Noise/vibration reduction device for transformers

A noise/vibration reduction device used in a transformer including a tank having an internal space and a tank side wall defining an exterior of the tank, comprising:

• a plurality of through hole plates installed on the tank side wall, each of the plurality of through hole plates having at least one through hole disposed therein;
• and a plurality of support members positioned between adjacent ones of the plurality of through hole plates and between one of the plurality of through hole plates and the tank side wall to define a plurality of spaces including a first space, a second space and a third space between the adjacent ones of the plurality of through hole plates and between the one of the plurality of through hole plates and the tank side wall, wherein each of the plurality of through hole plates has different specifications of the through holes disposed therein to reduce noises having different frequencies, wherein the plurality of through hole plates include a first through hole plate having at least one first through hole disposed therein, a second through hole plate having at least one second through hole disposed therein, and a third through hole plate having at least one third through hole disposed therein, and wherein a plurality of first support members are positioned between the first through hole plate and the second through hole plate to define the first space, a plurality of second support members are positioned between the second through hole plate and the third through hole plate to define the second space, and a plurality of third support members are positioned between the third through hole plate and the tank side wall to define the third space.