Installation Manual
H3C S9500 Series Routing Switches
Chapter 2 Installation Preparations
2-4
Table 2-2
Humidity requirements
Humidity
Range
Operating humidity (noncondensing)
10% to 90%
Storage humidity (noncondensing)
5% to 95%
Long-lasting high humidity in the equipment room is prone to poor insulation or even
leakage of the insulating material. Sometimes, the mechanical performance
deterioration, the rustiness and corrosion of some metal parts are also more likely to
occur.
If the relative humidity is too low, the captive screws may become loose due to the
insulation washer contraction. Meanwhile, the electrostatic is likely to be produced in
the dry environment, which will jeopardize the CMOS circuit of the switch.
2.2.3 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 2-3
Limitation on dust content in equipment room
Mechanical active material
Unit
Content
Dust particle
particles/m³
≤
3 x 10
4
(No visible dust on desk in
three days)
Note: Dust particle diameter
≥
5 µm
Besides the dust specifications, the equipment room of the switch should also meet the
rigorous requirements for the content of salt, acid and sulfide in the air. 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.
