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ENGR4035 Basic Electrical Engineering
Module Guide Semester S1 2023- 24
School of Engineering, Computing and Mathematics
Faculty of Technology, Design and Environment
Module Leader: Dr. Amr Tammam
Office: R2.42
Contents
Contents
Module introduction
1
Module leader contact details<Mandatory>
1
Seminar leader contact details
1
Academic Liaison Librarian
1
Changes made to the module (if any) in response to student and other feedback 1
Module Study Plan
2
Module syllabus
3
Recommended reading list <Delete if it is available on Moodle site>
3
Assessment information <Mandatory>
3
Coursework <Mandatory if assessed via coursework>
3
Presenting coursework for assessment
3
Assignment length
4
Turnitin <Mandatory if applicable>
4
Submission date and instructions
4
Marking and moderation of your work
6
Feedback
6
Examination <Mandatory if assessed via examination>
7
Learning outcomes assessed
7
Format
7
Assessment criteria
7
Specimen examination paper<Remove if not applicable>
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Module introduction
Module leader contact details
Name:
Dr. Amr Tammam
Room:
R2.42, Wheatley Campus
email:
atammam@brookes.ac.uk
Office hours:
Wednesday 10.00am-12:00pm
Seminar leader contact details
Name:
Prof. Khaled Hayatleh
Room:
R221, Wheatley Campus
email:
khayatleh@brookes.ac.uk
Office hours:
Mondays 9-11, 11-12
Academic Liaison Librarian
Subject Librarian (Beth Paton)
Email: whlibenquiries@brookes.ac.uk
Website: https://www.brookes.ac.uk/profiles/staff/beth-paton
Website: https://www.brookes.ac.uk/library/resources-and-services/course-resource-help/engineering
Changes made to the module (if any) in response to student and other feedback.
This is a new module.
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Module Study Plan
Week starts
Lecture & Seminars
Mondays
Seminars/Simulations
Check your calendar for your set.
Please make sure you ask the lecturers for feedback
(Formative feedback). You are also encouraged to discuss
your work with your colleagues (Peer review)
1: 25th Sept
Uses and properties of electricity
2: 2nd Oct
Capacitors/Filters
3: 9th Oct
Inductors/Electro-Magnetic quantities
Seminar Week 1: Introduction to Multisim
No assessment- Formative feedback
Seminar Week 2: Basic circuits
No formal assessment-
Seminar Week 3: Rectifiers and transformers
No formal assessment- Formative feedback
th
4: 16 Oct
Transistors
5: 23rd Oct
Consolidation week
6: 30th Oct
Amplifiers
7: 6th Nov
Digital electronics
8: 13th Nov
RC circuits
9: 20th Nov
Analysis of AC circuits
10: 27th Nov
Electromagnetic circuits
11: 4th Dec
Battery Technology
Mini project- DC Power Supply Design
This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
Mini project- DC Power Supply Design
This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
Mini project-DC Power Supply Design
This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
Submit mini project report on DC Power Supply Design
(assignment) Monday week 7- 13:00 on 06/11/2023
Seminar Week 7: Op-amps
No formal assessment- Formative feedback
Seminar Week 8: Digital
No formal assessment- Formative feedback
Introduce Mini project- Delay Timer Design (Start
working at home)
Mini project- Delay Timer Design
This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
Mini project- Delay Timer Design
This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
Mini project- Delay Timer Design
This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
Submit mini project report on Delay Timer Design
(assignment) Monday week 12- 13:00 on 11/12/2023
12: 11th Dec
Summary of assessments:
1. Mini project report (assignment) on DC Power Supply Design, should be submitted to Turnitin by 13:00 week 7,
06/11/2023. Carries 50% of the total marks.
2. Mini project report (assignment) on DC Power Supply Design, should be submitted to Turnitin by 13:00 week 12,
11/12/2023. Carries 50% of the total marks.
● ALL reports must be uploaded via Moodle to Turnitin
The lecture and tutorial/seminar hours are indicative of the total contact time for the
module and Module Leader’s will adapt the use of lectures and seminars/tutorials to suit
the needs of the cohort and to address feedback from the cohort from mid semester
module evaluation.
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Module syllabus
MODULE AIMS
An introduction to electrical quantities and parameters and to the operation of electrical and
electronic components and circuits of relevance to Engineering students.
LEARNING OUTCOMES
On successful completion of this
module, students will be able to:
Brookes Attribute
developed*
Other GAs developed, if
applicable
1 Use mathematical skills to solve basic
problems in electrical and electronic
engineering.
Academic Literacy
Research Literacy
2 Understand and predict the general
operation and behaviour of electrical
and electronic circuits.
Academic Literacy
Research Literacy
3 Design basic electrical and electronic
engineering circuits.
Academic Literacy
Critical Self-awareness and
personal literacy
4 Perform research and literature reviews
for projects
Research Literacy
Academic Literacy
5 Demonstrating time management skills
in the execution of the mini projects;
Critical Self-awareness
and personal literacy
6 Produce designs for electrical and
electronic circuits giving due
consideration to issues of sustainability,
legislation and safety.
Active Citizenship
7 Evaluate and present results of miniprojects using different media including
presentations.
Digital Information Literacy
Academic Literacy
OUTLINE SYLLABUS
Give an indication of the topics to be covered during the course of the module (it may be
helpful to group by key topic areas, giving indicative examples of content covered under each
heading).
Developments of the use of Mathematics to analysis basic circuits.
Electrical quantities: current, voltage, charge, resistance, energy, power.
Kirchoff's laws, series and parallel resistor circuits, potential and current dividers,
measurement of voltage and current.
Principles of electromagnetics, operation of transformers and ac and dc generators and motors.
Simple L, C and R characteristics and applications.
Basic operation and applications of semiconductors.
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Use of operational amplifiers in designing simple circuits.
Use of digital circuits in designing simple circuits.
