BTEC National Diploma in Engineering

BTEC National Diploma in Engineering

Unit 60

Electronic Fault Finding

Qualification / BTEC National Diploma in Engineering / Assessor Name / Paul Lewis
Unit Number / Unit 60
Electronic Fault Finding / Learner Name

Achievement at a glance, deadlines given in module weeks, for example P1 should be completed by the 2ND week of the module.

P1 / P2 / P3 / P4 / P5 / P6 / P7 / P8 / M1 / M2 / M3 / D1 / D2
Tutor sign and date for each achieved outcome
MW
2 / MW
4 / MW
5 / MW
7 / MW
9 / MW
10 / MW
12 / MW
12 / MW
20 / MW
20 / MW
20 / MW
20 / MW
20
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………………………………………….

Unit Scenario

You have been employed by a local electronics company which specializes in the manufacture of circuits which can be used to control the temperature within a room (such as a greenhouse). Recently, there have been reports of circuit malfunction from several users which has led to costly ‘on-site’ repairs needing to be made by the manufacturer. To combat this, your line manager has commissioned you to draw up a fault location strategy which can be used safely by qualified personnel to identify, isolate and repair the system. Before the fault location strategy can go ‘live’ you will be required to demonstrate its use to your line manager.

All of the pass outcomes for this unit can be achieved by completing the tasks on the circuit shown below. This circuit has both analogue and digital elements which are required to satisfy the grading criteria.

Space Temperature Control Circuit

Important

The first thing you should do is to draw this circuit out neatly in pencil on A3 paper. Leave plenty of space around the margins for component labelling and signal identification.

Read a circuit diagram for an electronic system and identify two different types of analogue circuit, the components that make up each circuit and the circuit input and output signals.

Check the following / Yes / No
Have you redrawn the circuit neatly?
Have you outlined/highlighted both of the analogue circuits present in this schematic and named them?
Have you identified the components which make up both circuits
Have you indicated the expected power voltage levels required for both circuits?
Have you drawn or shown the expected input and output signal levels for this circuit?
Assessor Feedback / Achieved?

Read a circuit diagram for an electronic system and identify two different types of digital circuit, the components that make up each circuit and the circuit input and output signals.

Check the following / Yes / No
Have you redrawn the circuit neatly?
Have you outlined/highlighted both of the digital circuits present in this schematic and named them?
Have you identified the components which make up both circuits
Have you indicated the expected power voltage levels required for both circuits?
Have you drawn or shown the expected input and output signal levels for this circuit?
Assessor Feedback / Achieved?

Prepare a written fault location strategy for a given analogue electronic system and identify the fault-finding and signal tracing techniques to be applied.

Check the following / Yes / No
Your fault finding strategy should use a range of techniques (physical inspection, pull test, component identification, input to output signal tracing, half split signal tracing, a list of common faults and their symptoms)
You should redraw both analogue circuits and identify test points, expected voltage/current levels and the type of test equipment to be used. (oscilloscope, multi-meter, logic probe)
You should use component data sheets to identify the ‘pin-out’ diagrams and power requirements for any chips used in the circuits. (LM35, LM358)
Your fault-finding strategy should wherever possible include the use of fault finding aids such as functional charts, diagrams, trouble shooting charts and component data sheets.
Your fault-finding strategy must be safe.
Assessor Feedback / Achieved?

Prepare a written fault location strategy for a given digital electronic system and identify the fault-finding and signal tracing techniques to be applied.

Check the following / Yes / No
Your fault finding strategy should use a range of techniques (physical inspection, pull test, component identification, input to output signal tracing, half split signal tracing, a list of common faults and their symptoms)
You should redraw both digital circuits and identify test points, expected voltage/current levels and the type of test equipment to be used. (oscilloscope, multi-meter, logic probe)
You should use component data sheets to identify the ‘pin-out’ diagrams and power requirements for any chips used in the circuits. (LM311, 74LS02)
Your fault-finding strategy should wherever possible include the use of fault finding aids such as functional charts, diagrams, trouble shooting charts and component data sheets.
Your fault-finding strategy must be safe.
Assessor Feedback / Achieved?

Use test instruments to identify fault conditions within an analogue system that has at least one faulty circuit and one component fault.

Collect and record the test data from an analogue electronic system fault-finding test and prepare a report.

To achieve both outcomes you will need to use your written fault location strategy to identify a faulty circuit and faulty component on a real circuit during a practical demonstration. The practical demonstration will form the basis of your report which should record in detail the following:

Your name and the date of the test
A description of the function of each system
The test conditions and the methods used to carry out the tests
A table listing all the tests undertaken along with the results
Your comments and recommendations based on the outcome of the tests

Select and use test instruments to identify fault conditions within a digital electronic system that has at least one faulty circuit and one component fault.

Collect and record the test data from a digital electronic system fault-finding test and prepare a report.

Collect and record the test data from an analogue electronic system fault-finding test and prepare a report.

Your name and the date of the test
A description of the function of each system
The test conditions and the methods used to carry out the tests
A table listing all the tests undertaken along with the results
Your comments and recommendations based on the outcome of the tests

Witness Statement P5 & P7

The learner ...... has successfully located one faulty component and identified one faulty circuit within the analogue elements of the given circuit. This was completed in accordance with the requirements of a fault location strategy prepared by the learner.

The learner has produced a full report on the test procedure used which includes all of the required elements listed and has achieved the stated outcomes.

Signed Assessor ...... Date ......

Witness Statement P6 & P8

The learner ...... has successfully located one faulty component and identified one faulty circuit within the digital elements of the given circuit. This was completed in accordance with the requirements of a fault location strategy prepared by the learner.

The learner has produced a full report on the test procedure used which includes all of the required elements listed and has achieved the stated outcomes.

Signed Assessor ...... Date ......

Compare the circuit diagrams of two different approaches to the same type of circuit.

This outcome can be achieved in several different ways. Firstly there is often more than one way of achieving a desired ‘electronic’ outcome. Within the given circuit there are several elements which could be done differently. Indeed there are better more modern methods available for making circuits such as this which require fewer components.

Your task is to choose one of those elements and show how its function could be achieved using another circuit. You could of course attempt to show how the entire circuit function can be achieved using different circuits.

Evaluate a fault location strategy and make recommendations for improvement.

This evaluation should form a separate section of your report for either the analogue or digital elements of the circuit. As with all evaluations it should detail the things that went well, what did not go so well and what you would do differently next time.

Justify the choice of test instruments selected to identify fault conditions within an electronic system.

This should form a separate section of your report. As a simple example of justification you could choose to explain why an oscilloscope is better suited for reading electronic information that changes quickly (e.g. a waveform) in preference to a multi-meter. Justification can also encompass things such as tolerances, accuracy, cost, time required, training needed, safety and equipment availability.

Evaluate a circuit diagram for an electronic system and identify incorrect circuit/input-output signals.

This outcome will form a separate part of the practical demonstration where you will be asked a series of questions based on the given circuit related to the outcome criteria. In order for you to achieve this outcome you must fully record all of the details within your report. So make sure that you take notes during the practical demonstration.

Examine the fault conditions within an electronic system that presents a fault in more than one circuit.

A common example of this type of fault happens when a power supply in unable to supply enough current to power and entire circuit. Once this happens the output voltage of the power supply falls leading to circuit failure across the system.

To achieve this outcome you will be asked a series of questions related to the assessment criteria during your practical demonstration. In order to achieve this outcome you must fully record the details within your report. Make sure you take notes during the practical demonstration.