Answer Happy

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. (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 W, Input Current = 6.0 A Calculate R, X, R and X m² eq 0 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 ii) The regulation at this load iii) The efficiency at this load (d) The company electrician wants to utilize three of these single-phase dry type transformers for a three-phase commercial installation. Sketch how these transformers would be connected to achieve a delta-wye three phase transformer.