Service Considerations; Read Cautions, Warnings, And Safety Precautions; Electrostatic Discharge Information - HP xw4200 Service And Technical Reference Manual

Service Considerations

The following sections discuss service considerations that should be reviewed and practiced before
removing and replacing any system components.
WARNING! When lifting or moving the workstation, do not use the front bezel as a handle or lifting point.
Lifting the workstation from the front bezel or lifting it incorrectly could cause the unit to fall and harm the
user and damage the workstation. To properly and safely lift the workstation, lift it from the bottom of the
unit.

Read Cautions, Warnings, and Safety Precautions

For your safety, you must review the
components of the workstation. Also, review the Safety and Regulatory Guide that came with your
workstation for more information.

Electrostatic Discharge Information

A sudden discharge of static electricity from your finger or other conductor can destroy static-sensitive
devices or microcircuitry. Often the spark is neither felt nor heard, but damage occurs. An electronic
device exposed to electrostatic discharge (ESD) might not appear to be affected at all and can work
perfectly throughout a normal cycle. The device might function normally for a while, but it has been
degraded in the internal layers, reducing its life expectancy.
Networks built into many integrated circuits provide some protection, but in many cases, the discharge
contains enough power to alter device parameters or melt silicon junctions.
Generating Static
The following table shows that:
Different activities generate different amounts of static electricity.
Static electricity increases as humidity decreases.
Table 4-1
Generating Static Electricity
Event
Walking across carpet
Walking across vinyl floor
Motions of bench worker
Removing bubble pack from PCB
Packing PCBs in foam-lined box
NOTE: 700 volts can degrade a product.
68 REMOVAL AND REPLACEMENT
"Important Safety Warnings" on page vii
Relative Humidity
55% 40%
7,500 V 15,000 V
3,000 V 5,000 V
400 V 800 V
7,000 V 20,000 V
5,000 V 11,000 V
before accessing the
10%
35,000 V
12,000 V
6,000 V
26,500 V
21,000 V