For use with AC squirrel cage or wound rotor induction motors in open or closed loop systems. These drives may be used for crane travel and hoist motions. May be used with AC solenoid or rectifier operated brakes, and with power and control circuit limit switches. Controls are rated for 50°C as standard. The Class 6417/6418 AC drive system is suitable for new installations or for retrofit of existing electromechanical control.