4–4
Maintenance and Service Guide
Removal and replacement procedures
Workstation guidelines
Follow these workstation grounding guidelines:
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Cover the workstation with approved static-shielding material.
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Use a wrist strap connected to a properly grounded work surface, and use properly grounded tools and
equipment.
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Use conductive field service tools, such as cutters, screwdrivers, and vacuums.
■
When fixtures must directly contact dissipative surfaces, use fixtures made only of static-safe materials.
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Keep the work area free of nonconductive materials, such as ordinary plastic assembly aids and Styrofoam.
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Handle ESD-sensitive components, parts, and assemblies by the case or PCM laminate. Handle these items
only at static-free workstations.
■
Avoid contact with pins, leads, or circuitry.
■
Turn off power and input signals before inserting or removing connectors or test equipment.
Equipment guidelines
Grounding equipment 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. Wrist straps are flexible straps with a
minimum of one megohm ±10% resistance in the ground cords. To provide proper ground, wear a strap snugly
against the skin at all times. On grounded mats with banana-plug connectors, use alligator clips to connect a
wrist strap.
■
When standing, use foot straps and a grounded floor mat. Foot straps (heel, toe, or boot straps) can be used at
standing workstations and are compatible with most types of shoes or boots. On conductive floors or
dissipative floor mats, use foot straps on both feet with a minimum of one megohm resistance between the
operator and ground. To be effective, the conductive strips must be worn in contact with the skin.
The following grounding equipment is recommended to prevent electrostatic damage:
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Antistatic tape
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Antistatic smocks, aprons, and sleeve protectors
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Conductive bins and other assembly or soldering aids
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Nonconductive foam
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Conductive tabletop workstations with ground cords of one megohm resistance
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Static-dissipative tables or floor mats with hard ties to the ground
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Field service kits
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Static awareness labels
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Material-handling packages
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Nonconductive plastic bags, tubes, or boxes
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Metal tote boxes
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Electrostatic voltage levels and protective materials
The following table lists the shielding protection provided by antistatic bags and floor mats.
Material
Use
Voltage protection level
Antistatic plastic
Bags
1,500 V
Carbon-loaded plastic
Floor mats
7,500 V
Metallized laminate
Floor mats
5,000 V
