A single-phase transformer has its maximum efficiency at 60 percent of full load.
At full load copper loss will be
A. equal to core loss.
B. less than core loss.
C. more than core loss.
D. zero.
Answer: C
Share your understanding of this question with the correct explanation.
In a single-phase transformer, the efficiency is given by the ratio of output power (load power) to the sum of input power (primary power) and losses. The losses in a transformer consist of copper losses and core losses.
Since the maximum efficiency occurs at 60 percent of full load, we can assume that at full load, the efficiency will be slightly lower. This implies that the losses at full load will be higher compared to the losses at maximum efficiency.
Among the losses, copper losses are caused by the resistance of the transformer windings and increase with the square of the load current. Core losses, also known as iron losses, are caused by hysteresis and eddy currents in the transformer core and are relatively constant regardless of the load.
Therefore, at full load, the copper losses will be more than the core losses. Hence, option C, “more than core loss,” is the correct answer.