Since 1938, Tierney Electrical Manufacturing Company has built a solid reputation as a dependable source of all copper wound, conservatively designed dry-type transformers.

Specialists in the dry-type transformer field, Tierney Electric has continued over the years to provide its customers with personalized attention to all details. We provide competent assistance with reliable price and delivery quotations on both industry standard and custom-designed transformers.

The Success of the company over the past sixty years can be attributed to basically four things:

  1. Our continued high quality and extremely dependable copper wound products.
  2. Our good customer relationships that we have developed over the years.
  3. Our dedicated employees with many years of experience in the manufacture of dry-type air-cooled electrical transformers.
  4. Our quick and reliable delivery.

With our manufacturing plant located in Seattle, Washington, Tierney Electrical Mfg. Company offers very efficient operating air-cooled transformers, sized 50 VA through 3000 KVA.

We look forward to forming relationships with new customers, as well as continuing to support our regular base customers as well. We generally ship a transformer on the date we quoted. Our reputation is known for this, as is the quality of our product.

Statement of Policy

It is the firm belief and policy of Tierney Electrical Mfg. Company that all transformers must meet all requirements of a customers specification 100%. We do not believe that any single manufacturer's standard product, however good it may be, can possibly provide an ideal solution to all transformer applications. Variations in voltage ratios, KVA ratings, size limitations, taps, frequency, etc., provide many application problems which can be solved only by custom-design and manufacture.

To maintain our policy of 100% fulfillment of specifications, we will, when necessary, alter our standard designs and make the required revisions to our normal manufacturing processes to ensure that the user obtains a high-quality transformer exactly meeting specifications.

Our standard transformers are designed to operate 3 to 5 dB below ANSI standards which result in a very quiet operating transformer.

For those applications requiring a transformer having a sound level much lower than ANSI standards, we will design and construct a transformer guaranteed to meet the specified sound levels. These units are individually sound-level tested using ANSI Standard test procedures, and copies of certified test reports are furnished to the specifying authority as proof of compliance.

Some of Tierney's customers Include:

  • Boeing
  • Boise Cascade
  • F.A.A.
  • Fort James
  • Georgia Pacific
  • Microsoft
  • Raytheon
  • Simpson Timber
  • Weyerhauser
  • U.S. Dept. of Defense
  • U.S. Postal Service