This invention relates to a system for automatically self-adjusting the height, length and direction of an electrical power cable connecting a movable machine, such as a crane, to a fixed electrical power supply. One end of the cable is wrapped around a reel which is arranged within a housing that is freely rotatable about a vertical axis. That end is connected to an electrical power source. The opposite end of the cable is connected to a machine which is moveable towards and away from, and around, the reel. A motor rotates the reel for winding up, and applying a tension upon, the cable so that the center portion of the cable, which extends between the reel and machine, is held relatively taut and generally horizontal. The central portion of the cable extends through a vertical slot in the housing so that its height, length and direction of extension towards the machine are automatically adjusted in response to the position of the moveable machine relative to the reel.