Soft Copy email to [[email protected]] All students are advised to keep a duplicate copy of all work submitted for reference. Please keep this cover and any marked pages! 學生姓名 Student Name : 聯絡電話 Contact Number : 電郵地址 Email Address : 課程名稱 Program Name : * Please
HND in Cons HND in BSE HND in Civil 科目名稱及編號 Module Code & Name : Unit 50 Electrical Installation for Building Services Engineering 講師姓名 Lecturer : Mike Chan / Dr. Kwan 第一次上課日期 1st lesson Date: 26/3/2015 派發日期 Issued Date: 16/4/2015 遞交限期 Submission Deadline : First Submission:28/5/2015; Final Submission:16/7/2015 遞交日期 Submission Date : 功課交收紀錄 Assignment Submission Records Attention  All assignments need to be submitted within 90days after distribution.  If needed, students can apply for a 30-day extension to the college's staffs. (ONLY 1 extension per module)  Deferral application form should be handed in 10 days before deadline.  To be efficient, please keep this cover and the marked pages after amendment.  Late submission is not allowed. Any late submission will be charged HK$500 administration fee and students need to redo the new term's assignment in the next intake.  All assignments must be submitted in both hard and soft copies (USB) or email to [email protected]  No plagiarism is allowed. If there is any plagiarism found, we will follow the procedures stated in the admission pack. If you have any enquiries, please feel free to contact our staffs. Submission Requirement Font Times New Roman Font Size 12 Spacing Single Line Spacing Margin 2 Centimetres (Left-side of page only) Printing Single Sided Number of Words (Approx.) 7,500 words 學生 / 導師交回功課 Submission or Take Away 日期 Date 負責職員簽處 Staff Signature 1. Student – 1st Submission 2. Lecturer – 1st Take Away 3. Lecturer – 1st Marking Completed 4. Student – 1st Take Away (Amendment) 5. Student – 1st Amendment Completed 6. Lecturer – 2nd Take Away 7. Lecturer – 2nd Marking Completed 8. Student – 2nd Take Away (Amendment) 9. Student – 2nd Amendment Complete 10. Lecturer – 3rd Take Away 11. Lecturer – 3rd Marking Completed 12. Student – 3rd Take Away (Amendment) 13. Student – 3rd Amendment Completed 14. Lecturer – 4th Take Away 15. Lecturer – 4th Marking Completed Marking *FOR REFERENCE ONLY Task Subtask 1.1 1.2 1.3 1.4 1.5 1 Comment: 2.1 2.2 2.3 2.4 2.5 2 Comment: 3.1 3.2 3.3 3.4 3.5 3 Comment: 4.1 4.2 4.3 4.4 4.5 4 Comment: 5.1 5.2 5.3 5.4 5.5 5 Comment: 6.1 6.2 6.3 6.4 6.5 6 Comment: 7.1 7.2 7.3 7.4 7.5 7 Comment: *Please
below if achieved. M1 M2 M3 D1 D2 D3 Overall Grade Marker Signature * Grading will not be accepted if there is no signature by the Marker. Assessor's comments Qualification Assessor name Unit number Learner name Assignment title Grading criteria Achieved? Learner feedback Assessor feedback Action plan Assessor signature Date Learner signature Date (For College Internal Only) INTERNAL VERIFICATION – ASSESSMENT DECISIONS Award Assessor Unit(s) Unit 50 Electrical Installation for Building Services Engineering Assignment title: Unit 50 Electrical Installation for Building Services Engineering Learner's name: Which criteria has the assessor awarded? Pass Merit Distinction Do the criteria awarded match those targeted by the assignment brief? Y/N* Details Has the work been assessed accurately? Y/N* Details Is the feedback to the learner: • Constructive • Linked to relevant grading criteria • Identifying opportunities for improved performance Y/N* Details Does the grading decision need amending? Y/N* Details Remedial action taken: Internal Verifier name Internal Verifier signature Date Confirm Action completed Assessor signature Internal verifier signature Assignment front sheet Learner name Assessor name Mike Chan/ Dr. Kwan Date issued Completion date Submitted on Qualification Unit number and title HND in Construction and the Built Environment (Building Services Engineering) Unit 50 Electrical Installation for Building Services Engineering Assignme nt title Unit 50 Electrical Installation for Building Services Engineering In this assessment you will have opportunities to provide evidence against the following criteria. Indicate the page numbers where the evidence can be found. Criteria referenc e To achieve the criteria the evidence must show that the student is able to: Task no. Evidenc e P1.1 Use maximum power transfer theorem and Thevenin's and Norton's models to solve practical problems 1.1 P1.2 Calculate the parameters of AC equivalent circuits using transformation theorems 1.2 P1.3 Apply circuit theory techniques to solve AC circuit problems 1.3 P1.4 Analyse the application and benefits of power factor control 1.4 P1.5 Apply complex quantities techniques to solve complex power and AC circuit problems 1.5 P2.1 Evaluate the appropriateness of designs in relation to environmental, access and health, safety and welfare issues 2.1 P2.2 Analyse how design constraints for a given building affect the choice of electrical distribution 2.2 P2.3 Apply'designer's discretion' when producing electrical designs for buildings 2.3 P2.4 Evaluate the