EMI Shielding

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Protecting electronic components, wiring and cables from receiving or transmitting unwanted electromagnetic signals is the primary function of all electromagnetic (EMI) shielding materials.

Electromagnetic interference consists of two components, an electric field that can be transmitted through space or along a conductor and a magnetic field that can disrupt the flow of a signal along a conductor. The most common form of EMI interference encountered by electronic system designers tends to be radiate electric fields (e-fields). These unwanted signals become problematic when a system is operating in close proximity to a radiated high strength signal source which corrupts the desired signals of an operating system. Unlike magnetic fields which strength and effect drops with the square of the distance, electric fields can travel over long distances (miles) and corrupt desirable system signals. Sometimes these unwanted signals are generated within an electronic system itself and radiate out into the environment corrupting other systems. In other instances, stray interference signals enter a system from the outside environments and corrupt the system operation itself. In either case, providing and effective EMI shield can mitigate these interference signals either in or out.

Electric (e-field) EMI shields work by placing an electrically conductive metallic shell around all or part of the system components and attaching this shell to ground. E-field interference signals striking this shell attempt to build an electric charge on this shell. But since the shell is grounded the interference signal energy is shunted to ground rather than being allowed to coupling with the system components which reduces the interference signal strength to the point of making the signal harmless.

All electrical interconnect wiring acts as an antenna and can receive or radiate internally generated signals or outside stray signals. It’s the electrical wirings ability to act as an antenna that makes it the biggest culprit (although not the only one) in picking up stray signals and introducing them into a system or radiating a signal out of the system. Providing a good EMI shield around these long linear antennas is the first place to consider adding an EMI shield.

Zippertubing EMI Shield Materials are the solution.

Zippertubing’s unique wrap-around product line makes adding EMI Shielding material to our Jacket types a snap and the design provides customers with easy to install EMI solutions. The design is also an ideal delivery system since it can be added during system fabrication as well as field retrofit of in service equipment.

This design concept allows incorporation of wide variety of EMI Shielded materials including Aluminum Foil, Tin/Copper and Stainless Steel Wire Mesh, Nickel/Copper and Nonmagnetic platted Copper metallized fabric materials. The Zippertubing concept can be configured for the very large (12”+ diameter), for large cable groupings to the very small utilizing our heat shrinkable types for diameters down to .090 inch for individual circuit leads.

The mix and match of materials combined with a large variety of closure options, grounding options and a willingness to create customer specific shapes results in literally thousands of configuration possibilities. View many of Zippertubing's proven EMI shielding solutions, or click here if you are in need of a completely custom EMI shielding solution.