A door actuating system has a fractional horsepower motor mounted on the door adjacent its free edge, driving a clutch connected to a duplex capstan pulley that is wrapped by two tensioned flexible static lines, for opening/closing movement ‘along the line’. The motor also drives a gear that engages a rack projecting from the door frame, to displace the door relative to its frame. Rotation of the gear is read by a rotary encoder, which feeds a microprocessor, to continuously monitor the location, speed and direction of motion of the door, for both the ‘on’ and the ‘off’ condition of the electric motor. A latching clip over-rides action of the original door latch.