appropriateness of electrical designs in terms of complying with current standards and legislation 2.4 P2.5 Determine optimum cable sizes for groups of cables with different cross-sectional areas and load characteristics 2.5 P3.1 Examine DC series and shunt motor applications 3.1 P3.2 Explain how to control the speed of DC series motors using thyristor control 3.2 P3.3 Calculate the theoretical ratings of motors for a given duty 3.3 P3.4 Explain starting methods and speed control for AC motors 3.4 P3.5 Evaluate the suitability of AC motors for building services applications 3.5 P4.1 Describe the operation of half-wave and full-wave rectification systems 4.1 P4.2 Explain the effect of using controlled rectifiers in AC circuits 4.2 P4.3 Examine the application of rectification in the control of electrical plant and equipment 4.3 M1 Identify and apply strategies to find appropriate solutions: an effective approach to research and study has been applied 1.4 M2 Select/design and apply appropriate methods/techniques: the selection of methods and techniques/sources has been justified. 2.4 M3 Present and communicate appropriate findings: appropriate structure and approach has been used 3.5 D1 Use critical reflection to evaluate own work and justify valid conclusions: the validity of results has been evaluated using defined criteria 2.2 D2 Take responsibility for managing and organizing activities: autonomy and independence has been demonstrated 2.5 D3 Demonstrate convent/lateral/creative thinking: self-evaluation has taken place 4.3 Learner declaration I certify that the work submitted for this assignment is my own and research sources are fully acknowledged. Learner signature: Date: Assignment brief Qualification HND in Construction and the Built Environment (Building Services Engineering) Unit number and title Unit 50 Electrical Installation for Building Services Engineering Start date 26/3/2015 Deadline First Submission:28/5/2015; Final Submission:16/7/2015 Assessor name Mike Chan / Dr. Kwan Assignment title Electrical Installation for Building Services Engineering The purpose of this assignment is to: Outcome 1: Be able to solve DC and AC network circuit problems Outcome 2: Be able to apply current standards and legislation to building electrical systems Outcome 3: Understand DC and AC motors Outcome 4: Understand rectification systems for controlling electric plant and equipment. Task 1 DC & AC networks circuit problem Express your view, with illustrations by drawing(s), and justification, on each of the following: Task 1.1 (P1.1) For the AC circuit shown in the figure below, determine the value of the load impedance, ZLD, connected across the point a, b, will result in maximum power transfer from the source. You need to find either Thevenin's or Norton's equivalent circuit first. Task 1.2 (P1.2) Find the Wye equivalent for the Delta connected circuit shown below. Task 1.3 (P1.3) Use the node voltage method to find the steady-state expression for io , in the circuit shown in the figure below. Given ig = 5 cos 2500t A vg = 20 cos (2500t + 90°) V. Task 1.4 (P1.4) Explain briefly what power factor correction is and what benefits can be accomplished by this measure. Task 1.5 (P1.5) Calculate the real and reactive power associated with each circuit element in the circuit below. Task 2 Apply Current Standards and Legislation to Building Electrical Systems Task 2.1 (P2.1) The following is the proposed floor plan for an e-Commerce company. Evaluate the appropriateness of designs in relation to environmental, access and health, safety and welfare issues Task 2.2 (P2.2) An Electrical Services Designer needs to provide electrical power distribution to a 16-storey residential building. All the tenants do not need three-phase power provision. However, the local electrical utilities substation can only provide a three-phase 380V main income supply to the building. The Designer also understands that the IEE Regulations, stipulate that where fixed live parts between which there is more than 250V are inside enclosures, which although separate from each other , but are within 2 meter of each other, a notice must be displayed giving warning of the maximum voltage between the live parts. Provide an analysis to address how design constraints for this building affect the choice of electrical distribution. Task 2.3 (P2.3) Consider an installation with two motors of the same type installed in different applications. One motor is used in a supply air fan, the other in a passenger lift application. Both motors have a 20 kW motor with a full load running current of 35 amps and a starting current of 175 A. However, the load characteristics for the two motors are markedly different. The figure below shown the starting and running currents of lift motor and fan motor between 9.00 am and 9.30 am. Base on the given information, apply designer's discretion to determine the power supply cable capacity required for the lift motor and the fan motor respectively. Assume the starting time of the