Tierney Electrical Manufacturing “Quietran” Transformers

What “Quietrans” Are:

 “Quietrans” are a high-quality line of dry-type transformers with consistently-low inherent sound levels. Before shipment from the factory, each transformer in the “Quietran” line is individually tested using ANSI Standard test procedures, and is guaranteed to have a maximum inherent sound level of 35 db. This ANSI guaranteed maximum figure ranges from 12% to 36% BELOW the current ANSI Standard sound levels. The transformer is built with a larger core and coil to reduce the magnetic core density. This proportional reduction gives a corresponding reduction in sound levels. The air gap is also manufactured to be as small as possible. Most standard transformer noise is caused by 3 factors, loose laminations in the core, burrs in the core steel, and magnetic core density. Careful manufacturing processes can control all three factors which are the major cause of tranformer noise. As an additional benefit the transformer is dipped a second time in varnish to provide a high quality low noise design. Each design is individually tested and certified to be below the 35 db sound level. Test reports are available on request.

Did You Know?

For every 3 db increase, the apparent sound doubles. Example: A 45 db transformer is approximately twice as noisy to the human ear as a 42 db transformer.

 Where to Use “Quietrans:

 In hospitals, schools, quiet offices, or in any other low-ambient sound-level locations where the inherent “hum” of transformers would be annoying to personnel.

"General Information about “Quietrans:”

Below are tabulated various dy-type transformer sound-level standards for convenient comparison:

 

Transformer Rating	ANSI C89 Std.	Present Industry Std.
0-9 KVA	40db	40db
10-50 KVA	45db	45db
51-150 KVA	50db	50db
151-300 KVA	55db	55db

 What “Quietrans” Can Do For You:

 Because of their extremely-low sound-level performance, “Quietrans” enable you to place dry-type trans­formers nearer to the center of load, reducing voltage drop, and virtually eliminate the need for “hiding” noisy transformers in janitor’s closets, storage rooms, etc.

How to Specify Tierney “Quietrans:”

Dry-type transformers rated 300 KVA and below shall be Tierney Electrical Mfg. Co. “Quietran” series, with a guaranteed maximum sound-level of 35 db. Certified copies of factory sound-level test reports covering each transformer intended for use on this project shall be provided to the Architect or Engineer.

 

Add Suffix “QT” to catalog number for “Quietran” feature.