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More information about RFI Shielding Wire Mesh

OVERVIEW

Copper shielding meshes: EMI-RFI shielding for electronic enclosures from small Faraday cages, to rooms, to complete buildings. These meshes are woven from commercially pure copper. Weave quality guaranteed to meet or exceed ANSI/AWCI-01-1992.

Stainless Steel shielding meshes: For CRT’s and shielded windows, these ultra thin materials are used. (for more information see our high transparency section).

SHIELDING EFFECTIVENESS GRAPH PDF

NASA Design Guide for Shielding PDF

RFI Shielding Wire Mesh - Tables 16 mesh copper Mesh per inch = 16 Wire diameter = .011 inch (.279mm) Opening size = .052x.052 inch (1.32x1.32mm) Percentage of open area = 68% Weight = .14 pounds per square foot (.684 kg per square meter) Standard rolls are 100 feet in length TWP part number for 36" width = 016X016C0110W36T TWP part number for 48" width = 016X016C0110W48T TWP part number for 60" width = 016X016C0110W60T TWP part number for 72" width = 016X016C0110W72T 16 mesh copper in 72" width is available in full rolls only Shielding Effectiveness of 16 Mesh .011 Copper Wire Cloth Shielding Effectiveness (db) Frequency 107 400 KHZ and below 100 1 MHZ 90 4 MHZ 80 10 MHZ 70 30 MHZ 60 100 MHZ 50 300 MHZ 40 1 GHZ 30 2.5 GHZ 20 10 GHZ Note: Maximum Shielding Effectiveness for copper screen is 107dB 22 mesh copper Mesh per inch = 22 Wire diameter = .015" Opening size = .030" Percentage of open area = 44% Weight = .38 pounds per square foot (1.83 kg per square meter) Standard rolls are 100 feet in length TWP part number for 36" width = 022X022C0150W36T TWP part number for 48" width = 022X022C0150W48T This mesh is used in the U.S. Government TEMPEST program. Shielding Effectiveness of 22 Mesh .015 Copper Wire Cloth Shielding Effectiveness (db) Frequency 107 400 KHZ and below 107 1 MHZ 97 4 MHZ 87 10 MHZ 77 30 MHZ 66 100 MHZ 56 300 MHZ 46 1 GHZ 40 2.5 GHZ 27 10 GHZ Note: Maximum Shielding Effectiveness for copper screen is 107dB 100 mesh copper Mesh per inch = 100 Wire diameter = .0045 inch (.114mm) Opening size = .0055x0.0055 inch (.14x0.14mm) Percentage of open area = 30.3% Weight = .14 pounds per square foot (.684 kg per square meter) Standard rolls are 100 feet in length TWP part number for 36" width =100X100C0045W36T TWP part number for 72" width =100X100C0045W72T Shielding Effectiveness of 100 Mesh .0045 Copper Wire Cloth Shielding Effectiveness (db) Frequency 107 400 KHZ and below 107 1 MHZ 105 4 MHZ 95 10 MHZ 90 30 MHZ 80 100 MHZ 65 300 MHZ 55 1 GHZ 48 2.5 GHZ 30 10 GHZ Note: Maximum Shielding Effectiveness for copper screen is 107dB

SHIELDING EFFECTIVENESS GRAPH PDF

RFI Shielding Wire Mesh - Uses

• Faraday cages
• Metal detectors
• EMI shielding
• RFI shielding
• Shielded rooms
• Tempest shielding
• Shielding satellite antennas from terrestrial interference (TI)
• Cable wrapping and display shielding

RFI Shielding Wire Mesh - Cutting

Our copper RFI meshes (like 16 mesh, 22 mesh, and 100 mesh) are easily cut with scissors and the material presents no special handling difficulties.

High transparency (optical shielding stainless steel meshes like 50mesh, 80 mesh and 100 mesh) are extremely delicate with fine wires with relatively large openings. This makes it difficult to handle and cut to size or shape and can result in wrinkles and distortions. We have had some success in minimizing cutting difficulties by taping these optical stainless steel meshes to a paper backing and cutting through the paper and mesh simultaneously.

A common scissor can be used to cut these meshes.

RFI Shielding Wire Mesh - Installation

Although we are not application engineers, we have the following examples of how some of our customers have installed the copper mesh in some shielded enclosures and rooms. The flexible wire mesh is installed on all four walls, the ceiling and floor with each mesh panel overlapping the next by three inches.

The mesh is fastened securely on 12-inch centers with staples and adhesive or casein glue. Each of the four corners has a strap that leads to an earthen ground. These grounding straps are formed by folding a 9-inch wide length of mesh into a three-inch strip.

One end of strap is attached to the mesh in the room corners, mechanically or with solder, and the other ends are attached to ground by a licensed electrician. The mesh is often covered with sheet rock to protect it.

TWP INC is only a wire mesh supplier and fabricator. We have no RFI engineers in our staff, but we suggest that you consult an RFI/EMI expert.

RFI Shielding Wire Mesh - Samples

TWP Inc. will provide samples for your testing and inspection. RFI shielding mesh sample size is 3 inch x 3 inch. Credit cards only please. The cost is $8 per sample ordered For the quickest service, please order your samples on-line.

More Shielding Information

Very useful for the lay person are:

Radio Frequency Interference: How to Find It and Fix It. Ed Hare, KA1CV and Robert Schetgen, KU7G, editors The American Radio Relay League, Newington , CT ISBN 0-87259-375-4 (c) 1991, second printing

1992 Federal Communications Commission Interference Handbook (1991) FCC Consumers Assistance Branch Gettysburg, PA 17326 717-337-1212

MIL-STD-188-124B in preparation (includes information on military shielding of tactical communications systems) Superintendent of Documents US Government Printing Office Washington, DC 20402 202-783-3238

Information on shielding a particular piece of consumer electronic equipment may be available from the: Electronic Industries Association (EIA) 2001 Pennsylvania Ave NW Washington, DC 20006