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Compaq 2800 User Manual

Page 77

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Removal and Replacement Preliminaries

Maintenance and Service Guide

4–7

Nonconductive plastic bags, tubes, or boxes

Metal tote boxes

Electrostatic voltage levels and protective materials

Table 4-1 shows how humidity affects the electrostatic voltage
levels generated by different activities.

Table 4-1

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

A product can be degraded by as little as 700 volts.

268135-002.book Page 7 Thursday, October 24, 2002 4:10 PM