HP Compaq d220 MT, Справочное руководство

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Service Reference Guide, d200 336493-004 5–3
Identifying the Chassis, Routine Care, and Disassembly Preparation
5.2.2 Preventing Electrostatic Damage to Equipment
Many electronic components are sensitive to ESD. Circuitry design and structure determine the
degree of sensitivity. The following packaging and grounding precautions are necessary to
prevent damage to electric components and accessories.
■
To avoid hand contact, transport products in static-safe containers such as tubes, bags, or
boxes.
■
Protect all electrostatic parts and assemblies with conductive or approved containers or
packaging.
■
Keep electrostatic sensitive parts in their containers until they arrive at static-free stations.
■
Place items on a grounded surface before removing them from their container.
■
Always be properly grounded when touching a sensitive component or assembly.
■
Avoid contact with pins, leads, or circuitry.
■
Place reusable electrostatic-sensitive parts from assemblies in protective packaging or
conductive foam.
5.2.3 Personal Grounding Methods and Equipment
Use the following equipment to prevent static electricity damage to equipment:
■
Wrist straps are flexible straps with a maximum of one-megohm ± 10% resistance in the
ground cords. To provide proper ground, a strap must be worn snug against bare skin. The
ground cord must be connected and fit snugly into the banana plug connector on the
grounding mat or workstation.
■
Heel straps/Toe straps/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 them on both feet with a maximum of one-megohm ± 10% resistance between the
operator and ground.
5.2.4 Grounding the Work Area
To prevent static damage at the work area, use the following precautions:
■
Cover the work surface with approved static-dissipative material. Provide a wrist strap
connected to the work surface and properly grounded tools and equipment.
■
Use static-dissipative mats, foot straps, or air ionizers to give added protection.
■
Handle electrostatic sensitive components, parts, and assemblies by the case or PCB
laminate. Handle them only at static-free work areas.
■
Turn off power and input signals before inserting and removing connectors or test
equipment.
Static Shielding Protection Levels
Method Voltage
Antistatic plastic
Carbon-loaded plastic
Metallized laminate
1,500
7,500
15,000