When a power electronics engineer is looking to select the best winding wire for their application, be it an enameled magnet wire, a triple insulated wire (TIW), or an insulated Litz Wire, the question that we get asked quite often is “What is the best insulation for my application?”.   To some, this seems like it should be a simple and straight forward question.  As with most engineering challenges we face, the initial response is “It depends.”  While there are a myriad of insulation materials and processes including enamel coatings, textile serves or braided layers, and tape wraps, this article is going to focus on providing information on how to select an extruded insulation for various applications.

As Rubadue Wire began the process of creating the first extruded triple insulated winding wire, we recognized that one of the effects of the then pending energy efficiency standards and the reality of making power transformers and wound magnetic components smaller, was that there was going to be the need for winding wire products that could withstand the higher thermal stresses resulting from the higher power densities and changes in manufacturing processes. It was through this process that Rubadue Wire focused on refining insulation materials that would provide excellent thermal resistance along with exceptional dielectric strength in the thinnest possible layers that would not only meet but exceed the requirements of global safety standards.

Insulation Materials & Descriptions:

Today, Rubadue Wire offers four distinct insulation types to meet the rigorous demands of our customers’ applications.  Compatible with high-speed winding equipment and high temperature reflow manufacturing processes, our multi-layer winding wires provide our customers with customizable options. This allows design engineers to continue to create innovative solutions in the ever-evolving power electronics marketplace.

  • TCA – An economical design option when the need to move from a lower thermal class to a 155°C rated wire is required for improved product performance, end-use safety certification or due to changes in a manufacturing process or technology.  With voltage ratings up to 1,500 Vpk, TCA insulated wires are ideal for use in Consumer Electronics, Medical Devices, Solar Inverters, as well many Industrial Power Conversion and Test Equipment applications.
  • ETFE – A durable, abrasion resistant material that offers excellent dielectric strength and is ideal for when heat and chemical resistance are required.  With approvals allowing for insulation thicknesses as thin as .0010” (0,025mm) per layer, ETFE is the ideal choice for when very tight tolerances in the winding window require the smallest possible diameter wires to continue to operate without sacrificing performance.  ETFE insulated wires are found in many Electric & Hybrid Vehicle charging applications as well as Solar, Medical and Consumer Electronics.
  • FEP – a more flexible insulation approved for use up to 155°C, FEP offers improved heat resistance allowing for short-term exposure up to 200°C.  FEP insulation is ideal for use as an insulation over Litz Wire conductors for use in high frequency applications.
  • PFA – approved for use up to 180°C, PFA offers excellent heat and chemical resistance along with superior dielectric strength. Designed to withstand temperatures up to 260°C, PFA is ideal for use in high temperature reflow manufacturing environments and can be found in many critical power, industrial control, and test equipment applications.

All our insulation materials are recognized by both UL and VDE for use in a variety of industries and have been approved by UL for use in Rubadue Wire’s 155°C (Class F) Electrical Insulation Systems designated RXT-2 and TCA in accordance with UL 1446 and IEC 60085.  Additionally, there are many other systems approved by UL that are available for adoption which contain many of the winding wires produced by Rubadue Wire.

As you begin to determine your requirements for the level of isolation, the thermal class, and the operating voltage needed for your project and would like more information, please contact the Rubadue Wire Sales Team to discuss your needs.