Download Winter 2009 Exams for ELEC6017 in Cork Institute of Technology and more Exams Electrical Engineering in PDF only on Docsity! CORK INSTITUTE OF TECHNOLOGY INSTITIÚID TEICNEOLAÍOCHTA CHORCAÍ Semester 1 Examinations 2009/10 Module Title: Electrical Planning Module Code: ELEC6017 School: Electrical and Electronic Engineering Programme Title: Bachelor of Engineering in Electrical Engineering – Stage 2 Programme Code: EELEC_7_Y2 External Examiner(s): Mr. Gerard Beecher, Dr. Maeve Duffy Internal Examiner(s): Mr. Joe Buckley Instructions: Answer THREE questions. All questions carry equal marks. In marking scripts, the Examiner will take account of clarity of expression and communication skills. Duration: 2 Hours Sitting: Winter 2009 Requirements for this examination: Note to Candidates: Please check the Programme Title and the Module Title to ensure that you have received the correct examination paper. If in doubt please contact an Invigilator. Q1. As consultant electrical engineering technician, your job is to plan the layout of a main distribution and metering system for a new shopping centre. The board incorporates both the ESB metering and the main distribution switchgear for the complex. The complex houses: • 3 shops each with a load of 50 A, 400V, 3-phase, 50Hz • 1 shop with a load of 100A, 400V, 3-phase, 50Hz • 1 main tenant with a load of 250A, 400V, 3-phase, 50Hz The board is located within the complex and there is one ESB incoming supply. Each of the shops is individually metered using centralised metering. The distribution board is fed from a 630 kVA transformer with 4.75% impedance. A sub-distribution board located in each tenant’s premises is fed from the distribution board. (a) Draw a line diagram of the main distribution/metering board showing; (i) The current ratings and short circuit ratings for all protection devices (ii) The location of all meters. State whether whole current or current transformer metering (C/T) metering will be used. (17 marks) (b) Indicate the IP rating of the switchboard. (3 marks) Q2.(a) Explain what is meant by the following types of emergency luminaire: (i) non-maintained emergency luminaire (ii) maintained emergency luminaire (iii) sustained (combined) emergency luminaire (6 marks) (b) Emergency lighting is provided for use when the general lighting system fails and must be powered from a source other than the source supplying the general lighting. Explain how this can be achieved. (6 marks) (c) A room measuring 8m x 8m x 3m high is to be provided with emergency lighting to give a uniform illuminance on the floor. Calculate the illuminance based on the following data: (i) end of duration factor = 0.85 (ii) utilisation factor at zero reflection = 0.48 (iii) emergency lighting design lumens = 180 lumens (iv) service correction factor = 0.85 (v) number of luminaires = 2 (8 marks)
