Fault diagnosis device, fault diagnosis method and machine to which fault diagnosis device is applied

A fault diagnosis device for a machine in operation, the device comprising:

• an abnormality degree analysis unit that calculates the abnormality degree of each component configuring the machine by comparing output data of the machine with a threshold value;
• a fault tree automatic generation unit that holds a fault tree of each component in which the fault of each component and the fault of a sensor in each component are associated with each other and generates the fault tree of the entire machine by coupling the fault trees of the components on the basis of a correlation between the output data of each component;
• a fault analysis unit that analyzes the fault of the machine on the basis of the abnormality degree and information of the fault tree of the entire machine;
• a display unit that displays information analyzed by the fault analysis unit and issues an alarm;
• and
• wherein in the fault tree of the component, the fault of the sensor is described using a phenomenon that is caused by the fault, and for a fault mode that is high in the abnormality degree analyzed by the abnormality degree analysis unit, the fault analysis unit counts the number of phenomena with the same description in the fault tree of the entire machine and calculates the fault degree on the basis of the number.