Self-management on assessments and mini project
Recommended reading list
Materials and resources will be made available on Brookes Virtual for the module during
the semester at appropriate points. Working on mini project Please ensure that you
check
Brookes
Virtual
regularly
at:
http://moodle.brookes.ac.uk/course/view.php?id=13040
You are encouraged to read independently around the subject and there will be a reading
list available on Brookes Virtual and also below:
Materials and resources will be made available on Brookes Virtual for the module during the
semester at appropriate points. Working on mini project Please ensure that you check Brookes
Virtual regularly at: http://moodle.brookes.ac.uk/course/view.php?id=13040
You are encouraged to read independently around the subject and there will be a reading list
available on Brookes Virtual and also some below:
●John Bird, Electrical Circuit Theory and Technology, ISBN 978-1138673496, 2017, Routledge.
●Giorgio Rizzoni, Principles and Applications of Electrical Engineering ISBN-- 13: 9780071072496,
2010, Tata McGraw-Hill Education Pvt. Ltd
●Thomas L Floyd, Electronics Fundamentals: Pearson New International Edition: Circuits, Devices
& Applications, Jul 2013, ISBN-13: 978-1292025681, Pearson
●Storey N, Electronics Circuits: A Systems Approach, Pearson ISBN-13: 978-0273773276; 2013
●Sergey N. Makarov, etl, “Practical Electrical engineering”, ISBN 978-3-319-21172-5, 2016,
Spinger.
●Spence R, Introductory Circuits, Wiley, 2008, 9780470779712
Assessment information
This module follows the principles of the University’s Assessment and feedback policy
developed in conjunction with the Student Union, to ensure good practice and
transparency in assessment and feedback processes. The Assessment and feedback
policy can be found in your Programme Handbook or on your Programme’s Brookes
Virtual site as well as on the University webpage of A-Z of Policies.
Please note: the Institutional University Handbook which will provide you with
information that is central to your studies, including policies and regulations, student
support and wellbeing and all the services available to you through Student Support.
The core information is also available on Moodle via the drop-down menu under
‘Student Help’.
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Coursework 1: Formal report for mini project on DC Power Supply Design (look at
Assignment for weeks 4, 5 and 6) - carries 50 % of the total marks)
You are required to write a formal report for the mini project- DC Power Supply Design.
Your Assignment Brief can be found in weeks 4, 5 and 6 of this module guide. Here
you will also find the assessment criteria outlining how marks will be awarded. You will
be taken through the coursework in a full briefing during your scheduled teaching hours.
Details of how you should present your work and when the work is due are detailed
below.
The maximum word count is 1500 and double line spaced. The final report should
be no more than 12 pages of A4. The diagrams should be clear enough for
someone to build your circuits.
●
●
●
●
●
●
Word count excludes, figure labels, tables, references, bibliography.
Appendices and abstract are not required.
Extra pages will not be marked.
The report must be uploaded via Moodle to Turnitin
Deadline: Week 7 (check Moodle page for date and time).
A comprehensive mark grid sheet is shown on Moodle page.
Coursework 2: Formal report for mini project on A Delay Timer (look at Assignment
for weeks 9, 10 and 11) - carries 50 % of the total marks)
You are required to write a formal report for the mini project-A Delay Timer. Your
Assignment Brief can be found in weeks 9, 10 and 11 of this module guide. Here you
will also find the assessment criteria outlining how marks will be awarded. You will be
taken through the coursework in a full briefing during your scheduled teaching hours.
Details of how you should present your work and when the work is due are detailed
below.
The maximum word count is 1500 and double line spaced. The final report should
be no more than 12 pages of A4. The diagrams should be clear enough for
someone to build your circuits.
●
●
●
●
●
●
Word count excludes, figure labels, tables, references, bibliography.
Appendices and abstract are not required.
Extra pages will not be marked.
The report must be uploaded via Moodle to Turnitin
Deadline: Week 12 (check Moodle page for date and time).
A comprehensive mark grid sheet is shown on Moodle page.
Presenting coursework for assessment
Your assignment must be presented in the following format:
❑
It must be word-processed in 12-point Arial font and double-spaced.
❑
All pages must be numbered.
❑
Margins must be as follows: Top: 1 inch, Bottom: 1 inch (2.5 cm), Left: 1.25 inches,
Right: 1.25 inches (3.2 cm)
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❑
It should not contain your name(s)
Turnitin
Coursework 1 and coursework 2 on this module will be submitted through Turnitin.
Turnitin is a web-based tool that supports the development of good academic practice
when preparing written work for assessment. This text-matching tool allows academic
staff to check assignments for improper use of sources or potential plagiarism by
comparing it against continuously up-dated databases (including web-pages and other
student work).
Submission date and instructions
Your work must be uploaded to the drop box in Moodle as follows:
1. Mini project report (assignment) on DC Power Supply Design, should be submitted to
Turnitin by 13:00 week 7, 06/11/2023. Carries 50% of the total marks.
2. Mini project report (Delay Timer) should be submitted to Turnitin by 13:00 week 12,
11/12/2023. Carries 50% of the total marks.
ALL reports must be uploaded via Moodle to Turnitin
Please ensure you submit your assignment no later than the deadline set above (these
are fixed deadlines, but students may exceptionally secure an extension if last minute
untoward circumstances affect your ability to submit on time).
Please note the use of this extension is monitored and restrictions in place for overuse.
You must make a request for any form of extension so please follow the link below to
identify how.
https://www.brookes.ac.uk/students/your-studies/exceptional-circumstances/
The Blue Marking Card adjustment is only available to students who have an Inclusive
Support Plan (ISP) specifying this adjustment. Eligible students who wish to use this
adjustment must add a blue card:
https://www.brookes.ac.uk/students/inclusive-support-service/exams-andassessments/blue-marking-cards
Recommendations for Reasonable Adjustments are made in accordance with the
provisions of the Equality Act 2010. These are detailed in Inclusive Support Plans
(ISPs) and need to be implemented unless there is a clear rationale for this not being
possible, in which case we are accountable as an HEI for this decision. Alternatives
should be considered, and further advice sought from the Inclusive Support Service to
ensure we are compliant, consistent, and following best practice.
