Get ready for more efficient transformers

The National Electrical Manufacturers Association (NEMA) is upgrading its efficiency standards for distribution transformers. It says its new NEMA Premium Efficiency Transformer Program will result in super high-efficiency electrical transformers being installed in commercial buildings and industrial plants.

The old transformer standard, NEMA TP 1-2002 Guide for Determining Energy Efficiency for Distribution Transformers, was later adopted by the U.S. Dept.of Energy (DOE) as the national energy-efficiency rule for low-voltage dry-type distribution transformers. The new NEMA Premium Efficiency Transformer designation requires 30% less loss than existing DOE regulations (10 CFR 431) for low-voltage dry-type distribution transformers.

“Actual efficiencies for these new premium transformers range from 98 to more than 99%, depending on the size of the transformer,” said John Caskey NEMA industry director.

The transformers covered under the new program are typically used in commercial and industrial applications. However, some electric utilities are considering the NEMA program for their commercial and industrial energy-efficiency rebate programs.

The NEMA Premium transformers, like NEMA Premium induction motors, use greater amounts of electrical steel and copper than used in older transformers to obtain higher efficiency levels. Use of larger amounts of the more costly materials is likely to make the NEMA Premium-level transformers premium priced as well.

To date, seven manufacturers have committed to providing NEMA Premium Efficiency Transformers to the marketplace. They include Eaton Electrical, Federal Pacific, GE Energy Industrial Solutions, Hammond Power Solutions, ONYX Power, Schneider Electric, and Siemens Industry.

More information is available at the NEMA site:

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