BTEC National Diploma in Engineering

Unit 6 & 53 Combined

Electrical and Electronic Principles + Electronic Measurement and TestQualification BTEC National Diploma in

EngineeringAssessor Name

Paul Lewis

Unit Number

Learner Name

Achievement at a glance, deadlines given in module weeks, for example P1 should be completed by the 3 rd week of the module

Unit 6 Outcomes

P1 P2 P3 P4 P5 P6 P7 P8 P9 P10 P11 M1 M2 M3 D1 D2Tutor sign and date for each outcome achieved

Learner sign and date for each outcome submitted

Unit 53 Outcomes

P1 P2 P3 P4 P5 P6 P7 P8 M1 M2 M3 D1 D2Tutor sign and date for each achieved outcome

Learner sign and date for each submitted outcome

Delivery Schedule and Deadlines

Session Unit 6 Unit 53 DeadlineHand in by

Referred?Resubmit by

CompletedDate

1 P1 Session 32 P2 (part 1) “34 P2 (part 2) P2 & P3 (part1) Session 65 P4 “6 P6 Session 97 P5 “8 P5 P1 “9 P7 & P8 Session 1210 P10 & P11 ““11 P312 P4 & P5 Session 1513 P6 “14 P7 & P8 “15 P9 “16 M1 Session 2017 M2 “18 M3 “19 D1 “20 D2 “21 M1 Session 2522 M2 “23 M3 “24 D1 “25 D2 “

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………………………………………….

Session 1

Use DC circuit theory to calculate current, voltage and resistance in DC Networks

Unit 6 P1

For the circuit shown below: Circuit 1

Choose 5 different value resistors from the following table for resistors R1 – R5

Calculate the total power dissipation of your circuit then choose a suitable voltage from the table below based on this value

Resistor values for R1 – R5 Voltage values for V1

10 Ω 3 volts

22 Ω 5 volts

33 Ω 6 volts

47 Ω 9 volts

100 Ω 10 volts

220 Ω 12 volts

330 Ω 15 volts

470 Ω 24 volts

1k Ω

Calculate:

The total circuit resistance Rt

The total circuit current It

The current flowing through R3The voltage dropped across R2The power dissipated by R1Confirm the results of your calculation using the laboratory simulator (Multisim)

Care should be taken by each student to ensure that the combination of components and supply voltage are unique for each assessment.

Session 2

Unit 6 P2 (Part 1)Use a multi-meter to carry out circuit measurements in a DC circuit

You are required to construct the circuit used for P1 above. You are to use test equipment to carry out the following measurements as listed in the table below. You need to have the witness statement signed by the lecturer or trainer demonstrator.

Parameter Calculated values Measured values Simulated values

Total circuit resistance

Total circuit current

Current flowing through R3

Voltage dropped across R2

Power dissipated in R1

For this observation the learner:

Safely constructed a DC network comprising of 5 resistorsConnected the network to a DC source (5 volts)Correctly demonstrated the safe use of a multimeterUsed a multimeter to measure voltage, current and resistance in accordance with the set tasksWas able to contrast and compare the readings taken by a multimeter with calculated and simulated results

Signed Observer ……………………………….. Date …………………………….

Session 4

Unit 53 P2 (Part 1)

Describe the function, features and characteristics of a power supply

Produce an information sheet describing the functions, features and characteristics of the HQ PS1503SB Power supply.

Unit 53 P3 (Part 1) & Unit 6 (Part 2)

Use test equipment and measuring techniques to take measurements from a power supply (battery) and determine its internal resistance

Measure the offload voltage of a given battery using a multimeter

Measure the onload voltage of the battery when connected to the virtual cat circuit using a multimeter

Measure the current drawn by the virtual cat circuit using a multimeter

Use the data from the measurements to calculate the internal resistance of the battery

Include all of the above data in a technical report

Session 5

Describe the function and type of capacitors

Unit 6 P4

Describe the basic construction and function of a capacitor. This should include a labelled diagram of a capacitor showing the plates and dielectric, a circuit symbol, the unit of capacitance and a brief description of permittivity.

