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What are some of the factors to take care of while designing an EMI/RFI shielded Enclosure? Answered

are there any constraints on material used and wall thickness?


The only thing is that the mesh be very fine, and that there are no 'leaks' where EMI/RFI can get through. You can ground the box to existing plumbing pipes or electrical conduits. You will need to have a door to get in/out of the box, so there should be some contact 'fingers' to make a good electrical connection. Construction can be as simple or as eloborate as you want it to be, which can be a simple wood frame with the mesh stapled to it to hold it on, to a complete construction project with concrete walls and steel doors. Remember to do all sides (floor, ceiling, and all four walls) in conductive mesh, and bond them electrically together. As a quick aside; if you don't ground the mesh correctly, it will become a really big inductively-coupled antenna. Any power coming into the box (lights, power for the electronic devices, test equipment, etc.) needs to be filtered HEAVILY! Lighting should not be gas-filled (neon/flourescent) tubes or bulbs, as they create EMI/RFI.

I think what you want is a Faraday cage. a cage or enclosure built of wire mesh or other conductive material. I'm not an expert on there construction but they could be used to create a RF free area or protect from EMP. I think you need the cage to either be on the ground or a complete cube and it must be tied to earth ground (electrically).