H3C Technologies H3C S12500 Series Switches - Manual (Page 14)

4
Maintain appropriate humidity in your equipment room, as described in Table 2 .
Table 2 Humidity requirements
Item Specifications
Operating humidity (noncondensing) 5% to 95%
Storage humidity (noncondensing) 5% to 95%
Operating altitude
Table 3 Operating altitude requirements
Item Specifications
Operating altitude
≤ 4000 m (13123.36 ft) (available altitude)
≤ 3000 m (9842.52 ft) (certificated altitude)
Cleanness
Dust buildup on the chassis might result in electrostatic adsorption, which causes poor contact of metal
components and contact points, especially when indoor relative humidity is low. In the worst case,
electrostatic adsorption can cause communication failure.
Table 4 Dust concentration limit in the equipment room
Substance Concentration limit (particles/m 3 )
Dust particles ≤ 3 x 10 4 (no visible dust on the tabletop over three days)
NOTE:
Dust particle diameter ≥ 5 μm
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 5 .
Table 5 Harmful gas limits in the 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
EMI
All electromagnetic interference (EMI) sources, from outside or inside of the switch and application
system, adversely affect the switch in a conduction pattern of capacitance coupling, inductance coupling,