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12R Series Rugged COTS Chassis

PRODUCTOVERVIEW The COTS 12R series is a high quality and cost-efficient rugged package for all VME/VME64x, VXI, VXS, CompactPCI and CompactPCIExpress applications.The rugged product line includes 2U-14U models for both 6U and 9U cards. Intended to withstand the demands of a military environment, the 12R series is designed to meet benchmark military standards. The 12Rs use honeycomb filters, braided gasketing, and metal impregnated gasket sheets to seal off every external seam to ensure compliance to MIL-STD-461D. The 12R1 is a light-weight verssion with extruded parts that are less dense. The 12R2 uses thicker components that are spot welded. All of the chassis are compliant to the IEEE 1101.10/.11 mechanical specifications and IEEE 1101.2 for conduction cooled versions. Test reports and performance specifications are available upon request. The 12R platforms use electrostatic dust filters, honeycomb EMI filters, braided gaskets and metal impregnated flat gaskets to seal off every external seam to ensure compliance to MIL-STD-461D. The rugged designs meet the requirement for shock, vibration and structural integrity per MIL-STD-810F, MIL-STD-167 and MIL-STD-901D. The 12R series shells are build from aluminum sheets, extrusions and, die-castings. The parts are jointtogether by rivetting, spot-welding and stainless steel screws. All removable parts are equipped with captive screws. Furthermore the 12R series have MIL-grade components, system monitoring LEDs, a powerful, efficient cooling system, accepting up to 20 boards, and are available with fix mounted or shock isolated card cages and drive bays.
SHOCK & VIBRATION Every piece of electronic equipment needs to be able to withstand the physical demands of the environment in which it is to be used. In order to protect the equipment and its contents from its insidious effects, Elma uses passive isolation systems such as elastomeric dampers, rope coil isolators and air springs. Most commonly incorporated are rope coil isolators that when deflected, friction between the wire strands produces a damping effect. They offer large deflections in relation to their size, they are also not affected by temperature extremes and resist attack by solvents, chemicals ozone etc.
EMC Shock coil isolators Electromagnetic Interference (EMI) is of paramount importance, especially in a military environment with mission critical applications where spurious emissions can seriously impair a system's integrity. Elma commonly integrates shielding gaskets into the enclosure design to provide a continuous conductive ground contact surface for all removable panels thereby restricting the aperture size of any seams. The gasket is a braided wire mesh with elastomer core in a compression configuration under a flat panel. Closely spaced screws preserve the shielding effectiveness of the enclosure. Line filters are also incorpo- rated that provide a high degree of attenuation (insertion loss) to conducted common mode (line to ground) and differential mode (line to line) emissions and meets MIL-STD-461D. Other options suchas integrating honeycomb's EMC filters on all air intake and air exhaust openings, high-grade powersupplies that meet or exceed the conducted emissions, and shielded connectors and cable assemblies for I/O cabling requirements. Elma is also careful to employ proper grounding techniques and adequate number of ground points, provide careful selection of components like fans, power on/off switches, indicator LEDs etc. based on their shielding effectiveness or compliance to MIL-STD-461D. I/O Cabling
I/O CABLING I/O cabling is a key component for almost all enclosures, enabling them to interact with a variety of equipment. The number of cables, the type of connectors, the bend radius required and the routing are all analyzed and evaluated before the design begins. Cable channels or clamps are provided to manage the cable bundle and keep it from interfering with the air flow and access to internal components. A patch panel approach to mounting of the connectors on the rear panel lends tremendous flexibility to the cabling configuration while at the same time, facilitating easy maintenance.
OTHER ELEMENTS Elma also incorporates many other design elements into our Rugged chassis. This includes using stainless steel hardware, conformal coating, and galvanicly compatible materials when harsh environments demand them. Other tactics to limit salt fog, fungus and moisture corrosion include hermetically sealed power switches, reset switches and other actuators. Elma’s optional drip-proof louvered panels meet International Protection 53code according to IEC 60529 specifications. Elma chooses long lasting components to maximize MTBF and minimize MTTR. Louvred panels
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