Wire-wound resistor

This refers to the resistance of windings wrapped around the core of transformers or choke coils. Copper wire, which has low electrical resistance, is mainly used for windings. When electric current flows through the winding, losses occur due to its resistance, which are called copper losses. Copper losses are also known as load losses and increase in proportion to the square of the current. Therefore, in order to reduce the losses in transformers or choke coils, it is desirable for the winding resistance to be as low as possible.