how to calculate the power rating of a transformer?

To calculate the power rating of a transformer, you need to consider its primary and secondary 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 P = V_primary � I_primary or P = V_secondary � I_secondary. For three-phase transformers, the formula is P = ?3 � V � I. Ensure that the voltage and current are in the same units for accurate calculations.