Method for evaluating a vibrational event

Method for verifying the installation of a device (50) or apparatus (1) provided with at least one accelerometer (102), said method comprising carrying out a procedure (203) to determine the natural installation frequency of said device (50) or apparatus (1) in which at least one stress is applied from the outside to the device (50) or apparatus (1) and further comprising, for each applied stress:

• acquiring the data detected by the accelerometer (102), which is mounted on the device (50) or on the apparatus (1), respectively along three axes X, Y and Z which are perpendicular to each other,
• processing at least one portion of the three signals, derived from the data thus acquired respectively along the three axes X, Y and Z, in order to bring said at least one portion into the frequency domain,
• verifying if the passage to the frequency domain has occurred correctly and, only in case of positive verification, the natural frequency is determined for said at least one portion of each of the three signals, derived from the data thus acquired respectively along the three X axes, Y and Z, which has been brought into the frequency domain,
• and on the basis of the natural frequencies thus calculated for each applied stress, the natural reference frequency associated with the installation of the device (50) or device (1).

Method for controlling the modes of operation of an accelerometer (102), which is configured to operate in at least:

• a first mode in which the data are acquired at a first sampling frequency, and
• a second mode in which the data are acquired at a second sampling frequency, which is higher than said first sampling frequency,
• the method comprising:
• acquiring the data detected by the accelerometer (102) operating in said first mode along three axes X, Y and Z which are perpendicular to each other and, when at least one data thus acquired is higher than a predefined threshold value Th9, the accelerometer (102) starts operating in said second mode,
• acquiring the data detected by the accelerometer (102) operating in said second mode along three axes X, Y and Z which are perpendicular to each other for a predefined period of time Tc,
• determining the values of frequency F and intensity I of the signals derived from the data thus acquired,
• comparing the values of frequency F and intensity I thus determined with respective threshold values Th10,
• establishing, on the basis of said comparisons, whether or not to return the accelerometer to work in said first mode.