The invention relates to a method for controlling machines (20), especially decanters and separators, according to which operational states (30 36), such as current consumption, temperature, conveying speeds, etc. are detected on the machine and are compiled and stored in a computer (5). The data is subsequently transmitted to a second computer (10) in order to be able to analyze this data. The analysis involves the comparison of the actual state with a set state in order to, in the case of a deviation located outside of the tolerance zone, generate an error message that is then automatically output by the second computer (10) to a peripheral unit and/or to additional computers. To this end, an adaptive multi-layer mathematical model of the machine and of the process is generated. According to the invention, an information system for operating a machine (20) is also provided with which the control method can be executed. Potential error states on the machine can be identified early by the automatic detection and relaying of the operational states so that they can be intervened with before damage occurs.