3
Table 1
Temperature requirements
Temperature Range
Operating temperature
0°C to 45°C (32°F to 113°F)
Storage temperature
–40°C to +70°C (–40°F to +158°F)
Humidity
Maintain appropriate humidity in your equipment room, as described in
•
Lasting high relative humidity tends to cause poor insulation, electricity creepage, mechanical
property change of materials, and corrosion of metal parts.
•
Lasting low relative humidity is likely to result in loose screws due to washer contraction, and even
electrostatic discharge (ESD), which causes the circuits to fail.
Table 2
Humidity requirements
Humidity Range
Operating humidity
10% to 95%, noncondensing
Storage humidity
5% to 95%, noncondensing
Cleanness
Dust 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
Dust concentration limit in the equipment room
Substance
Concentration limit (particles/m
3
)
Dust particles
≤
3 x 10
4
(No visible dust on desk in three days)
NOTE:
Dust particle diameter
≥
5
μ
m
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 an equipment room
Gas Max.
(mg/m
3
)
SO
2
0.2
H
2
S 0.006
NH
3
0.05
Cl
2
0.01
