Compaq Portable 486 Compaq Portable 486c Personal Computer Maintenance and Ser - Page 55

grounding are necessary precautions to prevent damage. Use the following precautions to protect equipment from static damage: o To avoid hand contact, transport products in static safe containers such as tubes, bags, or boxes. o Protect all electrostatic parts and assemblies by conductive or approved containers or packaging. o Keep electrostatic sensitive parts in their containers until they arrive at static free stations. o Place items on a grounded surface before removing them from their container. o Always be properly grounded when touching a sensitive component or assembly. o Place reusable electrostatic sensitive parts from assemblies in protective packaging or conductive foam. Use transporters and conveyors made of antistatic belts and metal roller bushings. Mechanized equipment used for moving materials must be wired to ground and proper materials selected to minimize static charging. When grounding is not possible, use an ionizer to dissipate electric charges. Preventing Damage to Drives To prevent static damage to diskette drives and fixed disk drives, handle drives gently and perform the following static guarding techniques: o Store drives in their original shipping containers. o Avoid dropping the drive from any height onto any surface. o Handle drives on surfaces which have at least one inch of shock proof foam. o Always place drives PCB assembly side down on the foam. Grounding Methods Methods for grounding must include either a wrist strap or a foot strap at a grounded workstation. When seated, wear a wrist strap connected to a grounded system. When standing, use footstraps and a grounded floor mat. Table 5-2 lists different antistatic materials and their shielding protection levels. Table 5-2. Static Shielding Protection Levels Method Voltages Antistatic plastic 1,500 Carbon loaded plastic 7,500 Metallized laminate 15,000