The Drive Unit is the mechanism which pulls the cable through the system. The cable is pulled through the Drive Unit by a sprocket driven by a .75kw electric power motor and Gear Reducer.
The cable enters the left end of the Drive Unit, travels around the sprocket & is picked up by two Idler Wheels, which guide it to the outlet on the right end of the Drive Unit.
The outgoing cable travels under the incoming cable, allowing material brought into the Drive Unit to drop onto the outgoing cable and be carried out returning it to the system.
One of the two Idler Wheels is spring-loaded to act as automatic tension device, removing slack from the cable. If the slack becomes excessive, or if the tension becomes too high, a Drive Unit Safety (Roller) Switch will shut off the Drive Unit.