Describe the following list of capacitors in terms of their capacitance, typical range of working voltages, dielectric, and energy storage. Give one example of a typical application for each type of capacitor.

ElectrolyticMicaPlasticPaperCeramicFixed and variable

Session 6

Calculate the charge, voltage and energy values in a DC network for both three capacitors in series and three capacitors in parallel

Unit 6 P6

Choose 3 random capacitors from the following list and calculate the charge, voltage, capacitor and energy values stored by each capacitor for the following networks.

Choose from

100 nF, 1 uF, 10 uF, 22 uF, 33 uF, 47 uF, 100 uF

Session 7

Carry out and experiment to determine the relationship between voltage and current for a charging and discharging capacitor

Unit 6 P5

Choose a capacitor and resistor combination that will give a time constant between 1 – 5 seconds.

Tasks

Connect the circuit to the power supply as shown Calculate the time constant of the circuitSet up an oscilloscope to measure the voltage across the capacitor using suitable time and amplitude settingsSwitch on the circuit and measure the rise in capacitor voltage for 5 time constants. You can take a photo of this process to use as documentary evidenceSwitch off the circuit and measure the decay in capacitor voltage for 5 time constants. Once again you can use a photo as documentary evidenceShow how the rise in capacitor voltage is related to v =Vmax (1 – e –t/cr)Show how the decay in current is related to i = Imaxe-t/cr

Session 8

Unit 53 P1

Describe the function, features and characteristics of a measurement instrument

Task

1. Describe the function, features and characteristics of an oscilloscope.

Session 9

Unit 53 P2 (Part 2)

Describe the function, features and characteristics of a function generator

Unit 53 P7

Use a virtual measurement and test system to carry out a test on a piece of electronic equipment

For the following circuit

Set up the function generator to produce a sine wave with a frequency of 1 kHzSet the function generator how have an amplitude of 10 volts peak to peakConnect the function generator to the circuitSet up and oscilloscope to measure the input and output signalsWhen the oscilloscope is successfully measuring the input and output signals connect it to a computer via a USB cable and start up the virtual instrument softwareCompare the input signal to the output signal in terms of amplitude using the software cursorsAdjust the frequency of the function generator until the output signal = 0.7 times the input signalUse the software cursors to measure the phase angle at this point

Describe the process used to test the low pass filter and take measurements from it using the oscilloscope software controls on the computer. Photographs, illustrations, screen dumps and calculations are all required to complete this section

Unit 53 P8

Describe the measurement techniques, instrument connection, hardware and software used

Measurement techniques is a description of what values were measured and how the data was gathered. For example how the oscilloscope and function generator were set up to conduct the testInstrument connection deals with how the function generator was connected to your circuit, how the oscilloscope was connected to take measurements and how the oscilloscope was interfaced with the computer

You should give a brief description of the hardware and software used to carry out this test. Hardware to include the physical oscilloscope and computer. Software to include the OWON Virtual Oscilloscope

Session 10

Unit 6 P10

Use single phase AC circuit theory to determine the characteristics of a sinusoidal waveform

Sketch a sinuisoidal waveform then label and define the following parameters:

AmplitudeFrequencyPeriodic timeRMS valuePhase shift

Find the instantaneous voltage after 10 mS have elapsed for the following sine wave:

Vinst = 240Sin(100πt +/- 0)

Unit 6 P11

Use an oscilloscope to measure and determine the inputs and outputs of a single phase AC circuit

In conjunction with the data gathered for Session 9

Find the bandwidth for a low pass filter with the following components:

R = 1000Ω

C = 10 nF (0.00000001 Farads)

Simulate the circuit using Multisim and prove that your calculations are correct. Compare your calculated results with the simulation.

