Dongan offers single phase ventilated transformers from .50kVA to 5kVA and encapsulated transformers from .250kVA through 25kVA. Our enclosures are NEMA 3R as standard with only some exceptions at the smallest kVA which are indicated in the catalog. These transformers can be wall mounted or floor mounted cabinet style depending upon the kVA rating. These are UL and CUL listed and are copper wound through 25kVA. In addition, we also offer TP-1 Energy Efficient Transformers starting at 15kVA and larger as required by the D.O.E. These transformers meet the minimum energy efficiency requirements as set forth by the Department of Energy in EPACT. Dongan's TP-1 transformers begin with the prefix 41 for aluminum wound and 42 for copper wound transformers. These are competitively priced against our competition.