Generating Static Electricity; Preventing Electrostatic Damage To Equipment - HP ZBook 15u Maintenance And Service Manual

IMPORTANT:
observe these precautions:
Keep components in their electrostatic-safe containers until you are ready to install them.
Before touching an electronic component, discharge static electricity by using the guidelines described in this
section.
Avoid touching pins, leads, and circuitry. Handle electronic components as little as possible.
If you remove a component, place it in an electrostatic-safe container.

Generating static electricity

Note the following:
Different activities generate different amounts of static electricity.
●
Static electricity increases as humidity decreases.
●
Table 4-1 Static electricity occurrence based on activity and humidity
Event
Walking across carpet
Walking across vinyl floor
Motions of bench worker
Removing DIPs from plastic tube
Removing DIPs from vinyl tray
Removing DIPs from Styrofoam
Removing bubble pack from PCB
Packing PCBs in foam-lined box
Multiple electric components can be packaged together in plastic tubes, trays, or Styrofoam.
NOTE: As little as 700 V can degrade a product.

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.
●
To prevent damage to the device when you are removing or installing internal components,
Relative humidity
55% 40%
7,500 V 15,000 V
3,000 V 5,000 V
400 V 800 V
400 V 700 V
2,000 V 4,000 V
3,500 V 5,000 V
7,000 V 20,000 V
5,000 V 11,000 V
Electrostatic discharge information
10%
35,000 V
12,000 V
6,000 V
2,000 V
11,500 V
14,500 V
26,500 V
21,000 V
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