Iron losses of a transformer are also called __________

• A. No-load losses
• B. Load losses
• C. Copper losses
• D. Core losses

Answer: (A)

Iron losses are losses in the magnetic core due to hysteresis and eddy currents. These losses occur whenever the core is magnetized by the applied voltage, not because current is flowing in the load. When the transformer is energized but has no load on the secondary, the only losses present are these core (iron) losses. Hence they are referred to as no-load losses. Under load, additional losses appear from the windings (copper losses), but the core losses remain and are independent of loading, which is why the no-load losses term fits this concept.