USC-26 RFI/EMI Shielding System

Universal Shielding's USC-26 RFI/EMI shielding system is designed to meet or exceed the vast majority of shielding requirements. This system is available in both standard modular enclosures and custom-designed modular enclosures to meet exacting specifications in government, industry, research and development, university or hospital use. Rigid, steel-clad, 4-foot structural panels with steel framing form the modular USC-26 RF shielded enclosures. Weldnuts on the corner and intermediate framing members eliminate screws that penetrate the framing members. In addition, this exclusive weldnut feature provides a structure that is tamper-proof from the outside... an important consideration in Secure Communications. Our enclosures can be designed to accommodate raised floors for computer installations, suspended ceilings with recessed lighting, and specially-designed channels for installing acoustic and/or anechoic absorbers. To the right is a typical performance curve for the USC-26 shielded enclosure when tested in accordance with MIL-STD-285 and NSA 65-6.

Shielded Doors

A shielded enclosure is only as effective as its access portals. USC research and engineering has developed doors that provide attenuation characteristics equal to the enclosure itself, and are mechanically and aesthetically acceptable.

Door Construction

To achieve the attenuation levels required, our doors are equipped with a minimum of two rows of beryllium copper "fingers" around the periphery of the door. In the closed position, the fingers contact the door frame to assure an RFI/EMI leak-proof seal. The following is a type of door/frame construction offered by USC:

Type RCM 154

A brass extrusion is mounted on the periphery of the door frame. This extrusion houses two rows of "fingers" which are concealed from accidental damage. The door itself has a "knife-edged" extrusion around its perimeter which mates with the fingers within the frame when the door is closed. This design results in a damage-free closure seal with highly efficient prevention of RFI/EMI leakage.

Latching Mechanism

USC enclosure doors are equipped with a 3-point latching mechanism for tight, RFI-EMI-secure closing. Bearing surfaces, rollers and door cams are of case-hardened tool steel, designed to provide years of trouble-free operation with no loss of attenuation capability due to friction and wear. Our doors are extremely easy to operate; they require less than 20 pounds of force on the handle.

Sizes Available

Our standard single-personnel-door provides a 3'0" by 7'0" high clear opening; and our standard double door provides 6'0" by 7'0" clear opening. In addition, any size door may be supplied on special order to meet particular customer requirements.

Automatic Doors

USC can supply shielded doors with power operated latch/unlatch mechanisms-also, fully automatic doors with open and close cycling. These doors are designed to utilize a variety of sensor devices.

Panels and Framing Members

The panels are laminates of electrolytically deposited zinc, sheet metal laminated to both surfaces of 3/4 inch structural core. Wall, floor and ceiling panels are of the same construction.

The panels are joined and supported by specially designed members that clamp the edges of the panels and provide constant, low impedance joints with the shielding elements of the panels.

The steel framing-joinging system consists of four types of channels: "M", "U", "hat" and "flat", with the "M" and "U" channels forming the corner joints and the "hat" and "flat" channels forming the intermediate joints. These channels are made of 1/8 inch zinc-plated steel and have eleven grooves or serrations running lengthwise along each side of the contacting surface. The "M" and "hat" channels have weldnuts welded to the inside of the channels on 3-inch centers. The "U" and "flat" channels have holes punched on 3-inch centers to correspond to the positioning of the weldnuts. The "flat" channel has a convex contour for positive spring tension, insuring an R.F. tight enclosure. Screw fasteners of either zinc-plated or cadium-plated steel 1/4-inch in diameter are provided to complete the assembly. These screw fasteners do not penetrate the "M" or the "hat" channels.

At all corner intersections of walls, floor or ceiling, a one-piece factory pre-welded corner section is provided. This corner consists of sections of "M" and "U" channels welded together and zinc-plated.

The entire steel frame work is supplied with integral interconnecting tabs and weld screws and is assembled from the interior using only a posi-drive head screwdriver.

This interconnecting system enables rapid assembly and installation of the enclosure.

Ancillary Equipment

Filters

Every electrical power, signal, telephone and communication wire entering a RF shielded enclosure requires a filter to prevent conducted signals from entering the enclosure. Filters can be supplied to meet MIL-F-15733E, MIL-STD-220A, and DCA Red/Black Engineering-Installation Criteria DCA CIR C175-6A. Filters will provide the proper attenuation to conform with the shielded enclosure specification.

Ventilation

Air is transmitted thru the enclosure through wave guide air vents which provide RF attenuation equal to the enclosure. We can supply exhaust fans or air conditioning systems to maintain a constant environment within the enclosure.

RF Connector Panels

RF Connector Panels are provided which are easily removeable and contain Type N, BNC, UHF, etc. connectors. Quantity and type to meet customer's requirements.

Penetration

Compressed air, water, and waste-disposal, enter a shielded enclosure through specially designed penetrations. These penetrations do not affect the related attenuation of the enclosure.

Lighting

USC can provide incandescent and RFI suppressed fluorescent fixtures.

Architectural Treatments

We can provide acoustical tile, hardboard wainscoating, pre-finished paneling, vinyl asbestos floor tile, computer floors, etc. on the interior of enclosures.

Shielded Electronic Cabinets

USC manufactures various sizes of shielded cabinets to shield equipment from extraneous signals.

Services Offered

Engineering

USC engineering staff offers its services to design from the smallest pre-fabricated unit for an R&D lab to the largest and most complex custom-built installation encompassing electrical, air conditioning, acoustic, and sprinkler systems, etc.

Installation

USC offers complete turn key installation of its enclosures at a pre-determined installation cost.

Supervision

USC can provide installation supervision to expedite construction and assure that the design performance is met.

RF Testing

USC can provide a test engineer with the necessary equipment to certify enclosures to MIL-STD-285, MIL-E-4957, MIL-E-8881, NSA65-6, NSA65-5 or to special test plans.