Q2. As an engineer for a private contracting company, you are required to test some dry-type transformers to ensure they

[answerhappygod]

Q2 As An Engineer For A Private Contracting Company You Are Required To Test Some Dry Type Transformers To Ensure They 1 (59.38 KiB) Viewed 33 times

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) (4 marks) 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. (3 marks) (Total 25 markal