Managing virtual and real machines through a provisioning system. The switch on and off time is controlled to regulate the output power and the circuit is such that on light loads the resonant circuit decouples from the track. The areas where occlusal contact occurs is displayed on the user interface in a readily perceptible manner, such as by showing the occlusal contacts in green. Inside at least one of the drive networks, its nodes or drive units are arranged in accordance with the masterslave principle and are respectively connected to one another in a ring structure through communication channels andor a communication system.