lift motor is 30 s. Task 2.4 (P2.4) Evaluate the appropriateness of final circuit design shown in the figure in terms of complying with BS 7671 IEE Wiring Regulations. Given the line voltage is 220 V in Hong Kong, and the voltage drop of the cable is 29 mV/A/m. Task 2.5 (P2.5) Consider a 50 kW, three phase load at 0.8 power factor. The load is to be supplied by a cable to be run underground for 50 m and clipped to cable tray for a further 50 m together with 5 other similar cables. Overload protection is to be provided by a BS 88 fuse. It is assumed that the grouped cables may be subject to simultaneous overload. Determine the optimum cable size for this three phase load following BS7671 guidelines. Task 3 Understand DC and AC motors Task 3.1 (P3.1) Compare the torque speed characteristics of DC series and shunt motor, and suggest the applications suitable for each type. Task 3.2 (P3.2) Explain the DC series motor speed control mechanism using solid state control rectifiers. Task 3.3 (P3.3) Calculate the theoretical rating of a motor, which has a duly cycle of 3.0 kW for 2 min, 5 kW for 2 min , 8 kW for l min and stopped for 4 min. Task 3.4 (P3.4) (a) Explain any TWO starting methods for three phase induction motors. (b) Describe how to accomplish speed control in three phase induction motors. Task 3.5 (P3.5) In Hong Kong, most of the 3-phase AC motors in buildings are fitted to fans and pumps. Evaluate the suitability of AC motors for building services applications in terms of energy efficiency. You should address the contribution of modern electronic speed controllers in your discussion. Task 4 Understand Rectification Systems for Controlling Electric Plant and Equipment Task 4.1 (P4.1) With the use of suitable circuit and waveform diagrams, describe the operation of (a) a diode half-wave, and (b) a full-wave rectifier. Task 4.2 (P4.2) Refer to the controlled rectifier circuit shown in the figure below. With the use of suitable waveform diagrams, explain the output characteristic this rectifier. How does the output differ from the output obtained from the uncontrolled rectifiers? Task 4.3 (P4.3) Conventional fresh air supply introduced into a high-rise commercial building is normally fed via a Primary Air-handling Unit (PAU) at constant air volume. Examine the application of rectification in an PAU to reduce its energy usage. Merit Tasks Task M.1 Refer to the household distribution circuit shown in the figure below. Research and study on you own to find out and apply relevant information to enable you to calculate the branch currents I1 to I6, and then find the primary current IP. Task M.2 Suppose you are responsible for the temporary electrical installations for a circus. Find out the relevant safety regulations for this type of installations. You need to justify your source of information. Task M.3 Research on the application of power electronics in electronic ballast. Prepare and deliver a 10-minutes powerpoint presentation on your findings. You need to hand-in a hardcopy of your powerpoint after your presentation. Distinction Tasks Task D.1 Refer to Task 2.1. State how did you find information to prepare the answer? Are the sources justifiable? Review your answer and determine whether it meets the requirement of the task. Can it be improved? If no, why? If yes, how? Task D.2 Suppose you are responsible for the electrical power distribution design and installations for a new 20-storey residential building, each floor of this building will have six units. You have been assigned a three-month period to complete the job, and budgets would not be a problem. Identify the list of major tasks that need to be performed from start to finish, and provide an initial project plan that include the list of tasks. For each task , estimate the time duration, and resources required. Task D.3 Apart from the electrical power distribution network, there are other wiring networks co-exist in a modern building. Identify any three of these networks, and explore any inter-dependency they have with the power distribution network. Assignment Guideline Qualification HND in Construction and the Built Environment (Building Services Engineering) Unit number and title Unit 50 Electrical Installation for Building Services Engineering Assessor name Mike Chan / Dr. Kwan To achieve the diffident criteria that the student should fulfill the related requirement as shown as follow: Pass Criteria and Related requirement – A pass grade is achieved by meeting all the requirements in the assessment criteria for pass for each task. Merit Criteria and Related requirement –A merit grade is achieved by meeting all the criteria for M1, M2 and M3 plus all pass criteria. Distinction Criteria and Related requirement–A distinction grade is achieved by meeting all the criteria for D1, D2 and D3 plus all pass criteria and all merit criteria. Outcome (Pass outcome - extract from Outcome from course document) Possible Evidence (Given by Lecturer to guide students how to meet the criteria of outcome & this