Humidity - H3C S7500X Series Installation Manual

Humidity

Maintain appropriate humidity in your equipment room, as described in
•
Lasting high relative humidity can cause poor insulation, electricity leakage, mechanical
property change of materials, and metal corrosion.
•
Lasting low relative humidity can cause washer contraction and ESD and bring problems
including loose mounting screws and circuit failure.
Table 2 Humidity requirements
Humidity
Operating humidity (noncondensing)
Storage humidity (noncondensing)
Cleanliness
Mechanically active substances buildup on the chassis might result in electrostatic adsorption, which
causes poor contact of metal components and contact points. In the worst case, electrostatic
adsorption can cause communication failure.
Table 3 Mechanically active substance concentration limit in the equipment room
Substance
Dust particles
Dust (suspension)
Dust
(sedimentation)
Sand
The equipment room must also meet strict limits on salts, acids, and sulfides to eliminate corrosion
and premature aging of components, as shown in
Table 4 Harmful gas limits in the equipment room
Gas
SO
2
H S
2
NH
3
Cl
2
NO
2
EMI
All electromagnetic interference (EMI) sources, from outside or inside of the switch and application
system, adversely affect the switch in the following ways:
•
A conduction pattern of capacitance coupling.
Particle diameter
≥ 5 µm
≤ 75 µm
75 µm to 150 µm
≥ 150 µm
Maximum concentration (mg/m
0.2
0.006
0.05
0.01
0.04
Range
5% RH to 95% RH
5% RH to 95% RH
Concentration limit
4
≤ 3 x 10 particles/m
(No visible dust on desk in three days)
3
≤ 0.2 mg/m
2
≤ 1.5 mg/(m h)
3
≤ 30 mg/m
Table 4.
3
Table 2.
3
3
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