Installation Manual
Quidway S5000 Series Ethernet Switches
Chapter 2 Installation Preparation
Huawei Technologies Proprietary
2-2
Meanwhile, the electrostatic is likely to be produced in the dry environment, which will
jeopardize the CMOS circuit of the switch. The higher the temperature, the greater the
damage it will do to the Switch. Long-lasting high temperature will speed up the aging
process of the insulating materials, greatly lower the reliability of the switch, and
therefore affect its service life seriously.
2.2.2 Cleanness Requirements
Dust is a hazard to the operating safety of the Switch. The indoor dust accumulated on
the chassis can cause electrostatic adsorption, which may result in the poor contact of
the connector or metal contact point. This happens more frequently when indoor
relative humidity is low, which will not only shorten the service life of the switch, but also
cause communication failure.
The required specifications on dust content and particle diameter in an equipment room
are shown in the following table.
Table 2-1
Limit on dust content in equipment room
Mechanical active
material
Unit
Content
Dust particle
particle/m³
≤
3 x 10
4
(No visible dust on desk in three
days)
Note: Dust particle Diameter
≥
5µm
Besides the dust specifications, the equipment room of the Switch should also meet the
rigorous requirements for the content of salt, acid and sulfide. These harmful gases
could accelerate the metal erosion and the aging process of some parts. Incursion of
harmful gases, such as SO
2
, H
2
S, NO
2
, NH
3
, and Cl
2
, should be prevented. The specific
limitation values of these harmful gases are given in the following table.
Table 2-2
Harmful gas limits in an equipment room
Gas
Max. (mg/m³)
SO
2
0.2
H
2
S
0.006
NH
3
0.05
Cl
2
0.01
2.2.3 Anti-interference Requirements
Any possible interference sources, no matter outside or inside the system, affect the
Switch in use in a way of capacitance coupling, inductance coupling, radiation of
