoretical value obtained from the input frequency. + -
- Slide 156
- 156 Clemson ECE Laboratories Procedure-Test Circuit contd
Reverse the polarity for the output voltage measurement on Channel
1. Repeat your voltage and period measurements. Sketch the
resulting waveforms in your laboratory notebook. Record your
settings for Volts/div and seconds/div. - +
- Slide 157
- 157 Clemson ECE Laboratories Lab 7-Student Tasks Students are
required to solve the Probing Further section, given in the lab
manual, in their laboratory notebooks.
- Slide 158
- 158 Clemson ECE Laboratories Preparations for Next Week Read
Appendix C, Fundamentals of Statistical Analysis. Become familiar
with the following concepts: o Mean o Standard deviation o Variance
and o The formulas used for calculating these quantities.
- Slide 159
- 159 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. XYZs of
Oscilloscopes-Primer by Tektronix Otago University Electronics
Group-NI ELVIS II Orientation Manual.
- Slide 160
- 160 Clemson ECE Laboratories
- Slide 161
- 161 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab VIII Pre-labs for ECE 211 Guneet Bedi Created: 11/09/2012
Updated: 11/09/2012
- Slide 162
- 162 Clemson ECE Laboratories
- Slide 163
- 163 Clemson ECE Laboratories Introduction A resistorcapacitor
circuit (RC circuit) or RC network, is an electric circuit composed
of resistors and capacitors driven by a voltage or current source.
A resistorinductor circuit (RL circuit) or RL network, is an
electric circuit composed of resistors and inductors driven by a
voltage or current source.
- Slide 164
- 164 Clemson ECE Laboratories Time Constant-RC Circuit The time
taken for the capacitor to charge or discharge to within a certain
percentage of its maximum supply value is known as its Time
Constant ( ). Mathematically, =RC
- Slide 165
- 165 Clemson ECE Laboratories Time Constant-RL Circuit The time
taken for the current in an inductor to grow or decay to within a
certain percentage of its maximum value is known as its Time
Constant ( ). Mathematically, =L/R
- Slide 166
- 166 Clemson ECE Laboratories Lab Objective By the end of this
lab, the student should know how to measure the time constants of
RC and RL circuits.
- Slide 167
- 167 Clemson ECE Laboratories Equipment Needed NI-ELVIS
workstation Resistance substitution box Capacitance substitution
box Inductance substitution box
- Slide 168
- 168 Clemson ECE Laboratories Procedure-RC Time Constant
Measurement (1) Set up the RC circuit shown in figure. Set the
function generator to give a square wave output with magnitude
equal to 500mV. Measure both the source voltage and the voltage
across the capacitor with the digital oscilloscope. Adjust the
frequency of the function generator so that the waveform shown has
definite flat sections at the top and bottom. Using the
oscilloscope cursors function, determine when the voltage reaches
0.632 times its final value.
- Slide 169
- 169 Clemson ECE Laboratories Procedure-RC Time Constant
Measurement (1) contd Sketch the waveform for a complete cycle in
your notebook, recording the voltage scale and time scale values.
Clearly label the sketched waveforms, including the initial and
final values. Repeat these steps using C=0.047F and C=0.1F. For
each circuit the frequency of the waveform generator may have to be
changed to achieve the flat sections at top and bottom of the
waveforms.
- Slide 170
- 170 Clemson ECE Laboratories Procedure-RC Time Constant
Measurement (2) Now modify the circuit as shown in figure. Repeat
the measurements in part 1 using C=0.01F, 0.047F, 0.1F while
observing the voltage across the resistor. Find the time when the
voltage reaches 0.368 times its initial value. Compare your
measured values of the RC circuit time constant in Parts 1 and 2
with the theoretical values.
- Slide 171
- 171 Clemson ECE Laboratories Procedure-RL Time Constant
Measurement (1) Set up the RL circuit shown in figure. Set the
function generator to give a square wave output with magnitude
equal to 500mV. Measure both the source voltage and the voltage
across the resistor with the digital oscilloscope. Adjust the
frequency of the function generator so that the waveform has
definite flat sections at the top and bottom. Using the
oscilloscope cursors function, determine when the voltage reaches
0.632 times its final value.
- Slide 172
- 172 Clemson ECE Laboratories Procedure-RL Time Constant
Measurement (1) contd Sketch the waveform for a complete cycle in
your notebook, recording the voltage scale and time scale values.
Clearly label the sketched waveforms, including the initial and
final values. Repeat these steps using L=400mH, 600mH and 800mH.
For each circuit the frequency of the waveform generator may have
to be changed to achieve the flat sections at top and bottom of the
waveforms.
- Slide 173
- 173 Clemson ECE Laboratories Procedure-RL Time Constant
Measurement (2) Now modify the circuit as shown in figure. Repeat
the measurements in part 1 using C=200mH, 400mH, 600mH and 800mH
while observing the voltage across the inductor. Find the time when
the voltage reaches 0.368 times its initial value. Compare your
measured values of the RC circuit time constant in Parts 1 and 2
with the theoretical values.
- Slide 174
- 174 Clemson ECE Laboratories Lab 8-Student Tasks Students are
required to solve the Probing Further section, given in the lab
manual, in their laboratory notebooks.
- Slide 175
- 175 Clemson ECE Laboratories Preparations for Next Week Review
the material in the textbook on the RLC circuit response. Review
the concepts of overdamped, underdamped, and critically damped
response. Calculate the theoretical parameter values of s 1, s 2, ,
d, and T for the circuit used in the lab (i.e., do Part 0 of the
Procedure).
- Slide 176
- 176 Clemson ECE Laboratories References ECE 211 Electrical
Engineering Lab I. Latest Revised July 2010. Wikipedia
- Slide 177
- 177 Clemson ECE Laboratories
- Slide 178
- 178 Clemson ECE Laboratories ECE 211 - Electrical Engineering
Lab IX Pre-labs for ECE 211 Guneet Bedi Created: 11/16/2012
Updated: 11/16/2012
- Slide 179
- 179 Clemson ECE Laboratories
- Slide 180
- 180 Clemson ECE Laboratories Introduction A series RLC circuit
(or LCR circuit) is an electrical circuit consisting of a resistor,
an inductor, and a capacitor, connected in series with the voltage
source. The RLC part of the name is due to those letters being the
usual electrical symbols for resistance, inductance and capacitance
respectively.
- Slide 181
- 181 Clemson ECE Laboratories Series RLC Circuit
Properties-Circuit Response The differential equation for the
circuit has the following characteristic equation or The circuit
response or the roots of the characteristic equation is given
by
- Slide 182
- 182 Clemson ECE Laboratories Series RLC Circuit Properties-, 0
& is called the neper frequency, or attenuation, and is a
measure of how fast the transient response of the circuit will die
away after the stimulus has been removed. Damping factor, is
defined as the ratio of and 0 0 is the angular resonance
frequency.
- Slide 183
- 183 Clemson ECE Laboratories Series RLC Circuit Properties-Time
Period (T) Let us define d as Where T=Time Period
- Slide 184
- 184 Clemson ECE Laboratories Transient Response-Overdamped
Response If is large compared with the resonant frequency o, the
voltage or current approaches its final value without oscillation,
and the non-oscillatory response is called overdamped. >1
- Slide 185
- 185 Clemson ECE Laboratories Transient Response-Underdamped
Response If is small compared to o, the response oscillates about
its final value, and this response is called underdamped. The
smaller the value of is, the longer the oscillation persists.