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Q2. As an engineer for a private contracting company, you are required to test some dry-type transformers to ensure they are functional. The nameplates indicate that all the transformers are 1.2 kVA, 120/480 V single phase dry type. (a) With the aid of a suitable diagram, outline the tests you would conduct to determine the equivalent circuit parameters of the single-phase transformers. (6 marks) (b) The No-Load and Short Circuit tests were conducted on a transformer and the following results were obtained. No Load Test: Input Voltage = 120 V, Input Power = 60 W, Input Current = 0.8 A Short Circuit Test (high voltage side short circuited): Input Voltage = 10 V, Input Power = 30 W, Input Current = 6.0 A Calculate R, X, R and X (6 marks) m eq eq (c) You are expected to predict the transformers' performance under loading conditions for a particular installation. According to the load detail, each transformer will be loaded by 80% of its rated value at 0.8 power factor lag. If the input voltage on the high voltage side is maintained at 480 V, calculate: i) The output voltage on the secondary side (4 marks) ii) The regulation at this load (2 marks) iii) The efficiency at this load (4 marks)