Understand the operating principles of transformers

1. Understand the operating principles of transformers

2. P&P2EL Electromagnetic induction P&P2EL Transformers Understand the operating principles of transformers Modules Topics Notional Hours 4 18 8 30 TE221 Electromagnetic induction TE221 Transformer calculations TE221 Eddy currents Total Notional Hours

3. Critical Cross-field Outcomes Identify and solve problems Work effectively with others Communicate effectively Organise and manage myself and my activities Collect, analyse, organise and critically evaluate information Use science and technology effectively and critically Demonstrate an understanding of the world as a set of related systems Use mathematics Learner and societal development US: 10719 Understand the operating principles of transformers TE221 Electromagnetic induction Understand the impact of various factors on the current generated when a conductor is moved through a magnetic field Understand the result of a conductor being moved through a magnetic field Understand the definitions, symbols, units of measurement and basic terminology used in electricity and magnetism

4. Notional Hours 4 Topic Specification: TE221 Electromagnetic induction Learning Activities Assignment Description Topic assessment criteria Use Multi media WHAT • The assessor will observe and confirm that learners: • Understand the principles of a magnetically induced current • Understand how various factors impact on the current generated when a conductor is moved through a magnetic field A group or individual exercise of viewing video material on transformer principles. Group experimental set-up to demonstrate that a current is generated when a conductor is moved through a magnetic field. Self Study Field visits Collect Information Media search Interview experts Attend lectures HOW Group Discussions Sketch • A simple experiment is set up where a circuit is attached to an multimeter and a magnet is used to induce a current • Indicate the effect of reversing the magnetic poles, varying the speed at which the conductor is moved through the field and adding some loops to create a loose coil with the conductor. • Learners write a short report in which the experiment is sketched (with captions) and tabled for assessment. Case studies Analyse, plan and make decisions Use checklists Develop recommendations Job assignment Make sketch Complete documents Execute, test and evaluate Draft a report Complete a test/questionnaire

5. Critical Cross-field Outcomes Identify and solve problems Work effectively with others Communicate effectively Organise and manage myself and my activities Collect, analyse, organise and critically evaluate information Use science and technology effectively and critically Demonstrate an understanding of the world as a set of related systems Use mathematics Learner and societal development US: 10719 Understand the operating principles of transformers TE221 Transformer calculations Be able to calculate primary and secondary transformer circuit parameters Understand the basic symbols and formulas used in transformer calculations Understand the operating principles of a simple transformer Understand the impact of alternating current on an electromagnet

6. Notional Hours 18 Topic Specification: TE221 Transformer calculations Learning Activities Assignment Description Topic assessment criteria Use Multi media WHAT • The assessor will observe and confirm that learners: • Understand the impact of alternating current on an electromagnet • Understand the operating principles of a simple transformer • Understand the basic symbols and formulas used in transformer calculations • Are able to do basic transformer calculations Learners attend a short lecture in which transformer calculation methods are explained Learners prepare a transformer poster which is used to explain transformer operating principles to the group Learners use self study material related to transformer principles Self Study Field visits Collect Information Media search Interview experts Attend lectures Group Discussions HOW Sketch • Learners prepare a poster to assist them to explain the operation of a transformer • Each learner get the opportunity to present to the group: • the impact an alternating current will have on the transformer core • the basic operating principle of transformers • the transformer relationship formulas • Learners solve a number of given transformer problems • Learners complete a test in which understanding of transformer calculations and principles are demonstrated Case studies Analyse, plan and make decisions Use checklists Develop recommendations Job assignment Make presentation Complete documents Execute, test and evaluate Draft a report Complete a test

7. Critical Cross-field Outcomes Identify and solve problems Work effectively with others Communicate effectively Organise and manage myself and my activities Collect, analyse, organise and critically evaluate information Use science and technology effectively and critically Demonstrate an understanding of the world as a set of related systems Use mathematics Learner and societal development US: 10719 Understand the operating principles of transformers TE221 Eddy Currents Understand how eddy currents influence the efficient operation of a transformer and how it can be counteracted Understand the impact of eddy currents on the moving conductor and how this can be countered by cutting slots in the conductor Understand the occurrence of eddy currents in a flat conductor moved through an electric field

8. Notional Hours 8 Topic Specification: TE221 Transformer principles Learning Activities Assignment Description Topic assessment criteria Use Multi media Learners have a group discussion to try and explain the phenomena of eddy currents in transformer cores Learners are supplied with a small transformer (e.g. charger) to view An exercise to view video material on eddy currents in transformers. WHAT • The assessor will observe and confirm that learners: • Understand the occurrence of eddy currents in a flat conductor moved through an electric field • Understand the impact of eddy currents on a flat moving conductor and how this can be countered by cutting slots in the conductor • Understand how eddy currents influence the efficient operation of a transformer and how it can be counteracted Self Study Field visits Collect Information Media search Interview experts Attend lectures HOW Group Discussions • The fact that eddy currents are generated in a flat conductor moved through a magnetic field is explained to learners. • In a group discussion learners should try to explain why the eddy currents are generated and how cutting slits in the conductor will minimise the effect • A simple transformer is passed around to show its construction – especially the insulated core leaves • Continue the discussion by having the group discuss and summarise why the core is produced from insulated leaves • Learners view video material to confirm the principles discussed • A multiple choice questionnaire is used to confirm understanding Educational games Case studies Analyse, plan and make decisions Use checklists Develop recommendations Job assignment Make presentation Complete documents Execute, test and evaluate Draft a report Complete a test/questionnaire