Inclusive Support Plans (ISP) extensions (max 3 weeks) can be used. If you have an
Inclusive Support Plan you can check the full details of the adjustments, including
whether you have coursework extensions in Student Self Service
https://generalssbprod.ec.brookes.ac.uk/BannerExtensibility/customPage/page/student_ISP
It is not possible to give the full coursework extension period agreed in all Inclusive
Support Plans for assignment coursework one and/or coursework two, if your extension
will take your deadline past the University final deadline for submission of work you will
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not be able to use the full extension. Consideration must be given, when determining a
deadline for an extension period, to allowing enough time for submission of work and
marking, so that the module and marks can be taken to the correct examination
committee. If you have an Inclusive Support Plan you can check the full details of the
adjustments, including whether you have coursework extensions in
https://generalssbprod.ec.brookes.ac.uk/BannerExtensibility/customPage/page/student_ISP
If you have a coursework extension as part of an Inclusive Support Plan, contact your
module leader if you are unclear about your deadlines.
Students who have an extension because of an ISP or a successful exceptional
circumstances application (or both) can also use an extension if the need arises.
Contact the Inclusive Support Service if you would like to request a review of your
Inclusive Support Plan (ISP) or to have your needs assessed for an ISP.
Marking and moderation of your work
Following internal moderation, a sample of work is reviewed by the External Examiner
for the programme to ensure that the standards applied are comparable to those at
other institutions. To read how your work is moderated please go to your programme
handbook for details.
Feedback
Feedback on coursework one will be provided in a range of ways at various times
throughout this module, and different feedback will serve slightly different purposes.
Feedback is designed to support your learning and help you to improve subsequent
work, so you need to engage and get the most out of the feedback provided.
Please note that feedback is provided throughout the module not just on formal tasks It
will be provided on your work and contribution in class, on the formal assessment tasks
and, in some circumstances, during staff office hours.
If you would like further information about feedback, or how to use it, please talk to your
tutor on this module or your Academic Adviser or Programme Lead
Assessment feedback will normally be provided using a marking grid (rubric) and
notation via Moodle within 15 working days of submission.
Please note that all marks are provisional until they are ratified by an Examination
Committee.
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Seminars and Simulations
Assessment in this part of the module
READ THIS!
The formally assessed coursework comprises two mini projects
reports 50% each (total 100%). We call this summative assessment. The
deadlines and hand-in arrangements for this are given in the MOODLE
pages for the module.
As well as the formal summative assessment, there is a lot of formative
assessment in this booklet. All students are required to complete all the
seminars/simulations in this booklet and fill in all the required sections. This
booklet will be checked by the lecturers during the seminars. This is a
formative assessment – that means the only grades are “done” or “not
done”, and you get feedback.
There are two main themes for this series of seminars/simulations:
●
●
Applying knowledge gained from Lectures to analysis and solve fundamental
electrical and electronics circuits and systems problems.
Use Mulitism software to help you understand electrical and electronics circuits
and systems behaviour.
In these formative seminar sessions, you will be working in groups of 2
where you are expected to share and discuss the results of the simulations
with your colleague.
No formal assessment- Peer review and discussion. Peer reviewing is
VERY important, as you will do a lot of this when you get a job. Your own
work will also be reviewed by your peers (co-workers). Please take this
seriously, as it will enhance your knowledge and help with the assessment
in both mini-project and the class test at the end of the semester.
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Seminar Week 1
INTRODUCTION TO MULITISIM and basic electric circuits:
Note: This is a short introduction to Multisim. To be fully conversant with it, you need to explore
and experiment with it yourselves, in your own time. All this experience will be useful to you in
later taught modules and possibly your project module.
We want you to think carefully of the real-life implications and applications of the circuits you
work with. For instance, in the examples in the section, we will be using switches to operate
them. What could be used in place of switches? For instance, as input devices, perhaps you
could imagine them as sensors, such as light, sound, smoke, vibration etc. On the output side,
we use LEDs. Perhaps you could imagine them as motors, buzzers, solenoids etc.
Multisim is a computer simulation package that enables you to construct, test, & evaluate circuits.
To Open
Start the computer and in the main menu select Multisim, then under the file tab, select New.
Please note that you will be using multisim for all the exercise in this booklet.
Exercise. 1-1 – Measure voltage across resistor and current through resistor
Select Place then Component then resistor. You will see list of resistors.
You can right-click on the items to rename the component.
If you want to rotate it, try right-clicking on it.
Do the same with Place, Component, Sources, Power Sources, DC-POWER, 10V. This adds
the power lines. You get the mutlimeter from simulate, instrument then multimeter.
SAVE THE CIRUIT IN YOUR OWN FOLDER AS Exercise 1-1
1.1- Simulate the circuit of Fig.1-1. Confirm the voltage across resistor R1 and the current
through resistor R1 as shown in Fig.1-1.
Fig. 1-1. Basic resistor circuit
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In the circuit of Fig.1-1, vary V1 from 1V to 10V as shown in table 1-1, then measure the current
through R1 for different values of resistor R1 (R1 = 100 Ω, R1= 1kΩ, R1= 10kΩ, R1= 100kΩ.).
Complete table 1-1.
Table 1-1: Complete table 1-1
Voltage in
Volts
Current in mA
R1= 100Ω
Current in
mA
Current in mA
Current in mA
R1= 10kΩ
R1= 100kΩ
R1= 1kΩ
1.0
2.0
3:0
4:0
5:0
6:0
7:0
8:0
9:0
10.0
Use EXCEL, plot a graph voltage (Y axis) against current (X axis), Comment briefly on the
results, saying why you think the resistance changes in the way that it does.
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Exercise 1-2 – Two resistors in series
Simulate the circuit of Fig.1-2. Confirm the voltage across resistor R1 and the current through
resistor R2 as shown in Fig.1-2.
