BTEC National Diploma in Engineering
Unit 53
Electronic Measurement and Testing
Qualification BTEC National Diploma in
Engineering
Unit
Unit 53
Electronic Measure and Test
Number
Assessor
Name
Learner Name
Paul Lewis
Achievement at a glance, deadlines given in module weeks, for example P1 should be completed by the 3rd week of
the module.
P1
P2
P3
P4
P5
P6
P7
P8
M1
M2
M3
D1
D2
Year
2
Year
2
Year
2
Year
2
Year
2
Tutor sign and date for each achieved outcome
MW
3
MW
3
MW
9
MW
10
MW
11
MW
12
MW
6
MW
6
Learner sign and date for each submitted outcome
Learner Declaration
I confirm that the work submitted to complete the given tasks is my own. I have indicated where research and other resources have been used to
confirm the conclusions reached within the submission and listed those resources in a bibliography.
Sign………………………………………………… Date………………………………………….
Task 1 (P1)
Describe the function, features and characteristics of a measurement instrument
Check the following
Yes
No
Have you included documentary evidence such as a drawing,
illustration or photograph which you can label and indicate the
function of the various buttons and dials?
Have you fully described the features of an oscilloscope e.g. its input
and output connectors?
Have you described the importance of the characteristics of an
oscilloscope such as its input and output impedance, bandwidth and
accuracy?
Task
1. Describe the function, features and characteristics of an oscilloscope.
Task 2 (P2)
Describe the function, features and characteristics of three different pieces of electronic test equipment
Check the following
Yes
No
Have you included documentary evidence such as a drawing,
illustration or photograph which you can label and indicate the
function of the various buttons and dials?
Have you fully described the features of test equipment such as
function generators e.g. such as its portability or in built calibration
facilities
Have you described the importance of the characteristics of test
equipment such as its input and output impedance, bandwidth and
accuracy?
Tasks
Describe the function, features and characteristics of the following three pieces of electronic test
equipment.
1. A function generator
2. A power supply
3. A logic probe
Task 3 P3
Use test equipment and measuring techniques to take measurements from three different pieces of
electronic equipment
This is a complex task that is split into 3 parts.
P3 Part 1 Practical Task and written report
Construct the circuit below
1. Connect the function generator and oscilloscope as shown
2. Set the function generator to give a sine wave output with a frequency of 1 kHz and an
amplitude of 10 volts peak to peak
3. Set up the oscilloscope to measure and compare the input and output
4. Measure and record the input and output for this circuit (screen dump, photo)
5. Using the equation FrequencyCUTOFF = 1/(2πcr) find the cut-off frequency for this circuit
6. Adjust the function generator to give the output frequency and use the oscilloscope to measure
and record it (screen dump, photo)
7. Write a brief report on your findings including the differences between both amplitude and
phase of the input and output waveforms at the cut-off frequency
P3 Task 2
Choose a resistor and capacitor combination that gives a time constant between 1 – 5 seconds and
construct the circuit shown below. Please note that the component shown do not give the correct time
constant.
Tasks
1. Use the following equation Vinst =Vsupply(1 – e-t/CR) to predict the time at which the voltage across
the capacitor will be at 10% and 90% of its maximum value
2. Connect the power supply (12 volts) and use an oscilloscope to measure the change in voltage
across the capacitor over a period of 5 time constants. Freeze the display
3. Measure the rise time of this voltage (rise time is measured between 10% and 90% of the
minimum and maximum voltages) you will need to use the cursor controls to get an accurate
reading
4. Relate your measured results to the values predicted by the given equation
5. Write a brief report on this experiment including a circuit diagram, relevant screen dumps,
calculated and measured results and an evaluation
P3 Task 3
The purpose of this task is to find the unknown internal resistance of a battery using 2 multi-meters and
applying Ohm’s law.
1. Use a multi-meter to measure the off load voltage of a given battery. A 9 volt battery is used for
this example. Note the voltage
2. Now set up the circuit shown below to measure the voltage drop across the electrical load
(called the on load voltage) and the current drawn by the circuit.
This is the resistance you are trying to find
3. Use the following equation to calculate the approximate internal resistance of the battery
4. Include your findings in a brief report including a photo of the circuit set up and a short
evaluation. The evaluation should include the reasons why a voltmeter always measures voltage
in parallel and an ammeter always measure current in series
Task 4 (P4)
Explain the importance of test specifications as an aid to ensuring the validity and consistency of
measurements
Scenario
Imagine you are an Electronics company manager; you have just designed and built a prototype circuit
that meets your client’s specifications. They request an order of 1,000 circuits to be made. To deal with
this demand you enlist a team of test engineers. You need some way of ensuring that the tests to be
carried out will get the results that meet the specification. How can you ensure they get valid and
consistent measurements every time?
Aims and objectives
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Define Validity and consistency.
Explain why both are important parameters when taking measurements.
Explain what a test specification is
Why is a test specification important in measurement taking?
Use one of the Tasks in P3 as an example to showcase this.
