Transformer Vibration - Dry type

[varri79]

Dear Gentlemen,
What are the reasons for vibration of dry type transformer enclosure? How can we find the cause?
Specs.:
Rating: 2000kVA, 11/0.414kV,50Hz dry type transformer
Your answer will be highly appreciated

 

[edison123]

Loose Core laminations

 

[RonShap]

Try this site

http://www.federalpacific.com/university/transnoise/transnoise.html

 

[dpc]

All transformers vibrate due to magnetostriction in the core. It is more noticeable in dry type xfmrs because of the absence of oil to damp out the vibrations. We typically connect to small dry-type units using flexible conduit for this reason. You can also buy rubber feet for the transformer to sit on if noise is an issue.

 

[varri79]

More vibration and sound is coming from the particular transformer but not other similar type transformers. Core bolts are tights and bed bolts are fixed with rubber pads. It is a stand-by transformer and usally operating without load.

 

[GamezBeCJ]

Also you want to be sure you are not overexciting the transformer.

 

[Dumbo2929]

Transformers with little or no load see higher voltages, which generate more flux in the core, causing more vibrations in the laminations. New transformers can be specified to meet lower noise requirements. On existing transformer installations, the use of flexible, non-metallic conduit and vibration isolators can help reduce noise. The only other option is to reduce the incoming voltage through use of an upstream tap changer, deenergizing capacitors, etc. Replacing the transformer with an oil-filled unit would work, but is very expensive.