Cambridge
TECHNICALS
CAMBRIDGE TECHNICALS
IN ENGINEERING
LEVEL 3 UNIT 4 – PRINCIPLES OF ELECTRICAL
AND ELECTRONIC ENGINEERING
RESOURCES LINK
December 2014
Introduction
Resources Link is an e-resource, provided by OCR, for teachers of OCR
qualifications. It provides descriptions of, and links to, a variety of independent
teaching and learning resources that you may find helpful.
In Resources Link you will find details of independent resources, many of which are free:
where this is the case this has been indicated.
If you know of other resources you would like to see included here, or discover
broken links, please let us know. We would also like to hear from you if have any
feedback about your use of these, or other, OCR resources. Please contact us at
resourcesfeedback@ocr.org.uk.
We leave it to you, as a professional educator, to decide if any of these resources are
right for you and your learners, and how best to use them.
2
Cambridge
TECHNICALS
Resources Link
Contents
Fundamentals of Electrical Engineering and Electronics
4
Voltage regulators
23
Electrical Units
5
Power supplies and load regulation
24
Safe meter usage
6
Fuses and circuit breakers
25
Resistor Combinations
7
Diodes26
Kirchhoff’s Laws
8
Analog(ue) vs Digital
27
What is alternating current (AC)?
9
Op Amps
28
The AC Waveform
10
Op Amps – inverting and non-inverting
29
Phase Difference and Phase Shift
11
The summing op-amp
30
AC circuits: alternating current electricity
12
Online circuit simulator
31
Resistors, capacitors and inductors in AC circuits
13
Online op-amp simulator (from Texas Instruments)
32
Electric motors and generators
14
Introduction to digital logic gates
33
Types of DC Motor
15
Logic gate truth tables
34
Types of DC generator
16
Converting truth tables to Boolean expressions
35
Starting of DC motor
17
Online logic simulator
36
Speed control methods of DC motors
18
Basic flip flops
37
Single-phase power systems
19
The D-Type flip flop
38
Three-phase power systems
20
JK and T type flip flops
39
Three-phase electrical power
21
Online simulation software
40
Rectifier circuits
22
Data sheets online
41
3
Cambridge
TECHNICALS
Resources Link
Fundamentals of Electrical Engineering and Electronics,
2007, T.R. Kuphaldt and various co-authors
Description:
Free online book covering a full range of electrical
and electronic theory and practice.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Online book
http://www.vias.org/feee/index.html
4
Cambridge
TECHNICALS
Resources Link
Electrical Units
Description:
A basic introduction to electrical units. Includes
links to further tutorials on electrical formulae.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.engineeringtoolbox.com/electrical-units-d_454.html
5
Cambridge
TECHNICALS
Resources Link
Safe meter usage
Description:
A good introduction on how to make electrical
measurements, including voltage, current resistance
using a multimeter.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_1/chpt_3/9.html
6
Cambridge
TECHNICALS
Resources Link
Resistor Combinations
Description:
Excellent introduction to resistor circuits including
resistors in series and parallel.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.physicsclassroom.com/class/circuits/Lesson-4/
Combination-Circuits
7
Cambridge
TECHNICALS
Resources Link
Kirchhoff’s Laws
Description:
A good introduction to Kirchhoff’s first and second
laws.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/dccircuits/dcp_4.html
8
Cambridge
TECHNICALS
Resources Link
What is alternating current (AC)?
Description:
Introduction to AC theory – includes generation
and transmission and links to further detailed
worksheets.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_2/chpt_1/1.html
9
Cambridge
TECHNICALS
Resources Link
The AC Waveform
Description:
An introduction to the theory of the AC waveform –
including amplitude, frequency and periodic time.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/accircuits/ac-waveform.html
10
Cambridge
TECHNICALS
Resources Link
Phase Difference and Phase Shift
Description:
An introduction to the concept of phase and phase
angle in AC circuits.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/accircuits/phase-difference.html
11
Cambridge
TECHNICALS
Resources Link
AC circuits: alternating current electricity
Description:
An introduction to AC theory including the
behaviour of inductors and capacitors in AC circuits.
