| Summary: | During vibration tests of structurally complex equipment on electrodynamic shakers, the measured vibrations on the shaker table, test fixtures and various places of the tested product may differ. One of the reasons is the deformable shaker table, the stiffness of which can significantly affect the results of vibration tests. The electronic equipment being tested, as a rule, does not have an axisymmetric shape and therefore, during testing, it is very difficult to align the center of gravity of the product and the vibrating table or equipment with the axis passing through the center of the shaker table. The paper theoretically shows that the shaker table can be considered a rigid body only if there is no displacement of the weight of the tested product from the center of the table, as well as at excitation frequencies significantly lower than the critical frequency of the table. For theoretical analysis, the disc-shaped shaker table is presented in the form of a thin plate. Vibrography of the vibrating platform experimentally confirmed the effect of increasing vibrations when moving away from the center of the shaker table. If during vibration tests it is not possible to place the electronic unit coaxially with the center of the vibrating table, it is necessary to monitor the value of vibrations at different points of the tested product, for example, at the points farthest from the center.
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