HP 285 Maintenance and Service Guide - Page 18

Preventing electrostatic damage to equipment, Personal grounding methods and equipment

Page 18 highlights

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. 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. Method Antistatic plastic Carbon-loaded plastic Metallized laminate Static Shielding Protection Levels Voltage 1,500 7,500 15,000 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. ● Use fixtures made of static-safe materials when fixtures must directly contact dissipative surfaces. ● Keep work area free of nonconductive materials such as ordinary plastic assembly aids and Styrofoam. ● Use field service tools, such as cutters, screwdrivers, and vacuums, that are conductive. 10 Chapter 3 Routine care, SATA drive guidelines, and disassembly preparation

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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 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.
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.
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 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.
Use
fixtures
made of static-safe materials when
fixtures
must directly contact dissipative surfaces.
Keep work area free of nonconductive materials such as ordinary plastic assembly aids and Styrofoam.
Use
field
service tools, such as cutters, screwdrivers, and vacuums, that are conductive.
10
Chapter 3
Routine care, SATA drive guidelines, and disassembly preparation