Enclosure chassis

The EPA regulation prohibits more than 2 grams per test to escape into the atmosphere (114). The test consists of a diurnal cycle of 1 hour where the temperature of the fuel is raised from 15.6 to 28.9°C during a 17 mile mn on a chassis dynamometer. An immediate hot soak in a shed enclosure follows the dynamometer mn. 

Where clock-radios (figure 30) are employed, a variety of significant debris may be discovered. The bulk of all radio enclosures are manufactured cither from wood or plastics and these would, therefore, disintegrate in a fire of any magnitude. Most of these radios arc built on a rather heavy steel or aluminum chassis, and various components are often riveted to this metal base. A normal superheterodyne receiver will probably include a double-section variable capacitor having a radier heavy mounting. Carbon resistors or certain metal-encased capacitors may come through the fire reasonably intact. Parts of the clock... 

For document handling applications, there are several components for which PAB s are suited. These include bases and chassis, which require high modulus pen bodies and optical devices, which require excellent dimensional stability moving parts that require lubricity and wear resistance and paper paths that require electrostatic dissipation (BSD). Similar requirements occur for related components in computers. Electromagnetic Interference (EMI) shielding is required for computer enclosures and printed circuit boards. Among the more common PAB s specified for these applications are PC/ABS and PPE/PS. 

How much improvement might be expected from using the chassis of an enclosure for cooling This depends substantially on the enclosure construction and the location of the chassis screw with respect to the hot component. In one example, a device was cooled with a thermal screw that connected between a hard drive PCB and the hard drive enclosure. Connecting the device thermally to the hard disk drive resulted in a 10 percent thermal enhancement. 

Environment. This will determine the enclosure type.The open-chassis type is also available for installation in other enclosures. 

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