HP ProDesk 400 G7 SFF, Maintenance And Service Manual

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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 static electricity
damage to electronic components.
● 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.
Personal grounding methods and equipment
Use this equipment to prevent static electricity damage to electronic components.
●
Wrist straps are flexible straps with a maximum of 1 MΩ ±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 1 MΩ ±10% resistance between the operator and ground.
Table 3-2 Static shielding protection levels
Static shielding protection levels
Method Voltage
Antistatic plastic
Carbon-loaded plastic
Metallized laminate
1,500
7,500
15,000
Grounding the work area
To prevent static damage at the work area, use these 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.
●
Use fixtures made of static-safe materials when fixtures must directly contact dissipative surfaces.
ENWW Electrostatic discharge information 13