Vibration effect of Generators

[TonyTS]

Hi, I am training to be a Building services engineer. I have come across a problem where I have to calculate the vibration from the generator and the transformer to the striation of the building.. how should I do it?

 

[Baluncore]

Maybe you mean "structure" of the building rather than "striation" of the building.
The resonant frequency of parts of the building may be sympathetic with the mechanical equipment vibration.
The equipment should be based on vibration isolating mounts.

 

[HowlerMonkey]

1800 rpms?

 

[Baluncore]

Induction motors run at (synchronous – slip) speeds determined by load. They are usually specified with about 5% slip. Unbalance vibration from the motor can be expected in a band +/–5% of the motor design speed. That will be 0.95 * supply_frequency / poles, where the number of poles is usually 2 or 4 but can also be 6 or 8.

While the vibration from motors is at motor RPM frequency, where the driven load is coupled through V-belts, load imbalance vibration will be centred on frequencies determined by the ratio of pulley diameters.

Magnetostriction in transformers will generate a buzz at twice the fundamental frequency. For 50Hz supplies that will be 100Hz, while for 60Hz supplies it will be 120Hz.