Modular EM RF Shielded Enclosure

A semi-permanent system that provides over 70dB attenuation over the range of 20MHz to 18 GHz (IEEE™ 299)

An RF shielded tent enclosure to reduce the radio frequency (RF) environment during Electromagnetic Compatibility (EMC) testing, the Modular EM RF Shielded Enclosure can be scaled from 8’ x 8’ x 8’.

Modular EM RF Shielded Enclosure from Select Fabricators, Inc.

Features:

  • Semi-permanent, easier to install, store and transport than metal wall chambers
  • Lower in cost and weight than a permanent welded shielded chamber
    • 10:1 weight ratio to a welded screen room
  • Removable “hardware cloth” panels
  • Internal frame
  • Over 70dB attenuation over the range of 20MHz to 18 GHz (IEEE™ 299)
  • Constructed with Nova Select™ acrylic coated Ag/Cu/Ni conductive fabric.
  • Optional cleaning to ISO Class 7 (Class 10,000 –Fed. Std. 209)
  • Patent Pending: July 2016
  • Mil-Std. 461G-Appendix A compatible
“When equipment is too large or requires special provisions (loads, drives, water, emission of toxic fumes and such), testing in a typical semi-anechoic room may not be feasible. Temporary screen rooms consisting of hardware cloth can be built around the test area to reduce the ambient for radiated emission testing and to contain the RF field during radiated susceptibility testing. Since the room may be highly reflective, care must be taken to identify any resonances. Several antenna positions may be required in order to reduce the effect of the resonances.” United States Military – MIL-STD-461G appendix A (page 165). www.interferencetechnology.com

There are five parts to the system, an internal frame, metal ground plane floor, removable fabric panels, collapsible anteroom and internally suspended anechoic foam panels.

1. Internal Frame

A free-standing, aluminum channeled, post and beam Series 300 frame supports the weight of port plates, multiple vents for both intake and exhaust, the modular fabric panels and RF anechoic foam panels. Internal frame channels are used to create a clamping system with fabric overlaps to provide an RF tight seal. The patent pending design conductively connects every horizontal and vertical frame member in the system.

2. Metal Ground Plane Floor

An aluminum sheet ground plane system is conductively connected to the frame and modular fabric panels allowing heavy units to enter and exit. The floor plane system uses a rabbet edge design and connected using EMI shielding gaskets and flush-mount clamping bars. The perimeter floor plates contain hardware that clamp to the tent’s modular fabric panels which establishes a RF tight seal.

3. Removable Fabric Panels

The removable panels for the modular tent enclosure are made with NovaSelect™ conductive silver/copper/nickel fabric, externally coated with an acrylic that minimizes particle shedding and metal plating breakdown. The flexible “hardware cloth” is cleanroom ISO Class 7 (Class 10,000 –Fed. Std. 209) compatible. Every modular panel has stainless steel grommets installed around the outside perimeter to allow for stud/clamp connection to frame system and aluminum panel floor system.

The single door / double row flexible magnet seal (US Pat. No. 9,029,714) is a separate detachable panel and uses the aluminum bar clamping system on larger size enclosures. Because each panel is conductively connected to each other, the equipment door does not require a threshold, facilitating access.

4. Modular Anteroom

An external anteroom can be added for access once the main door has been secured. The anteroom is permanently attached to a modular panel connecting the unit to the internal frame and aluminum ground plane floor. The anteroom can optionally accordion fold towards main chamber to help minimize the footprint.

External anterooms include the standard conductive fabric floor with heavy duty vinyl protective layering on top and bottom. All four walls and ceiling inside the anteroom can be covered with optional lightweight fire barrier or ESD material.

5. Anechoic Foam Panels

Anechoic foam panels are installed on internal frame system as needed. Encased when specified, to prevent shedding and comply with ISO Class 7 (Class 10,000 –Fed. Std. 209) cleanroom specifications,