HP Xw6600 HP xw6600 Workstation Service and Technical Reference Guide - Page 59

Preventing ESD equipment damage, Personal grounding methods and equipment, Wrist straps, Heel straps

Page 59 highlights

Table 4-1 Static electricity Relative humidity Event 55% 40% 10% Walking across carpet Walking across vinyl floor Motions of bench worker 7,500V 3,000V 400V 15,000V 5,000V 800V 35,000V 12,000V 6,000V Removing bubble pack from PCB Packing PCBs in foam-lined box 7,000V 5,000V 20,000V 11,000V 26,500V 21,000V CAUTION: 700 volts can degrade a product. Preventing ESD equipment damage 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: ● Transport products in static-safe containers such as tubes, bags, or boxes, to avoid hand contact. ● Protect electrostatic parts and assemblies with nonconductive 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 containers. ● When handling or touching a sensitive component or assembly, ground yourself by touching the chassis. ● Avoid contact with pins, leads, or circuitry. ● Place reusable electrostatic-sensitive parts from assemblies in protective packaging or nonconductive foam. Personal grounding methods and equipment Use the following items to help prevent ESD damage to equipment: ● Wrist straps-These are flexible straps with a maximum of one megohm ± 10% resistance in the ground cords. To provide a proper ground, wear the strap 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, and boot straps-These 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. The following table shows typical static shielding protection levels. Table 4-2 Static shielding protection levels Method Voltage Antistatic plastic Carbon-loaded plastic 1,500V 7,500V ENWW Service considerations 49

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Table 4-1
Static electricity
Relative humidity
Event
55%
40%
10%
Walking across carpet
Walking across vinyl floor
Motions of bench worker
7,500V
3,000V
400V
15,000V
5,000V
800V
35,000V
12,000V
6,000V
Removing bubble pack from PCB
Packing PCBs in foam-lined box
7,000V
5,000V
20,000V
11,000V
26,500V
21,000V
CAUTION:
700 volts can degrade a product.
Preventing ESD equipment damage
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:
Transport products in static-safe containers such as tubes, bags, or boxes, to avoid hand contact.
Protect electrostatic parts and assemblies with nonconductive 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 containers.
When handling or touching a sensitive component or assembly, ground yourself by touching the
chassis.
Avoid contact with pins, leads, or circuitry.
Place reusable electrostatic-sensitive parts from assemblies in protective packaging or
nonconductive foam.
Personal grounding methods and equipment
Use the following items to help prevent ESD damage to equipment:
Wrist straps
—These are flexible straps with a maximum of one megohm ± 10% resistance in the
ground cords. To provide a proper ground, wear the strap 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, and boot straps
—These 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.
The following table shows typical static shielding protection levels.
Table 4-2
Static shielding protection levels
Method
Voltage
Antistatic plastic
Carbon-loaded plastic
1,500V
7,500V
ENWW
Service considerations
49