Fig.1-2 – Two resistors in series
In the circuit of Fig.1-2, vary V1 from 1V to 10V as shown in table 1-2, then measure the current
through R2 for different values of resistor (for R1 = 1kΩ, R1= 2kΩ, R1= 3kΩ, R1= 4kΩ) as shown
in table 1-2.
Table 1-2: Complete table 1-2
Voltage in Volts
Current in mA
R1= 1kΩ
Current in mA
Current in mA
Current in mA
R1= 2kΩ
R1= 3kΩ
R1= 4kΩ
1.0
2.0
3:0
4:0
5:0
6:0
7:0
8:0
9:0
10.0
Use EXCEL, plot a graph voltage (Y axis) against current (X axis), Comment briefly on the
results.
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Exercise. 1-3A Conventional bulb (Fig.1-3A)
In this first experiment we will vary the current through a conventional bulb and see how the
resistance changes as the brightness increases.
Fig.1-3A Conventional bulb
Connect up the circuit as in the diagram of Fig.1-3A. Then measure the current at voltages of
2.0, 4.0, 6.0 and etc. up to 16 Volts. Complete the table below. The resistance in calculated using
the formula: 𝑅=
𝑉
𝑉𝑜𝑙𝑡𝑎𝑔𝑒
=
𝐼
𝐶𝑢𝑟𝑟𝑒𝑛𝑡
However, there is a complication! The current is in milleAmps. So, watch out for that. (Simplest
to divide the current by 1000, so 25mA becomes 0.025 Amps.). Complete table 1-3A.
Table 1-3A: voltage, current and resistance
Voltage in Volts
Current in mA
Resistance in Ohms
measured
calculated
2.0
4.0
6:0
8:0
10:0
12:0
14:0
16:0
Use EXCEL for table 1-3A, plot a graph of current (Y axis) against voltage (X axis). Comment
briefly on the results, saying why you think the resistance changes in the way that it does.
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Exercise. 1-3B
Conventional bulb with fuse (circuit Fig. 1-3B)
Fig.1-3B Conventional bulb with fuse
(i) Simulate the circuit of Fig.1.3B, conventional bulb with fuse. Does the circuit work- explain
why?
(ii) Work out the most suitable value for the fuse, so that the circuit works. Simulate your
suggested value and confirm performance?
(iii) Redesign the values of the circuit of Fig.1-3B Conventional bulb with fuse using V1=5 V, and
the lamp is 5V, 1W. workout a suitable value of the fuse so that the circuit works. Simulate your
suggested value and confirm performance?
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Exercise 1-4: - Oscilloscope and AC signals
A multimeter is very useful for measuring voltage, current or resistance when they are constant.
If a voltage is constantly changing, especially when changing quickly, the voltmeter is not much
use.
If the voltage is changing, we use an oscilloscope.
Many sensors give out voltages that continually changing, and lots of other circuits too.
For this part of the experiment, we use the AC voltage source. This generates voltages that
continually change in all sorts of way. Set it up to generate a Sine wave of frequency 1Hz and
peak voltage of 5V, as shown in Fig 2-2.
Fig. 1-4 - AC signal with Oscilloscope
Simulate the circuit of Fig. 1-4. Explain your results? Is this what you expected?
Please make sure you finish on your own time Seminar Week 1 before next week.
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Seminar Week 2
Exercise. 2-1
Light Emitting Diodes
In this experiment we use a different light source, which behaves COMPLETELY differently. A
Light Emitting Diode (LED) also changes electrical energy into light, but the way the current
change with voltage is totally different. It does not obey Ohm’s Law at all.
An LED is easily broken (in real life application) by having too much current pass through it, so
we use a resistor to keep the current low. In this experiment, we use one resistor, 470 ohms.
Unlike the bulb, the LED must be connected the correct way round. See the picture under
the diagram.
The LED looks like this: -
The longer lead
is connected to
+, through the
resistor in this
case.
The circuit of Fig.2-1 is a basic LED circuit.
The shorter
lead is
connected to
minus.
Fig. 2-1 LED circuit
Simulate the circuit of Fig. 2-1. start with the RED LED. Set the supply to 5 Volts. Gradually
increase the voltage and check that the LED comes on. If not, sort out the circuit!
Now, the point of the experiment is to see how the voltage across the LED changes when the
current increases. The result will be completely different to the bulb. Use the ammeter in the
supply to read the current. Adjust the power supply voltage till the current is 5 mA. Read the
voltage across the LED using a multimeter – do not read the power supply voltage, which is
not of any interest!
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Then increase the voltage till the current is 10 mA. Record the LED voltage again. Keep doing
this in 5mA steps up to 25 mA. Repeats this experiment for Red LED, Green Led and Yellow
LED. Record the results in a table. 2.1
Table 2-1 Voltages for different LEDs
Red LED
LED current in mA
voltage in Volts
0.0
Green LED
Yellow LED
voltage in Volts
voltage in Volts
0.0
5
10
15
20
25
Use EXCEL, Plot of graph for table 2-1 of current (Y axis) vs voltage (x axis) for Red, green
and Yellow LEDs on ONE graph, and stick the graph in this booklet on the next page.
Remember the zero Volts giving zero current point should be on the graph. Comment briefly on
the results, comparing them with the results from the bulb.
Exercise 2-2:
Diodes
This experiment has three parts. The first is to do with rectification, changing AC to DC. The
second deals with LEDs and Zener diodes. The third looks at how Zener diodes can keep
voltages within safe limits.
Objectives
The objectives of this experiment are: ● To confirm in simulation points about diodes covered in lectures, particularly how
rectifier diodes and Zener diodes behave.
● To practice simulating circuits
Normal diodes
Zener diodes
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Rectification
Rectification is the changing of alternating current (AC), as made by the alternator in a car, into
the direct current (DC) as needed by the car’s electrical equipment. Mains electricity is also AC
and must be changed to DC for use in electronics equipment like computers and music systems.
We use the AC signals to make the Alternating Current source (from an AC voltage source) as
shown in Fig. 2-2A. This time the frequency is 1KHz with 10V peak signal.