Session 11

Unit 6 P3

Compare the forward and reverse characteristics of two different semi-conductor diodes

You are required to use test equipment to measure the forward and reverse characteristics of two semi-conductor diodes. You should use a 1N4001 diode and a zener diode to carry out this experiment.

Tasks

Use the following circuit as a basis for this test:

Draw and label a diagram of the 1N4001 general purpose diode connected in forward bias and reverse bias modeMeasure the forward characteristic of the diode between 0.5 volts and 0.7 volts using steps of 0.01 of a volt by adjusting the resistance box R1Measure and record the reverse characteristic of the diode using Multisim between 49.9 volts and 50.01 volts using steps of 0.01 of a volt Carry out a similar experiment on a zener diode (of your choice) using its data sheet as a guide to the magnitude of voltages required to test its forward and reverse characteristicsDraw and label graphs of both data setsCompare the two graphs showing the conduction characteristics of both diodes, consult the data sheets and evaluate your findings in terms of forward and reverse voltages, power dissipation and maximum operating current

Session 12

Explain the importance of test specifications as an aid to ensuring the validity and consistency of

measurements

Unit 53 P4

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?

Define Validity and consistency.Explain why both are important parameters when taking measurements.Explain what a test specification isWhy is a test specification important in measurement taking?Use one of the Tasks in P3 as an example to showcase this

Unit 53 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:

Primary, secondary, working standards and SI unitsMetrology, calibration, accuracy, precision, sensitivity and resolutionA 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 interval3 reasons why calibration is normally carried out by specialist companiesThe effect that temperature and relative humidity can have on measurementsThe impact of calibration on quality, productivity and safety

Session13

Unit 53 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:

Precautions to be taken when working with live electrical equipmentProcedures 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 earthSafe isolation techniques for electrical/electronic equipmentHidden dangers of working with electronic equipment which has been safely isolatedThe importance of electrical safety cut-outs such as RCD’sRemoving and replacing inspection covers

Session 14

Unit 6 P7

Describe the characteristics of a magnetic field

Draw the magnetic field associated with a permanent bar magnet and use the diagram to carry out the following tasks.

Give 5 general properties of a magnetic field.Define flux, flux density and magnetic field strengthDescribe the effects of reluctance and hysteresis with respect to magnetic circuits.Define the term ferromagnetic and give three examples of a ferromagnetic materialDescribe the process and advantages of magnetic screening

Unit 6 P8

Describe the relationship between flux density (B) and field strength (H)

Plot the B/H curve on a suitable graph for the materials shown on the table from the given data and determine the relative permeability (µr) of the material for each stage. Given that µo = 4 x 10-7 H/m find the range of relative permeability for each material. Use the data plotted on the graph to analyse and explain the relationship between the two given materials in terms of flux density (B) and magnetizing force (H)Remember relative permeability µr = B/(H x µo)Plot the graph that shows relative permeability against the magnetizing forceDescribe what happens to a material as the magnetizing force is increased in terms of flux density and relative permeability

Magnetizing

Force (H) At/m

Mild steel

Flux density (B) Tesla’s

Cast Iron

Flux density (B)

Tesla’s

1000 0.7 0.3

2000 1.24 0.48

3000 1.45 0.6

4000 1.55 0.67

5000 1.6 0.72

Session 15

Describe the principles and applications of electromagnetic induction

Use the following tasks to describe the principles and applications of electromagnetic induction.

Define Faraday’ laws in your own words using diagrams where appropriate.Define Lenz’s law in your own words using diagrams where appropriate.Draw a diagram of a simple AC generator and use Fleming’s right hand rule to demonstrate the direction of the current in the rotating conductor when it is perpendicular to the North Pole.Explain the principle of operation of a simple transformer with reference to Faradays law of electromagnetic inductionExplain the principle operation of a 3 phase AC induction motor with reference to Faradays law of electromagnetic induction

Session 16

Unit 6 M1

Use Kirchoff’s laws to determine the current in various parts of a network having four nodes and the power dissipated in a load resistor containing two voltages sources

For the circuit shown below:

Use the same table as for Unit 6 P1 in order to choose component values.

