Compaq 420CX 486 DX4/75 MHZ 420 MB 8 MB 10.4 Personal Computer User Manual


 
Grounding Methods
The method for grounding must include 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 2-2. Static-Shielding Protection Levels
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Method Voltages
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Anti-static Plastic 1,500
Carbon-Loaded Plastic 7,500
Metallized Laminate 15,000
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Grounding Workstations
To prevent static damage at the workstation, follow these precautions:
o Cover the workstation with approved static-dissipative material.
Provide a wrist strap connected to the work surface and properly
grounded tools and equipment.
o Use static-dissipative mats, heel straps, or air ionizers to give added
protection.
o Handle electrostatic sensitive components, parts, and assemblies by the
case or PCB laminate. Handle them only at static-free workstations.
o Avoid contact with pins, leads, or circuitry.
o Turn off power and input signals before inserting and removing
connectors or test equipment.
o Use fixtures made of static-safe materials when fixtures must directly
contact dissipative surfaces.
o Keep work area free of nonconductive materials such as ordinary plastic
assembly aids and Styrofoam.
Grounding Equipment
Use the following equipment to prevent static electricity damage to the
equipment:
Wrist Straps are flexible straps with a minimum of 1 megohm +/-10%
resistance to the ground cords. To provide proper ground, a strap must be
worn snug against the skin. On grounded mats without banana-plug
connectors, connect a wrist strap with alligator clips.
Heelstraps/Toestraps/Bootstraps can be used at standing workstations and
are compatible with most types of boots and shoes. On conductive floors or