Fig. 2-2A Basic half wave rectifier circuit
Now test the effect of a smoothing capacitor. Capacitors store a small amount of electrical
energy and can “hold up” the voltage during the time when the rectified AC wave falls away as
shown in the circuit of Fig.2-2B.
Fig. 2-2B Basic half wave rectifier circuit with a capacitor
Simulate the circuit of Fig. 2-2B. Explain your simulation results?
Repeat the simulation of the circuit of Fig. 2-2B by choosing five different capacitor values such:
(a) 6.8μF
(b) 33μF
(c) 330μF
(d) 680μF
(e) 6800μF
Explain your results. What do you conclude?
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Exercise 2.3:
Zener diode voltage stabilisation
A big problem in cars is that the voltage can rise well above 12 Volts on occasions. This is due
to the battery charging, and even larger variations come from voltage “spikes” getting in from the
ignition system. If we do not take care, these high voltages can easily damage electronic
equipment like radios, engine management units, ABS controllers and the like. Zener diodes are
used to make sure the voltage stays safe. This experiment will show you how this works.
Simulate the circuit as in Fig. 2-3. The power supply is connected to a 330 Ω resistor, but there
is a “backwards” connected Zener diode as well. A voltmeter measures the voltage coming out
of this little circuit.
Fig. 2-3 Zener diode voltage stabilisation
However, now increase the supply voltage by 2.0 Volts, up to 18 Volts. (4,6,8, 10,...18 Volts) Put
the simulation results table.2.3.
Table 2.3 complete this table.
Voltage after Zener Diode
Voltage from supply (V)
You measure (V)
4.0
4.0
6.0
8.0
10.0
12.0
14.0
16.0
18.0
Use EXCEL, Plot a graph, with the supply voltage on the x (across) axis, and the voltage after
the Zener diode on the y (up) axis, and stick the graph in here.
Please make sure you finish on your own time Seminar Week 2 before next week.
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Seminar Week 3
Rectifier and Filter: Analysis of a full bridge rectifier and filter
A full-wave bridge rectifier is a single-phase rectifier, which uses four individual rectifying diodes
connected in a closed-loop “bridge” configuration to produce the desired output.
Fig 3.1 shows four diodes labelled D1 to D4 that are arranged in “series pairs” with only two
diodes conducting current during each half cycle. During the positive half cycle of the supply,
diodes D1 and D2 conduct in series while diodes D3 and D4 are reverse biased and the current
flows through the load as shown below.
During the negative half cycle of the supply, diodes D3 and D4 conduct in series, but diodes D1
and D2 switch “OFF” as they are now reverse biased. The current flowing through the load is the
same direction as before.
Fig. 3.1. Full bridge rectifier
As the current flowing through the load is unidirectional, so the voltage developed across the
load is also unidirectional the same as for the previous two-diode full-wave rectifier. Therefore,
the average DC voltage across the load is 0.637Vmax.
However, in reality, during each half-cycle, the current flows through two diodes instead of just
one, so the amplitude of the output voltage is two voltage drops ( 2*0.7 = 1.4V ) less than the
input VMAX amplitude. The ripple frequency is now twice the supply frequency (e.g., 100Hz for
a 50Hz supply or 120Hz for a 60Hz supply.)
Fig. 3.2. Full bridge rectifier. Current through diodes D4 and D3
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The smoothing capacitor converts the full wave rippled output of the rectifier into a smooth DC
output voltage. If we now run the simulator with different values of smoothing capacitor installed,
we can see the effect it has on the rectified output waveform as shown in Fig. 3.3.
Fig. 3.3. Full bridge rectifier. DC output filter
The capacitor can be calculated approximately from the equation:
𝐶 = 0.7
𝐼
∆𝑉 × 𝐹
Where, I is the current through the load; ∆𝑉 is the accepted voltage ripple; F is the frequency
after rectification.
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Calculate the necessary capacitor for the next tasks:
1.
2.
3.
4.
∆𝑉
∆𝑉
∆𝑉
∆𝑉
= 1 𝑉; I = 1A; F = 100 Hz.
= 500 𝑚𝑉; I = 0.5A; F = 100 Hz.
= 500 𝑚𝑉; I = 2A; F = 50 kHz.
= 100 𝑚𝑉; I = 3A; F = 100 kHz.
For example, if ∆𝑉 = 300 𝑚𝑉; I = 0.3A; F = 100 Hz, then:
𝐶 = 0.7 ×
0.3
= 0.007𝐹 𝑜𝑟 7000 𝜇𝐹
0.3 × 100
Modelling with Multisim.
Study and simulate the circuit of Fig 3.4. (Notes S1 is switch.)
Fig. 3.4. Rectifier Multisim simulation
Study the level of output ripple by switching the number of capacitors in parallel with the
switch (S1).
For example, all switches are OFF (see Fig 3.5):
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Fig. 3.5. Rectifier Multisim simulation
In Fig. 3.6 only 4.7 µF capacitor is ON.
Fig. 3.6. Rectifier Multisim simulation
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Transformer: Analysis of low-frequency transformer.
A transformer is a magnetically coupled circuit, i.e., a circuit in which the magnetic field produced
by the time-varying current in one circuit induces a voltage in another. It consists of two coils
wound on a common core. Alternating current in one winding establishes a flux which links the
other winding and induces a voltage in it. Power thus flows from one circuit to the other via the
medium of the magnetic field, with no electrical connection between the two sides.
The winding to which we supply power is called the primary, while the winding from which we
take power is called the secondary. Power can flow in either direction, as either winding can be
used as the primary or the secondary see Fig. 3.7A.
Fig. 3.7A. Construction of a low-frequency transformer.
Transformer equations:
Fig. 3.7B. transformer equations.
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Modelling with Multisim
A model of a transformer and the necessary experimental circuit is shown below in Fig. 3.7C.
Simulate this circuit and adjust the transformer turns ratio and observe the output voltage
and current using the multimeters and oscilocope. You should get similar results to Fig. 3.7D.
