HP V4275EA, V4201XX, V4200, V4000T Typical Electrostatic Voltage Levels, Static-Shielding Materials

Models: V4333EA V4387EA V4332EA V4233TU V4200 V4332US V4320EA V4232TU V4325US V4212TU V4219TU V4354EA V4209TU V4220TU V4217EA V4218TU V4230TU V4322EA V4201XX V4376EA V4310NR V4245US V4000T V4382EA V4227TU V4335EA V4217TU V4275EA V4203XX V4377EA V4222TU V4223TU V4214TU

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Removal and Replacement Preliminaries

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 V.

Table 4-2 lists the shielding protection provided by antistatic bags and floor mats.

Table 4-2

Static-Shielding Materials

Material

Use

Voltage Protection Level

 

 

 

Antistatic plastic

Bags

1,500 V

 

 

 

Carbon-loaded plastic

Floor mats

7,500 V

 

 

 

Metallized laminate

Floor mats

5,000 V

 

 

 

4–8

Maintenance and Service Guide

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HP V4275EA, V4201XX Typical Electrostatic Voltage Levels, Static-Shielding Materials, Relative Humidity Event 10% 40% 55%