VDI 4550 Blatt 3:2018-08

The assessment of mechanical vibrations of a machine is based primarily on a series of parameters. These characteristic values are formed or calculated by means of characteristic functions from vibration measurements. Exceeding the specified limit values signals a warning or alarm condition. In order to simultaneously monitor several characteristic values for a machine or plant, several such characteristic values are usually monitored independently of each other in parallel. Level increases or limit value exceedances indicate an error in the assigned machine element or - in the case of broadband monitoring - a deterioration of the overall dynamic condition. However, a single overall characteristic value is also valuable for assessing a good machine. If the status of the plant is displayed as good, for example, it can be concluded immediately whether the plant is suitable for an upcoming major project or whether it should be overhauled beforehand. In multivariate statistics, multivariate methods (including multivariate analysis methods) are used for the simultaneous investigation of several statistical variables or random variables. Such procedures are described in this standard.