Static Electricity - Fujitsu M10 Series Installation Planning Manual

5.3

Static Electricity

Static electricity may be charged and kept in a person's body by the following
conditions.
 Through friction between shoes and floor as a result of his or her walking.
 Through friction between clothes and body.
 Also, carts may be charged as a result of their movement.
When this static electricity is discharged to server system at a high charge voltage, it
could cause a malfunction. Hence, take steps to make the computer room less
susceptible to electrostatic generation.
5.3.1 Recommended electrostatic voltage for a computer room
It is best if the static electricity charge on human bodies or carts be kept at such level
or lower that there is no discomfort to the people when there is a discharge. For
example it will not cause pain in the skin at discharge. This is variable from one
individual to another, but it is generally about 2.0 kV (kilovolt). An electrostatic
discharge of 2.0 kV or lower should not affect the server system.
5.3.2 Electrostatic control in the computer room
To inhibit the generation of static electricity, choose flooring that is rarely charged
with static electricity and use humidity control. For computer room flooring surface
materials, see
Section 4.3.3, "Temperature and humidity recommendations for computer rooms."
C120-H007-08EN
Table 2.3 For suggested computer room humidities, see
5.3 Static Electricity
Table 4.1 and
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