Siemens' Sinumerik 840D sl CNC provides energy-efficiency options for turning centers. Equipped with a Sinumerik Operate user interface and Sinamic S120 drives, the control is capable of shutting down processes when they are not in use. For example, the control shuts down the fans on the spindles automatically when they are not required, and other services such as lubricant supply are deactivated during machine standstill times. These functions are handled via special screen forms on the control using the “run MyScreens” function. The drives include automatic power factor correction and regenerative feedback of the energy generated in braking operations for additional energy savings.