Core
- Cold-rolled core-orientated steel sheet in "step-lap" layering reduces no-load losses and noise.
- Binding and a two-part coating keep the core together, protect against corrosion and prevent the generation of noise.

LV-winding
- A temperature process bonds the prepreg with the strip into a compact cylinder.
- As the current distributes freely across the full-height conductor, the forces unleashed by short circuits are reduced.

HV-winding
- Multi-layer winding with epoxy/glass fibre insulation without void free cast in a mould.
- The very low-viscosity epoxy filler impregnates the glass fibre mats via vacuum and capillary action.
- Ducts improve the cooling procedure. This reduces the size, in particular the height.
- Even extreme and rapid changes in temperature do not destroy the winding. This is due to the balance between strength and elasticity of the epoxy/glass fibre composite.
- Routine testing verifies the partial discharge level < 10 pc on the coils and on the transformer.
- Ageing tests are effected at increased temperatures and extreme climatic conditions and confirm a prolonged service life and freedom from partial discharge.