Also referred to as I2R loss, this is the power dissipated in the coil when current is flowing. As the second term implies, the power dissipated is the load current squared times the DC resistance of the coil. This is valid for low frequencies, such as 50 Hz (European commercial power) and 60 Hz (American commercial power) but gets more complicated as the frequency goes up. The overall effect is still copper loss but there are other effects at higher frequencies. See proximity effect and skin effect.

The energy wasted as heat in the copper (or aluminum) windings, as copper/aluminum is not a perfect conductor of electricity.

The power loss (PR) or heat generated by current (I) flowing in a winding with resistance (R)

Power lost in transformers, generators, connecting wires and other parts of a circuit due to current flow through the resistance of copper conductors.

Power lost in an inductorâ€(tm)s windings due to resistance of the magnet wire impeding the flow of electric current, the current can be AC, DC or a combination of both. The loss changes electric energy into heat energy.

The power lost because of the resistance of the conductors. In transformers the power lost because of current flow (I) through the resistance (R) of the windings.

Copper loss occurs in the form of heat which is produced by the electrical currents in the conductors of transformer windings. Called I squared R losses, they increase as the amount of current through the windings and the electrical resistance of the conductors increase. These losses are minimized by employing large diameter conductors to reduce the resistance per unit length of the wires.