We encourage you to investigate the circuit and discuss with your colleagues. For example try
different ratios of transformer to observe stepping up or stepping down the voltage and current.
Figure 3.7C Transformer circuit
Fig. 3.7D Transformer circuit with waveforms and results.
Please make sure you finish Seminar Week 3 on your own time Before next week.
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Assignment for weeks 4, 5 and 6
DC Power Supply Design (Mini Project)
NOTE: This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
You are allowed to discuss your work with colleagues (peer review),
just as you would if you had a job as an engineer. However, TAKE
CARE NOT TO COLLUDE, as your work will be checked (via Turnitin
and staff scrutiny) for similarities to other submitted work.
This mini project is split into four sections. The first section (part A) requires you to investigate
an existing circuit and then calculate the correct values for the components to make the circuit
perform to specifications. Part A also involves the simulation and measurement of its operating
parameters. You will then have to explain its operation, mentioning the purpose of every
component in the circuit. The second section (parts B) requires you to redesign the circuit to
enhance its operation according to the new design parameters. In each instance, you will have
to simulate the circuit, make sure it performs to specifications, and finally discuss the limitations
of your design, along with any improvements that could be made. When implementing the
circuit(s), consider the PRACTICAL considerations, and mention these in your report. The third
section (parts C) requires you to modify your design of Part A (Q4). The fourth section (parts D)
requires you to redesign the original system shown in Fig 4.1, so that the LED comes on for 5
minutes after it gets dark outside (that is, as evening falls - dusk)
Now that you understand what is required, you can progress to the mini project itself. In this mini
project, a stabilised DC power supply for an electronic circuit is derived from the AC mains using
the power supply shown in (Fig. 4.1). The value of the capacitor in the circuit can be assumed to
be very large, greater than 100𝜇𝐹. You should do the mini project work in pairs, but your reports
must be individual and your own.
Aim:
Investigate, design, simulate and analyse a DC power supply.
Objectives:
●
Design all the values for the circuit of Fig. 4.1 and answer questions Q1 to Q3 fully. Confirm that
the specifications are met and note any particular difficulties you encountered or any original
methods you used.
● Redesign the circuit of Fig. 4.1 to give an output current of 2.5𝐴. This should be done by changing
some components and the circuitry following the transformer. Explain your proposed system.
Simulate and explain the performance and limitations of the system. How could you improve on
the limitations?
●
Discuss the practical limitations of the circuit of Fig. 4.1 and suggest way that the circuit
might be improved to give better performance.
●
Write up your design and results of testing in a convincing report.
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Fig 4.1 - Stabilised Power Supply
You may choose one of the following bipolar transistors:
2N3055G
ZTX869
ZTX851
ZTX849
Part A (30%)
Q1. Design all the values for the circuit of Fig. 4.1 so that the output voltage at the load is 12𝑉
DC and the output current is 25𝑚𝐴. Assume that each diode's forward, or 'ON' voltage is 0.7𝑉.
Q2. Simulate the circuit of Fig. 4.1 using your designed values of Q1. Show all the output voltages
and currents in the circuit. Compare and discuss your calculated values with the simulation
results.
Q3. Calculate the values for I1, IL, IZ and VL for each of the following load resistor values:
𝑅𝐿 = 10𝑘Ω, 1𝑘Ω, 100Ω, 50Ω, 30Ω
Compare and discuss your calculated values with the simulation results.
Discuss the practical limitations of the original circuit of Fig. 4.1 and suggest way that the circuit
could be modified to give better performance.
Part B (15%)
Q4. Redesign the output of the circuit in Fig. 4.1 to give an output current of 5𝐴, which would be
required for charging a typical NiCad battery (300 Milli-Ohms). Explain your proposed system.
Simulate and explain the performance and limitations of the system. How could you improve on
the limitations?
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Part C (15%)
Q5. Modify your design of Part A so that the output voltage can be varied between 12V and 0V
using a potentiometer and for 𝑅𝐿 = 10𝑘Ω. Use only discrete components and not a chip.
Explain your proposed system. Simulate and explain the performance and limitations of the
system. How could you improve on the limitations?
Part D (20%)
Q6.
Using only transistors as the active components (no integrated circuits or logic gates etc),
design a circuit to flash 2 LED’s at a frequency of 1Hz. The 2 LED’s should flash in
antiphase, that is, one is on when the other is off – in effect, they flash alternately.
Simulate your circuit, explain the operation of ALL the components used. Explain the
outcomes of your simulation, along with a discussion of any limitations and how these
could be improved upon.
THIS IS TO BE INDIVIDUALLY DONE YOUR OWN TIME AND NOT DURING THE
OFFICIAL LAB SESSIONS. YOU ALSO NEED TO DEMONSTRATE YOUR OWN
ORIGINAL CONTRIBUTION – THAT IS, BY DESIGNING THE CIRCUIT YOURSELF
AND NOT RELYING ON CIRCUITS THAT YOU HAVE FOUND ON THE INTERNET.
ANY CIRCUITS THAT YOU USE MUST BE JUSTIFIED, EXPLAINED, AND MODIFIED
TO SUIT THE ASSIGNMENT REQUIREMENTS.
IMPORTANT NOTE: 20% of the marks for this mini project are for the introduction,
conclusion, presentation and references.
Therefore, you must be careful to bear this in mind when writing your report. You cannot expect
good marks if you do not introduce your work properly, as it just wouldn’t make any sense.
Likewise with the conclusion. If you do not say what you found, then it’s really all been a waste
of time. To back up your arguments and points you should use high quality evidence (references)
- and not just websites.
Finally, your work should be presented professionally – just like textbooks and journals are. For
instance, you need to CLEARLY LABEL EACH SECTION to show the reader EXACTLY which
question you are answering, and EXACTLY which part of the question you are answering.
Guidelines for writing up lab/Mini project
●
●
●
●
●
●
●
The individual report must be word-processed using Arial Font, size 12pt and double line
spaced. The maximum word count is 1500. The final report should be no more than 12 pages
of A4. Support all your points with high-quality academic references - not just websites.
