What are Energy Efficient (TP1) Transformers?

TP1 was often used to generically refer to the minimim efficiency levels that were originally require in Canada in 2005 and in the U.S. in 2006 for low voltage ventilated transformers. Specifically, the TP1 specification covers energy efficiency in transformers based on the NEMA Standards Publication, TP-1-1996, “Guide for Determining Energy Efficiency for Distribution Transformers”. The TP1’s recomendations did consider the total owning cost of ownership unique for industrial or commercial installations. TP1 is measured per TP2 and displayed on the nameplate per TP3.

The TP1 specifcations have now been replaced by higher efficiency specifications:

  • U.S.A.: DOE 2016 efficiency levels (January 1st, 2016)
  • Canada: NRCan 2019 efficiency levels (May 1st, 2019)