Q4.(a) The water utility requested a supply from the electric utility to one of their newly built pump houses. The pumps

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Q4 A The Water Utility Requested A Supply From The Electric Utility To One Of Their Newly Built Pump Houses The Pumps 1 (237.13 KiB) Viewed 35 times

Q4.(a) The water utility requested a supply from the electric utility to one of their newly built pump houses. The pumps require a 400V three phase and 230V single phase supply. The load detail submitted indicates a total load demand of 180 kVA. As a distribution engineer employed with the electric utility, you are asked to consult with the customer before the supply is connected and energized. i) With the aid of a suitable, labelled circuit diagram, explain how the different voltage levels are obtained from the 12kV distribution lines. (7 marks) ii) State the typical current limit for this application, calculate the corresponding kVA limit for the utility supply mentioned in part i) and inform the customer of the repercussions if this limit is exceeded. (7 marks) iii) What option would the utility provide the customer for metering based on the demand given in the load detail? (3 marks) iv) What metering considerations must be made if this load demand increases by 100% in the future? (2 marks) (b) You built an electric device for a design project that works on the 115V supply from a general-purpose domestic outlet. To be safe, you opt to use a fuse to protect the electrical components of the device from overvoltage in the supply or accidental faults in the circuitry. With the aid of a suitable diagram, show how the fuse would be connected to the terminals of your device and describe its construction and operation.