Process and apparatus for diagnosis of machine

The invention relates to a method and apparatus for diagnosis of machine (10) for the production of products, such as cigarettes (12) or cigarette packs (11), wherein the products are inspected for defects and a defective product indicative signal is generated. The invention addresses the problem of improving the diagnosis. DOLLAR A To solve this problem, the inventive method is characterized in that the fault-indicating signal (46) for possible periodicity of defective products (11, 12) are evaluated and a possible periodicity is determined. To this end the device according to the invention on a correspondingly designed control means (27a).