Circuit 2

From the attached table choose different values for R1 – R3 From the attached table choose different voltages for V1 –V2Use Kirchoff’s laws to determine the current flowing through R1, R2 and R3Determine the power dissipation in R1

Use Multisim to confirm the results of your calculations and attach to the assignment as a screen dump

Session 17

Unit 6 M2

Evaluate capacitance, charge, voltage and energy in a network containing a series-parallel combination of three capacitors

Choose 3 random capacitors from the same table used for Unit 6 P6 and calculate the total capacitance, total charge, the voltage dropped across each capacitor and the total energy

stored for the following network.

Session 18

Unit 6 M3

Compare the results of adding and subtracting two sinusiodal AC waveforms graphically and by phasor diagram

V1 is a voltage of 15 V r.m.s at a phase angle of 25®, V2 is a voltage of 12 V r.m.s at a phase angle of -30®. Show the result of V1 + V2 and V1 - V2 graphically and by phasor diagram

Session 19

Unit 6 D1

Analyse the operation and the effects of varying component parameters of a power supply circuit that includes a transformer, diodes and capacitors

Tasks

Use an oscilloscope to measure the output voltage of this circuit at the point shownCompare the output voltage with the input voltage V1 (Screen dump)From you initial measurements use the graphing function in Multisim to measure the ripple voltage of this circuitAdjust R1 until the ripple voltage of the circuit reads 200 mVFrom your results calculate the time constant for this circuitIf R1 = 100Ω what value of capacitance would be required to produce a ripple voltage of 200 mV?If the instantaneous current conducted by the capacitor on its charge phase is I = C x dv/dt, find the repetitive forward current conducted by the circuit on each charge phase (use the grapher function)Explain the importance of the Vrrm rating when designing power supply circuits

Explain why the voltage rating of the capacitor and the diodes should be at least twice the V rrm rating given

Session 20

Task 14 (D2)

Evaluate the performance of a motor and a generator by reference to electronic theory

1) Draw and label the component parts of a basic DC machine.

2) Describe the action of a two segment commutator using appropriate diagrams.

3) Define:

a. Wave windingsb. Lap Windings

4) Briefly describe the operation of DC machines that are wound in:

a. Shuntb. Seriesc. Compound

5) Briefly describe armature reaction and show one way in which it can be overcome.

6) A 4 pole generator has a lap-wound armature with 50 slots with 16 conductors per slot. The useful flux per pole is 20 mWb. Determine the speed at which the machine must be driven to generate an e.m.f. of 300V.

7) A d.c. shunt-wound generator running at constant speed generates a voltage of 120 V at a certain value of field current. Determine the change in the generated voltage when the field current is reduced by 25%, assuming the flux is proportional to the field current.

8) With reference to the basic construction of a d.c. machine state the principle difference between a d.c. generator and a d.c. motor.

9) The armature of a d.c. machine has a resistance of 0.25 Ω and is connected to a 300 V supply. Calculate the e.m.f. generated when it is running:

a. as a generator giving 100 Ab. as a motor taking 80 A

Session 21

Unit 53 M1

Explain the importance of resolution, accuracy, sensitivity bandwidth and input impedance on the performance of a piece of test equipment

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

Session 22

Unit 53 M2

Use a manufacturer’s recommended procedure together with laboratory instruments and standards to calibrate and configure an item of electronic test equipment

Use the manufacturer’s recommended procedure to calibrate and configure a laboratory oscilloscope.

Use the calibrated scope to check the accuracy of a laboratory function generator with respect to frequency and amplitude.

Check the accuracy of your measurements against that given by the manufacturer of the function generator.

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.

Session 23

Task 10 (M3)

Use appropriate software to display and analyse voltage/time data captured from a virtual oscilloscope

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

Session 24

Unit 53 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

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.

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?

Session 25

Unit 53 D2

Devise and demonstrate a calibration procedure for an item of electronic test equipment

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.