IST Power is incorporates three established names within the transformer industry:

  • International Transformers
  • Stewart Transformers
  • Transtech Transformers

Over the 2 locations, we have the ability to manufacture a wide range of transformers and wound components up to 6MVA, 66kV and 250kV for Test Transformers.

We supply the following types of transformers/reactors:

  • Liquid immersed transformers or reactors in oil, Midel, water or approved environmental alternatives.
  • Natural air cooled
  • Force air cooled
  • Cast or encapsulated resin


  • Various Cranes up to 20 Tonne lift capacity
  • 3D Autodesk Inventor and thermal modelling technology
  • Various winding machines and jigs to support multiple winding configurations i.e. strip, foil, ctc and hollow section in copper or aluminium
  • Ovens to support processing of coils up to 66kV and 250kV for test transformers
  • Automated winding machines for volume production
  • Vacuum pressure impregnation facilities including enveloping tanks
  • Casting and encapsulating ovens
  • Fabrication facility for manufacturing accumulators, stainless steel manifolds, sheetmetal clamps, steel enclosures and flameproof fabricated tanks
  • Paint facility covering all preparation, intermediate to final paint processes of small components to complete tanks and enclosures
  • High Voltage testing up to 150kV AC and 200kV DC with frequencies up to 500Hz