Minimizing the Effects of Openings

The shielding effectiveness of an enclosure is a function of the wavelength of the frequencies involved versus the length of the longest dimension of openings. One common example is the seam opening occurring between the door and the sash of an electronic cabinet. Shielding gaskets are very low resistance connectors matching surfaces which; when installed, make the surface appear as one continuous RF absorbing surface.

The graph below displays the maximum shielding effectiveness possible from a given size opening (slot) in an enclosure.

Shielding Effectiveness vs. Frequency as a Function of Slot Length

It can be seen from the information above that the shielding effectiveness increases as the size of the opening is reduced. In order to achieve the same performance as a small opening, the slot must be coupled electrically across its opposing surfaces. This can be accomplished by using conductive fasteners or gaskets. Gaskets are usually the most common choice. They offer a continuous coupling along the full length of the slot while permitting the opposing surfaces to be separated easily for access to the components contained within. See the photo below.

Top view of electronic enclosure door with typical shielding gasket installation.

Find a Product

Inches Millimeters

Gap: The space between mounting and mating surfaces when in the compressed position.

Gap Size:

Mount Size: The amount of available space for mounting the part, including space for expansion of product when compressed.

Mount Size:

Mount Method: The desired method of attachment (i.e. clip-on, transfer adhesive, conductive transfer adhesive, solder, weld, or the use of hardware)

Mount Method: -- Mount Method --

Resources

• Conductive Adhesive Transfer Tape
• Pressure Sensitive Adhesive Transfer Tape
• Copper Beryllium
• Copper Nickel Tin
• Kimmel Gerke Associates, Ltd.
• IEEE
• RoHS

Contact