Task 5 (P5)
Describe the principles and need for the calibration of an item of electronic test equipment
Produce a report highlighting the reasons why electronic test and measurement equipment needs to be
calibrated on a regular basis. Your report should include references to:
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Primary, secondary, working standards and SI units
Metrology, calibration, accuracy, precision, sensitivity and resolution
A reasonable calibration interval for equipment in regular use (4+ hours per day)
3 reasons why an instrument might need to be calibrated within the calibration interval
3 reasons why calibration is normally carried out by specialist companies
The effect that temperature and relative humidity can have on measurements
The impact of calibration on quality, productivity and safety
Task 6 (P6)
Describe the health, safety and configuration issues that need to be considered when connecting test
equipment to an item of electronic equipment that needs testing
Scenario
You have been employed as a junior electrical/electronic technician for a small local firm specializing in
the repair, installation and commissioning of direct online starting equipment for small to medium
power electrical motors.
One of your best customers has a motor starter which has developed a fault. You have been tasked with
finding the fault and testing the equipment before handing it back to the client. The motor will need to
be tested using a 440 volt 3 phase supply.
Describe the procedures you would take to ensure that this equipment can be tested safely. You
description could include illustrations, diagrams and examples from industry. Here are some of the areas
you should include:
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Precautions to be taken when working with live electrical equipment
Procedures which ensure that electrical/electronic test equipment is suitable and safe for use
with live electrical equipment (use of manuals and manufacturer’s procedures)
The importance of checking that electrical equipment is properly bonded to earth
Safe isolation techniques for electrical/electronic equipment
Hidden dangers of working with electronic equipment which has been safely isolated
The importance of electrical safety cut-outs such as RCD’s
Removing and replacing inspection covers
Task 7
P7 Use a virtual measurement and test system to carry out a test on piece of electronic equipment
You have a choice of using either P3 part 1 or 2, or the LM386 amplifier build and test as a basis for this
outcome. Your report should include:
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

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A description of the test carried out
A circuit diagram showing the test points
A brief description of the test and measurement equipment used
A detailed oscilloscope screen dump, properly labelled showing the outcome of the test
P8 Describe the measurement techniques, instrument connection, hardware and software used
Check the following
Have you described the type of virtual oscilloscope used to
carry out this task?
Have you listed the system requirements needed to run this
virtual measurement and test system (processor speed,
bandwidth, ram, operating system, bus capability)
Have you provided screen dumps showing how you set up the
virtual scope to capture data from the test?
Have you described or demonstrated how data can be stored
from the test?
Yes
No
1. You can reproduce either task 1 or 2 from P3 to complete this outcome using a virtual
oscilloscope. Make sure you have covered the points in the table.
Task 8 (M1)
Explain the importance of resolution, accuracy, sensitivity bandwidth and input impedance on the
performance of a piece of test equipment
Assessor Feedback
Achieved?
Explain the importance of resolution, accuracy, sensitivity bandwidth and input impedance on the
performance of an oscilloscope. You can use any of the tests in the pass section (which required an
oscilloscope) as a basis for your submission, especially the tasks carried out for P3
Task 9 (M2)
Use a manufacturer’s recommended procedure together with laboratory instruments and standards to
calibrate and configure an item of electronic test equipment
Assessor Feedback
Achieved?
1. Use the manufacturer’s recommended procedure to calibrate and configure a laboratory
oscilloscope.
2. Use the calibrated scope to check the accuracy of a laboratory function generator with respect
to frequency and amplitude.
3. Check the accuracy of your measurements against that given by the manufacturer of the
function generator.
4. Based on your findings, would you recommend that the function generator needs to be sent
back to the manufacturer for calibration? You need to justify this recommendation.
Task 10 (M3)
Use appropriate software to display and analyse voltage/time data captured from a virtual oscilloscope
Assessor Feedback
Achieved?
1. This is a natural extension of the task given for P7. In this case you are required to analyse a
waveform. The best way to accomplish this is to use either task 1 or 2 for P3 as a basis for
comparing the captured data with the results predicted by theory
Task 11 (D1)
Evaluate the accuracy of your own test measurements and relate them to limitations of the test
equipment, test procedures or possible emergent fault conditions
Assessor Feedback
Achieved?
1. You can use any of the tests carried out in the various exercises or practical projects as a basis
for this evaluation. The submission needs to be an ‘in-depth’ investigation of the effects of
connecting test/measurement equipment to a circuit under test and how the results are limited
by the characteristics of the test equipment and test procedures.
2. As an example, an oscilloscope is incapable of accurately displaying a transient pulse due to its
finite bandwidth. This could be the basis of an investigation carried out by you to explain why?
Task 12 (D2)
Devise and demonstrate a calibration procedure for an item of electronic test equipment
Assessor Feedback
Achieved?
1. Devise and demonstrate a calibration procedure for a x10 oscilloscope probe to be used with
the laboratory oscilloscopes. Explain why the probe needs to be calibrated and under what
circumstances such a probe might be required in preference to a standard x1 probe.