How to Choose the Ideal Electrical Insulation Tape

Roughly comparable to a seal of approval on packaging in a shopping trolley, specifications play a key role in the electro-mechanical and other specification-driven markets. They help engineers and users quickly identify products that meet defined criteria based on standards like technical or safety requirements and save time and ensure reliable performance.

In the electro-mechanical market, UL (Underwriters Laboratories) is the leading safety certification and can be divided into UL listed and UL recognized. While UL listed refers to the entire standalone item, UL recognized is used for components of products, not the finished product itself.

Whether you work on new application solutions or are replacing currently used materials, relying on specified tapes is a smart and safe choice.

Single-sided tapes where the backside is adhesive-free are usually used to increase part protection in electro-mechanical applications. They allow for higher current, higher energy density or the use of special oils and varnishes. Additionally, they reduce wear and tear, add puncture resistance and reduce maintenance needs, prolonging the lifetime of parts.

Double-sided tapes are used to bond or attach components to different surfaces. Transfer tapes consist of only an adhesive layer (unsupported) while many double-sided tapes have a carrier between the adhesive layers that can add different functionalities like additional strength, dampening, sealing, fire protection or conformability.

Reinforced tapes are mostly designed with special net constructions, glass cloth or glass filaments to combine high tensile strength with good adhesion, high temperature resistance and good conformability. These tapes are the right choice for the insulation and outer wrapping of e-motors and dry or oil-filled transformers.

Finding the right backing material from a multitude of options can be difficult. The most expensive and highest performing ones might not be the best choice for all applications. To avoid wrong choices, under or overperforming tapes, it is essential to know the exact application needs.

Film Insulation Tapes offer good adhesion to various substrates, good conformability, thermal resistance and insulation of electronic components. They are ideal for wrapping and interlayer insulation of coils for e-motors and transformers or masking applications.

PET Film Insulation Tapes are an economical solution, whereas tapes based on PEN and Polyimide offer increased thermal and dielectric resistance for non-stick applications. Non-woven Polyester Film Laminates offer good puncture resistance for coil and bobbin wrapping.

Tapes designed with Nomex® aramid paper combine high temperature resistance with high impregnation properties for insulation of e-motors, generators and transformers.

The natural conductivity, flexibility and malleability of foil tapes provide superior electromagnetic and radio frequency absorption and isolation as well as oxidation and corrosion resistance and are frequently used for EMI/RFI shielding, static charge draining and grounding by the printed circuit industry or in end connectors, shielded cabinets and devices.

Adhesives based on acrylics, rubber or silicone are most common with pressure sensitive adhesive tapes (PSA). Each adhesive type has special characteristics, benefits and limits that need to be considered. Acrylics provide good adhesion to polar surfaces such as metals, glass or polyesters and more. They provide good chemical, solvent and weathering resistance. Acrylic adhesives are an economic, high-performance solution but are limited in very high-temperature applications.

Rubber-based adhesives offer great initial tack and strong adhesion to a wide range of surfaces. Because of UV light vulnerability and lower maximum temperature resistance, they are mainly used in indoor applications with steady temperatures. They offer good moisture resistance and can easily be designed to be removable, repositionable or permanent.

Pressure sensitive silicone adhesives are the ideal choice when high temperature resistance is needed. Silicone PSA’s offer exceptional bonding strength, flexibility at lower temperatures, are resistant to UV and solvents. The costs for silicone adhesives are usually higher but they provide the highest temperature resistance compared to acrylic- or rubber-based PSA.

With your application and the electrical, mechanical and chemical stresses in mind, leverage our product selector to narrow down the options. Or dive deeper into characteristics, benefits and limits of acrylic-, rubber- and silicone-based adhesives, the world of electrical insulating tapes and the tests they undergo for oil filled transformers. Hopefully, this information will help you put together just the right ingredients for your preferred solution.