IsoTek Innovation

PoSeCo: Alternative to metallized core shielding

PoSeCo, abbreviation for Polyglas® Semi Conductor, is a conductive Polyglas® tape that revolutionizes the way in which transformer cores are shielded and protected. It is made of Polyglas® and was developed to replace both the metallized core shielding and the mechanical fixing straps around the core columns. PoSeCo offers you a number of advantages over conventional methods, including:

  • Reduced material consumption, shorter production time and lower costs.
  • Improved quality and reliability with minimized risk of errors.
  • Simplified and standardized processes.


Quality advantages

  • Risk minimization by eliminating work steps in the production and assembly of metallized core shields.
  • Hardened, continuous Polyglas® cylinder prevents sheet displacement due to acceleration during transport.
  • Short-circuit-proof support without additional strips in the corners of the core steps between core and winding. 

Technical advantages

  • Compactly pressed and bandaged core limbs.
  • Hardened cylinder also serves as shielding and mechanical support for the winding.
  • By eliminating the strips in the corner of the core steps: better cooling of the core laminations due to barrier-free oil flow between the cylinder and core steps.


Do you have questions about our product?

Our staff will be happy to help you.

Patrick Sitte

Application Manager
+49 6298 93753-53

Profitability analysis

(Example: Dimensions: 3-phase core / 100 MVA, limb diameter: 720 mm, window height: 1,800 mm)

By using PoSeCo tape instead of a conventional metallized core shield, it is possible to reduce the distance between winding and core by approx. 5 mm on one side. This leads to a reduction in the diameter of the windings by 10 mm. As a result, the core width can be reduced by 10 mm and the core length by 30 mm.

This has an impact on the weight of the tank, the oil volume, the insulation content and the copper weight, as well as on the core sheets and the press beam. For a 100 MVA transformer, the total cost of these materials can be estimated at -2% due to the change in dimensions and can be considered as savings.

In addition, the manufacturing costs for the metallized shielding as well as the production and application of the core bandages with a core stacking table occupancy time of at least one shift must be taken into consideration.

The perfect solution for shielding and protecting transformer cores

PoSeCo tape is a semi-conductive Polyglas® tape developed for electrical shielding and mechanical stabilization of transformer cores. It has excellent mechanical properties and is designed for thermal class F (155°C). PoSeCo tape is made of parallel glass yarns, pre-impregnated with a thermosetting polyesterimide resin. The product is supplied in B-stage (semi-cured) to be soft and flexible when applied. After curing, it forms a homogeneous, hard cylinder.

PoSeCo tape is a revolutionary product that changes the way transformer cores are shielded and protected. It offers a number of advantages over conventional methods, including lower material consumption and cost, improved quality and reliability, and a simplified process.

PoSeCo tape is the perfect solution for shielding and protecting transformer cores. Contact us today to find out more.