how to calculate power rating of a transformer?

To calculate the power rating of a transformer, you need to consider its voltage and current ratings. The power rating (in watts) can be determined using the formula: Power (P) = Voltage (V) � Current (I). For single-phase transformers, use the formula P = V � I, while for three-phase transformers, use P = ?3 � V � I. Ensure that the voltage and current values are in the same units for accurate results.