Word count excludes, figure labels, tables, references, bibliography.
Appendices and abstract are not required.
Extra pages will not be marked.
Please refer to the Marking Grid mini project on Moodle as it has comprehensive information. A
summary of the distribution of marks is shown below.
Also, please refer to page 7 of the module guide regarding "Presenting coursework for
assessment.
THIS IS TO BE INVIDUALLY DONE IN YOUR OWN TIME, AND YOU NEED TO
DEMONSTRATE YOUR OWN ORIGINAL CONTRIBUTION – THAT IS, BY
DESIGNING THE CIRCUIT YOURSELF AND NOT RELYING ON INTERNET
SEARCHES. WE WILL BE CHECKING FOR THIS.
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NOTE: This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
You are allowed to discuss your work with colleagues (peer review),
just as you would if you had a job as an engineer. However, TAKE
CARE NOT TO COLLUDE.
Your work will be checked (via Turnitin and staff scrutiny) for
similarities to other submitted work.
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Seminar Week 7
Op-amp circuits:
7.1: simulating the following inverting negative feedback circuit shown in Fig. 7.1:
Fig. 7.1. Inverting negative feedback circuit
Select Place then Component (from anlog, Op Amp) the 741. Then select resistors,
power supply and ground.
Select Place then Component (from sources, signal _voltage_sources) the
AC_Voltage.
Select simulate, Instrument, Oscilloscope.
Confirm your simulation results with theory.
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7.2:
Design and simulate the non-inverting negative feedback circuit shown in Fig 7.2 so that
the voltage gain is 15. Confirm your simulation results with theory.
The power supply to the op-amp is +/- 12V.
Fig. 7.2 non-inverting negative feedback circuit
7.3:
Design and simulate the two-stage op-amp circuit shown in Fig 7.3 so that the overall gain
is 50. Confirm your simulation results with theory.
The power supply to the op-amp is +/- 12V.
Fig. 7.3 Two-stage op-amp circuit shown.
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7.4:
Design and simulate the differential amplifier circuit shown in Fig 7.4 so that the overall
gain is 9. Confirm your simulation results with theory.
The power supply to the op-amp is +/- 12V.
Fig. 7.4. differential amplifier circuit
Please make sure you finish Seminar Week 7 on your own time Before next week.
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Seminar Week 8
Seminar 8-1: Simulate the circuit of Fig. 8-1.
Select Place then Component the TTL. You will see Logic Gates. Click on 7408N, which is an
AND gate. Drag it onto the drawing area. This adds U1 in the diagram below.
Next, select Place then Basic then Switch. You will (of course) see a list of different switch
types. Select SPDT. This will add switch SW1 in the diagram. You can either repeat the process
to add SW2, or you can copy and paste SW1. You can right-click on the items to rename them.
Do the same with….
Place, Component, Sources, Power Sources, Vcc, 5V. This adds the power lines.
Place, Component, Sources, Ground. This adds the ground line.
Place, Component, Diode, LED. This adds the LED.
Place, Component, Basic, Resistor, 150Ω. This adds R1. If you want to rotate it, try
right-clicking on it.
Now, by dragging the components around, place them approximately in the same places as in
the diagram below.
Now, by clicking on the connections and dragging, you should be able to join the components
together as per the diagram.
Fig. 8-1 And circuit
SAVE THE CIRUIT IN YOUR OWN FOLDER.
Now, by pressing the green ‘Run’ button (it looks like a Play button), you will start the
circuit simulation.
Try all combinations of opening and closing the two switches. In what combinations does
it light. What uses could such a circuit be put too?
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Seminar 8-2: Simulate the circuit of Fig. 8-2.
Replace U1, the 7408N, with a 7400N as shown below.
Fig. 8-2 Nand circuit
SAVE THE CIRUIT IN YOUR OWN FOLDER.
Again, try all combinations of opening and closing the two switches.
combinations does it light. What uses could such a circuit be put too?
Seminar 8-3: Simulate the circuit of Fig. 8-3.
Now, use a 7486N for U1 as shown below.
Fig. 8-3 EXOR circuit
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SAVE THE CIRUIT IN YOUR OWN FOLDER.
Again, try all combinations of opening and closing the two switches.
combinations does it light. What uses could such a circuit be put too?
In what
Seminar 8-4: Simulate the circuit of Fig. 8-4.
Finally, build the circuit shown below.
Fig. 8-4 Nor with Inverter circuit
SAVE THE CIRUIT IN YOUR OWN FOLDER.
Again, try all combinations of opening and closing the two switches.
combinations does it light. What uses could such a circuit be put too?
Seminar 8-5:
Draw a logic circuit using AND and OR gates for the Boolean expression:
Y = (A + B) . (A + B)
Write out the truth table and state what single gate it is equivalent to.
Prove this using Mutilsim.
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Seminar 8-6:
Find the expression for the network shown below (Fig. 8-5). Implement this circuit in
Multisim and confirm the truth table for your design is correct.
Fig.8-5 combinational logic circuit
Please make sure you finish Seminar Week 8 on your own time Before next week.
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Assignment for weeks 9, 10 and 11
Mini project
-
A Delay Timer
ASSESSED: 50% of total module marks
NOTE: This is an INDIVIDUAL assessed report, so your work MUST be
your own. However, you are allowed to discuss your work with
colleagues (peer review), just as you would if you had a job as an
engineer. Do take care not to COLLUDE though, as your work will be
checked (via Turnitin and staff scrutiny) for similarities to other
submitted work.
This mini project is split into 2 sections. The first section (part A) requires you to investigate an
existing circuit. This involves simulation and measurement of its operating parameters. You will
then have to explain its operation. The second section (parts B to D) requires you to redesign
the circuit to enhance its operation according to design parameters that you are given. In each
instance you will have to simulate the circuit, make sure it performs to specifications, and finally
discuss the limitations of your design, along with any improvements that could be made. Always
bear in mind the PRACTICAL considerations when implementing the circuit(s).
