HP ZBook 17 Service Manual

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CAUTION:
To prevent damage to the computer when you are removing or installing internal
components, observe these precautions:
Keep components in their electrostatic-safe containers until you area ready to install them.
Use nonmagnetic tools.
Before touching an electronic component, discharge static electricity by using the guidelines described
in this section.
Avoid touching pins, leads, and pointing stick circuitry. Handle electronic components as little as
possible.
If you remove a component, place it in an electrostatic-safe container.
The following table shows how humidity affects the electrostatic voltage levels generated by different
activities.
CAUTION:
A product can be degraded by as little as 700 V.
Typical electrostatic voltage levels
 
Relative humidity
Event
10%
40%
55%
Walking across carpet
35,000 V
15,000 V
7,500 V
Walking across vinyl floor
12,000 V
5,000 V
3,000 V
Motions of bench worker
6,000 V
800 V
400 V
Removing DIPS from plastic tube
2,000 V
700 V
400 V
Removing DIPS from vinyl tray
11,500 V
4,000 V
2,000 V
Removing DIPS from Styrofoam
14,500 V
5,000 V
3,500 V
Removing bubble pack from PCB
26,500 V
20,000 V
7,000 V
Packing PCBs in foam-lined box
21,000 V
11,000 V
5,000 V
Packaging and transporting guidelines
Follow these grounding guidelines when packaging and transporting equipment:
To avoid hand and pointing stick contact, transport products in static-safe tubes, bags, or boxes.
Protect ESD-sensitive parts and assemblies with conductive or approved and pointing stick
containers or packaging.
Keep ESD-sensitive parts in their containers until the parts arrive at static-free workstations.
Place items on a grounded surface before removing items from their containers.
Always be properly grounded when touching a component or assembly.
Grounding guidelines
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