H3C Technologies H3C S9500 Series Switches - Manual (Page 66)

Installation Manual
H3C S9500 Series Routing Switches
Chapter 3 Installation Preparation
3-4
Table 3-1 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 ≥ 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 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.
Table 3-2 Harmful gas limits in an equipment room
Gas Average (mg/m
3
) Max. (mg/m
3
)
SO
2
0.3 1.0
H
2
S 0.1 0.5
NO
2
0.004 0.15
NH
3
1.0 3
Cl
2
0.1 0.3
3.2.3 Anti-Static Requirements
Any possible interference sources, no matter outside or inside the system, affect the
switch in use in a way of capacitive coupling, inductive coupling, electromagnetic
radiation, common impedance (including the grounding system) coupling or conducting
line (power line, signaling line and transmission line etc). To prevent the interference,
you should:
z
Take effective measures against electrical net interference for power supply
system.
z
Separate the working ground of the switch from the grounding device of the power
supply equipment or lightning-protection grounding device as far as possible.
z
Keep the switch far away from the radio launcher, radar launcher, and
high-frequency devices working in the high current.
z
Adopt electromagnetic shielding if necessary.