This document discusses single and three phase transformers and how to determine their equivalent circuit values. It covers the demagnetizing effect, voltage drops due to load current, and describes tests like the d.c. resistance test, open circuit test, and short circuit test which are used to find the equivalent circuit values for transformers. An example is also provided.

1. Single and Three Phase
Transformers
Learning Outcome 2

2. The Demagnetising Effect

3. Voltage Drops due to Load
Current

4. Determination of values for the
equivalent circuit

5. The d.c. resistance test

6. The open circuit test

7. The short circuit test

8. Example