Dry-Type Cast Coil Transformers

Continuous Performance Matters

Dynapower is pleased to offer the ULTRACAST line of cast coil transformers, designed for applications that demand high reliability and continuous performance. Developed in the United States, the ULTRACAST process locks the windings in a very strong, high dielectric, epoxy resin, thus protecting the transformer from extremely severe environments and electrical demands. These units meet rigorous operating parameters efficiently, safely, and reliably. Cast coil transformers feature a long service life, lower insurance expense, and are virtually maintenance-free, all of which reduce the cost of ownership. These transformers are also environmentally safe, which benefits the end user as many types of liquid-filled, medium voltage equipment have been made obsolete by environmental concerns and increasing insurance costs.


  • Custom electrical and mechanical designs available for Industrial and utility distribution and rectifier applications
  • 300 kVA to 10 MVA  standard range with other options available
  • 600 V to 35 kV class voltages
  • 10 to 150 kV basic impulse levels
  • 80° and 115° C temperature rise levels standard with other options available
  • All coils wound with copper conductors.
  • DuPont Nomex® UL recognized 220° C insulation system
  • Both primary and secondary windings cast in 200° C UL recognized epoxy
  • Convection cooled, forced air and direct water cooling system available
  • Mitre cut, cruciform, step lap core fabricated from M6 grade grain oriented silicon steel standard, but other grades also available
  • Numerous NEMA and specialty enclosure options available
  • Nationally recognized testing laboratory (NRTL) inspection and approval available