Abstract: An apparatus for the motorized control of theatrical sets connected to manual lift units each comprising upper and lower pulleys upon which a line runs to raise and lower a counterweight operatively connected to a set on the stage by a plurality of lift lines is comprised of a series of upper and lower sheaves for support of an independent control line connected to the counterweight. The sheaves are positioned as to not interfere with the manually-operated lines. A drive drum and motor drive unit is associated with each upper and lower sheave, and runs the control line. The drive drums and motor drive units are arranged in a spaced array such that the drive units may be connected and discounted to the drive drums as necessary and required by a particular set configuration, thus eliminating the need for all drums of the array to be coupled to drive units at all times.