Auto Transformers

MSI Auto Transformer

Compared to dual wound transformers with a primary and secondary winding, an auto transformer has only one winding which acts as the primary and secondary. As a result when compared to a traditional transformer of equivalent KVA rating, an auto transformer will be smaller, lighter and cheaper. Magnetic Specialties can design and manufacture a variety of auto transformer topologies including single phase, three phase, and even two to three phase auto-wound phase changers.


  • Single Phase, Three Phase, 2-3 Phase
  • Frequency of operation includes 50, 60, and 400 Hz
  • Ratings up to 1200 KVA
  • Aluminum or Copper windings
  • Optional NEMA 1 or 3R enclosures