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 contact, transport products in static-safe tubes, bags, or boxes.
●
Protect ESD-sensitive parts and assemblies with conductive or approved 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.
●
Store reusable ESD-sensitive parts from assemblies in protective packaging or nonconductive
foam.
●
Use transporters and conveyors made of antistatic belts and roller bushings. Be sure that
mechanized equipment used for moving materials is wired to ground and that proper materials are
selected to avoid static charging. When grounding is not possible, use an ionizer to dissipate
electric charges.
Workstation guidelines
Follow these grounding workstation guidelines:
●
Cover the workstation with approved static-shielding material.
●
Use a wrist strap connected to a properly grounded work surface and use properly grounded tools
and equipment.
●
Use conductive field service tools, such as cutters, screwdrivers, and vacuums.
ENWW
Preliminary replacement requirements
25
Содержание DesignJet 500
Страница 1: ...HP 500 Notebook PC Maintenance and Service Guide ...
Страница 90: ...ENWW Phillips PM2 0 9 0 screw 85 ...
Страница 95: ...Where used 4 screws that secure the heat sink to the base enclosure 90 Chapter 8 Screw listing ENWW ...
Страница 104: ...Universal Serial Bus Pin Signal 1 5 VDC 2 Data 3 Data 4 Ground ENWW Universal Serial Bus 99 ...