evidence will be used for assessment of the assignment) Pass Criteria P1.1 Use maximum power transfer theorem and Thevenin's and Norton's models to solve practical problems Apply Thevenin's or Norton's model to solve maximum power transfer problem. P1.2 Calculate the parameters of AC equivalent circuits using transformation theorems Apply delta / star transformation to an impedance network. P1.3 Apply circuit theory techniques to solve AC circuit problems Apply circuit theory techniques to determine voltage and current for components in an AC circuit. P1.4 Analyse the application and benefits of power factor control Describe what power factor control is and why it is required. P1.5 Apply complex quantities techniques to solve complex power and AC circuit problems Determine complex power for the components in an AC circuit. P2.1 Evaluate the appropriateness of designs in relation to environmental, access and health, safety and welfare issues Able to evaluate the appropriateness of a given electrical design in the context of environmental, access and health, safety and welfare issues by referring to current Standards. P2.2 Analyse how design constraints for a given building affect the choice of electrical distribution For a given scenario, provide an analysis to address how design constraints for this building affect the choice of electrical distribution. P2.3 Apply 'designer's discretion' when producing electrical designs for buildings Able to exercise 'designer's discretion' for a given electrical design scenario. P2.4 Evaluate the appropriateness of electrical designs in terms of complying with current standards and legislation Evaluate the appropriateness of a given electrical in terms of complying with BS 7671 IEE Wiring Regulations. P2.5 Determine optimum cable sizes for groups of cables with different cross-sectional areas and load characteristics Determine the optimum cable size for a given electrical load and installation methods following BS7671 guidelines. P3.1 Examine DC series and shunt motor applications Able to compare the torque speed characteristics of DC series and shunt motor, and suggest the applications suitable for each type. P3.2 Explain how to control the speed of DC series motors using thyristor control Able to explain the DC series motor speed control mechanism using solid state control rectifiers. P3.3 Calculate the theoretical ratings of motors for a given duty Calculate the theoretical rating of a motor for a given duty cycle. P3.4 Explain starting methods and speed control for AC motors Explain any two starting methods for three phase induction motors, and describe how to accomplish speed control in three phase induction motors. P3.5 Evaluate the suitability of AC motors for building services applications Evaluate the suitability of AC motors for building services applications in terms of energy efficiency. P4.1 Describe the operation of half-wave and full-wave rectification systems Using suitable circuit and waveform diagrams to describe the operation of a diode half-wave, and then a full-wave rectifier. P4.2 Explain the effect of using controlled rectifiers in AC circuits Using waveform diagrams, explain the output characteristic of a controlled rectifier P4.3 Examine the application of rectification in the control of electrical plant and equipment Examine the application of rectification in a Primary Air Unit (PAU) to reduce its energy usage. Outcome Possible Evidence Merit Criteria M1 Identify and apply strategies to find appropriate solutions: an effective approach to research and study has been applied Through research and study, find out how to determine the branch current of a given household distribution circuit. M2 Select/design and apply appropriate methods/techniques: the selection of methods and techniques/sources has been justified. Find out the relevant safety regulations for a temporary electrical installations , and justify the information source. M3 Present and communicate appropriate findings: appropriate structure and approach has been used Research, study, and then present a power electronic application topic with a powerpoint file. Distinction Criteria D1 Use critical reflection to evaluate own work and justify valid conclusions: For a given piece of student work, the student conduct a critical reflection by answering the following questions: How did you find information to prepare the answer? Are the sources justifiable? Does the work meet the requirement of the task? Can it be improved? If no, why? If yes, how? D2 Take responsibility for managing and organizing activities: Identify the list of major tasks that need to be performed, and provide an initial project plan for electrical power distribution design and installations for a new 20-storey residential building. D3.Demonstrate convergent/lateral/creative thinking: Identify any three wiring networks that coexists with the power distribution network inside a modern building, and explore any inter-dependency they have with the power distribution network.