Crane resistors are resistors or resistor units used in crane drives. In general, this term covers the rotor resistors for drive, lifting, trolley and closing gears. For these applications, standard switchgears and standardized stepping were developed that cover the most common operating conditions. Both the robust cast iron resistors and steel grid resistors are suited for such applications while wire-wound resistors are found less often. With a view to the growing size of frequency converters and their elegant and low-loss control options, use of the slip-ring motor is on the decline, and with it that of the rotor resistor. Instead, braking resistors are taking over in applications where energy recovery is not economical or not feasible.