Has some useful animated graphics illustrating
phase difference.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.animations.physics.unsw.edu.au//jw/AC.html
12
Cambridge
TECHNICALS
Resources Link
Resistors, capacitors and inductors in AC circuits
Description:
An introduction to the behaviour of resistors,
inductors and capacitors in AC circuits, including
phasor diagrams. 12 page PDF including diagrams.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Online PDF
http://www.physics.ryerson.ca/sites/default/files/u11/guidelines/L5_RLC_
Circuits.pdf
13
Cambridge
TECHNICALS
Resources Link
Electric motors and generators
Description:
An introduction to how DC motors and generators
work. Includes animated diagrams.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.animations.physics.unsw.edu.au/jw/electricmotors.html
14
Cambridge
TECHNICALS
Resources Link
Types of DC Motor
Description:
An online tutorial introducing the different types of
DC motor and their configuration. Includes defining
equations and their application.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electrical4u.com/types-of-dc-motor-separately-excitedshunt-series-compound-dc-motor/
15
Cambridge
TECHNICALS
Resources Link
Types of DC generator
Description:
An online tutorial introducing the different types
of DC generator and their configuration. Includes
defining equations and their application.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electrical4u.com/types-of-dc-generators/
16
Cambridge
TECHNICALS
Resources Link
Starting of DC motor
Description:
An explanation of how a DC motor is started,
including relevant theory.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electrical4u.com/starting-methods-to-limit-starting-currenttorque-of-dc-motor/
17
Cambridge
TECHNICALS
Resources Link
Speed control methods of DC motors
Description:
An introduction to the various simple methods of
controlling the speed of a DC motor.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electricaleasy.com/2014/01/speed-control-methods-of-dcmotor.html
18
Cambridge
TECHNICALS
Resources Link
Single-phase power systems
Description:
An introduction to the advantages and limitations
of using single phase distribution systems.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_2/chpt_10/1.html
19
Cambridge
TECHNICALS
Resources Link
Three-phase power systems
Description:
A complementary introduction to three-phase
distribution systems.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_2/chpt_10/2.html
20
Cambridge
TECHNICALS
Resources Link
Three-phase electrical power
Description:
A useful overview of three-phase systems and their
circuit connections. Animated diagrams.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://en.wikipedia.org/wiki/Three-phase_electric_power#Generation_
and_distribution
21
Cambridge
TECHNICALS
Resources Link
Rectifier circuits
Description:
A full explanation of the function and application of
a range of DC diode rectifier circuits.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_3/chpt_3/4.html
22
Cambridge
TECHNICALS
Resources Link
Voltage regulators
Description:
A basic introduction to voltage regulators and
power supplies. Includes a block diagram.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electrical4u.com/regulated-power-supply/
23
Cambridge
TECHNICALS
Resources Link
Power supplies and load regulation
Description:
Explain the function and operation of stabilised
power supplies, including load regulation.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Online PDF
http://www.talkingelectronics.com/Download%20eBooks/Principles%20
of%20electronics/CH-17.pdf
24
Cambridge
TECHNICALS
Resources Link
Fuses and circuit breakers
Description:
A basic introduction to fuses. Also includes
discussion about circuit breakers and other forms of
circuit protection.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_1/chpt_12/4.html
25
Cambridge
TECHNICALS
Resources Link
Diodes
Description:
Explains how diodes can be used to protect a
circuit.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://jeelabs.org/2011/01/09/easy-electrons-%E2%80%93-diodes/
26
Cambridge
TECHNICALS
Resources Link
Analog(ue) vs Digital
Description:
A good basic explanation of the differences
between analog(ue) and digital circuits.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
https://learn.sparkfun.com/tutorials/analog-vs-digital/analog-and-digitalcircuits
27
Cambridge
TECHNICALS
Resources Link
Op Amps
Description:
A series of video tutorials introducing the characteristics,
configuration and operation of op-amps.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page with video tutorials
http://www.allaboutcircuits.com/videos/73.html
28
Cambridge
TECHNICALS
Resources Link
Op Amps – inverting and non-inverting
Description:
A series of tutorials explain the operation of inverting
and non-inverting op-amp circuits. Includes
characteristic equations and examples.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/opamp/opamp_2.html
29
Cambridge
TECHNICALS
Resources Link
The summing op-amp
Description:
A tutorial about the summing op-amp. Includes
characteristic equations.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/opamp/opamp_4.html
30
Cambridge
TECHNICALS
Resources Link
Online circuit simulator
Description:
Free online simulation package. Includes inverting,
non-inverting and summing op-amps. Can perform
simulation of other circuits, including digital circuits and
flip flops.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free, but requires setup of login. Some limitations
in free version.
