A slip ring is an electromechanical device that allows the transmission of power and electrical signals from a stationary to a rotating structure. A slip ring can be used in any electromechanical system that requires rotation while transmitting power or signals. It can improve mechanical performance, simplify system operation and eliminate damage-prone wires dangling from movable joints.

Also called rotary electrical interfaces, rotating electrical connectors, collectors, swivels, or electrical rotary joints, these rings are commonly found in slip ring motors, electrical generators for alternating current (AC) systems and alternators and in packaging machinery, cable reels, and wind turbines. They can be used on any rotating object to transfer power, control circuits, or analog or digital signals including data such as those found on aerodrome beacons, rotating tanks, power shovels, radio telescopes, telemetry systems, heliostats or ferris wheels.

A slip ring (in electrical engineering terms) is a method of making an electrical connection through a rotating assembly. Formally, it is an electric transmission device that allows energy flow between two electrical rotating parts, such as in a motor.