Now you understand what is required, you can progress to the mini project itself. In this mini
project a potentiometer is used to control the time that an LED is turned on for. The unit could
be used to form the basis of a photographic exposure meter timer, a car ceiling lights or any
other similar application. You should do the mini project work in groups of two, but your reports
must be individual and your own.
Aim:
Investigate, re-design, simulate, and analyse a delay timer system.
Objectives:
●
●
●
●
Answer questions Q1 to Q4 fully. Confirm that the specifications are met and note any
particular difficulties you encountered, or any original methods that you used.
Redesign the delay timer system of Fig 9.1 using discrete components and NOT
integrated circuits, such as a comparator chip.
Redesign the delay timer of Fig 9.1 using only digital logic gates as the active
components. The LED should flash for a set period. Simulate your proposed system
and explain performance and limitations.
Redesign the original circuit of Fig 9.1 so the LED comes on for 5 minutes after the
room becomes dark.
Part A: (30%)
Simulate the system shown in Fig 9.1 using Multisim. Initially set the Variable voltage source
VB=1.5V, and ‘open’ the switch and leave it ‘open’. Note an ‘open switch’ is not conducting and
a ‘closed switch’ is conducting.
When you open the switch, the LED should remain ON, then after a short interval go off. Repeat
this sequence by momentarily closing the switch then opening it again. Note that almost instantly
the switch is closed the LED comes ON.
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Q1.
Monitor and record the voltages at pins 2 and 3 of U1, keeping an eye on the LED
status. At what voltage on pin 2 does the LED go out? Can you explain why it is no
longer ON? Check and record the voltage changes at pin 6 of 741 op-amp (U1) when
the LED is ON and OFF.
Q2.
Now try changing VB for different set voltages (take a step of 0.2V) between say
VB=1V to VB=3V and obtain the ON time (T-ON) (horizontal) on ordinary (linear– linear)
graph. Do you recognise the shape of the curve? If so, what it is?
Now, set VB=7V. What happens to the LED and why? Explain what U1 (741 op-amp)
is doing?
Q3.
The next step is to investigate the current flowing in the transistor (bipolar junction
transistor or BJT) Q3. Set the switch to keep the LED OFF and note the values of
voltages on Q3 terminals (collector, base and emitter). Now get the LED ON and
keep it ON. Measure and record, the voltages across R2 and R4 and calculate the
values of IB and IC, these being the base and collector currents respectively. Can
you deduce from these measurements the function of Transistor Q3 in the system?
Q4.
Go back to the operating conditions needed to get the timer to work for a relatively
short time interval and generally probe and record voltages throughout the circuit to
see exactly what is happening and try to come up with a brief explanation of how the
timer operates.
Explain the operation of the Delay Timer System of Fig. 9.1. Discuss the and explain the
performance and limitations of the system. Suggest how could you improve on the limitations?
Part B: (15%)
Q5.
Redesign the delay timer system of Fig 9.1 using only discrete components (E.g.
transistors, capacitors and resistors etc, NOT integrated circuits), so your circuit
should NOT include a comparator chip. Explain your proposed system. Simulate and
explain the performance and limitations of the system. How could you improve on the
limitations?
Part C: (15 %)
Q6.
Redesign the system of Fig 9.1 using only digital logic gates for the active components
such as AND and OR etc (NOT a 555-timer chip), to flash the LED at 2Hz for a period
of 5 seconds. Simulate and explain the performance and limitations of the system.
How could you improve on the limitations?
Part d: (20 %)
Q7.
Redesign the original system shown in Fig 9.1, so that it can operate a mains table lamp.
Simulate and explain the performance and limitations of the system. Discuss the practical
integration, implementation and limitations of your system. How could you improve on the
limitations?
THIS IS TO BE INVIDUALLY DONE IN YOUR OWN TIME, AND YOU NEED TO
DEMONSTRATE YOUR OWN ORIGINAL CONTRIBUTION – THAT IS, BY
DESIGNING THE CIRCUIT YOURSELF AND NOT RELYING ON INTERNET
SEARCHES. WE WILL BE CHECKING FOR THIS.
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NOTE:
20% of the marks for this mini project are for the introduction, conclusion,
presentation and references, so be careful to bear this in mind when writing your report.
You cannot expect good marks if you don’t introduce your work properly, as it just
wouldn’t make any sense. Likewise with the conclusion. If you don’t say what you found,
then it’s really all been a waste of time. To back up your arguments and points you should
use high quality evidence (references) - and not just websites. Finally, your work should
be presented professionally – just like textbooks and journals are.
Fig 9.1 - A Delay Timer System
IMPORTANT NOTE: 20% of the marks for this mini project are for the introduction,
conclusion, presentation and references.
Therefore you must be careful to bear this in mind when writing your report. You cannot expect
good marks if you don’t introduce your work properly, as it just wouldn’t make any sense.
Likewise with the conclusion. If you don’t say what you found, then it’s really all been a waste of
time. To back up your arguments and points you should use high quality evidence (references)
- and not just websites.
Finally, your work should be presented professionally – just like textbooks and journals are. For
instance, you need to CLEARLY LABEL EACH SECTION to show the reader EXACTLY which
question you are answering, and EXACTLY which part of the question you are answering.
Guidelines for writing up lab/Mini project
●
●
The individual report must be word-processed using Arial Font, size 12pt and double line
spaced. The maximum word count is 1500. The final report should be no more than 12 pages
of A4. Support all your points with high-quality academic references - not just websites.
Word count excludes, figure labels, tables, references, bibliography.
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●
●
●
●
Appendices and abstract are not required.
Extra pages will not be marked.
Please refer to the Marking Grid mini project on Moodle as it has comprehensive information. A
summary of the distribution of marks is shown below.
Also, please refer to page 7 of the module guide regarding "Presenting coursework for
assessment.
NOTE: This is an INDIVIDUALLY assessed report, so the work you
submit MUST BE YOUR OWN.
41