Format:
Web page – online simulation tool
https://www.circuitlab.com/circuit/me84mf/op-amp-non-invertingamplifier/
31
Cambridge
TECHNICALS
Resources Link
Online op-amp simulator (from Texas Instruments)
Description:
Online simulation tool includes inverting and noninverting op-amps.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page – simulation tool
http://www.ti.com/lsds/ti/analog/webench/amplifiers.page
32
Cambridge
TECHNICALS
Resources Link
Introduction to digital logic gates
Description:
Complete set of tutorials covering digital logic gates and
types.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/logic/logic_1.html
33
Cambridge
TECHNICALS
Resources Link
Logic gate truth tables
Description:
A tutorial about logic gate truth tables. Also has an
introduction to Boolean algebra and expressions.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/boolean/bool_7.html
34
Cambridge
TECHNICALS
Resources Link
Converting truth tables to Boolean expressions
Description:
A tutorial explaining the relationship between truth
tables and Boolean expressions.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.allaboutcircuits.com/vol_4/chpt_7/9.html
35
Cambridge
TECHNICALS
Resources Link
Online logic simulator
Description:
Online logic simulator. Includes most popular logic
gates and flip flops. Combinational circuits can be
constructed and tested.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page – online simulation
http://www.neuroproductions.be/logic-lab/
36
Cambridge
TECHNICALS
Resources Link
Basic flip flops
Description:
An introduction to the four main type of flip flop –
including D and T types.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.circuitstoday.com/flip-flops
37
Cambridge
TECHNICALS
Resources Link
The D-Type flip flop
Description:
An introduction to the operation of the D-type flip flop.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.electronics-tutorials.ws/sequential/seq_4.html
38
Cambridge
TECHNICALS
Resources Link
JK and T type flip flops
Description:
Explanation of the operation of the JK and T type flip
flop. Includes circuit diagrams and truth tables.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Web page
http://www.brighthubengineering.com/diy-electronics-devices/46610jk-and-t-flip-flops/#imgn_1
39
Cambridge
TECHNICALS
Resources Link
Online simulation software
Description:
Online simulation software. Includes simulation of
analogue and digital circuits. Can also simulate flip flops.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free (but requires login). Free version limited to
circuits with 10 components.
Format:
Online simulation tool
http://www.docircuits.com/public-circuit/457/d-flipflop
40
Cambridge
TECHNICALS
Resources Link
Data sheets online
Description:
Online search engine of data sheets for electronic
components. Includes passive components
(eg resistors, capacitors inductors) and semiconductors
(eg op amps, logic gates, flip flops). Has links to a wide
range of manufacturers’ data sheets.
Supports:
OCR Cambridge Technicals in Engineering
Unit 4
Cost:
Free
Format:
Online search engine for data sheets
http://www.datasheetcatalog.com/
41
Cambridge
TECHNICALS
Resources Link
We’d like to know your view on the resources we produce. By clicking on the ‘Like’ or ‘Dislike’ button you
can help us to ensure that our resources work for you. When the email template pops up please add
additional comments if you wish and then just click ‘Send’. Thank you.
OCR Resources: the small print
OCR’s resources are provided to support the teaching of OCR specifications, but in no way constitute an endorsed teaching method that is required by the Board and the decision to use them lies with the individual teacher. Whilst every effort is made to ensure the accuracy of the content, OCR cannot be held
responsible for any errors or omissions within these resources. We update our resources on a regular basis, so please check the OCR website to ensure you have the most up to date version.
© OCR 2014 - This resource may be freely copied and distributed, as long as the OCR logo and this message remain intact and OCR is acknowledged as the originator of this work.
Cambridge
TECHNICALS
Contact us
Staff at the OCR Customer Contact Centre are available to take your call
between 8am and 5.30pm, Monday to Friday.
Telephone: 02476 851509
Email: vocational.qualifications@ocr.org.uk
43
Cambridge
TECHNICALS
Resources Link
For staff training purposes and as part of our quality assurance programme your call may be recorded or monitored.
© OCR 2014 Oxford Cambridge and RSA Examinations is a Company Limited by Guarantee. Registered in England.
Registered office 1 Hills Road, Cambridge CB1 2EU. Registered company number 3484466. OCR is an exempt charity.