•
Rack-mounting
Temperature and humidity
You must maintain a proper temperature and humidity in the equipment room. Long-term high humidity
may lead to bad insulation, electricity leakage, mechanical property changes, and metal corrosion.
However, if the relative humidity is too low, captive screws may become loose as the result of contraction
of insulation washers and static electricity may be produced in a dry environment to jeopardize the
circuits on the device. A high temperature is the most undesirable condition, because it accelerates the
aging of insulation materials and significantly lowers reliability and service life of the router.
For the temperature and humidity requirements of the router, see
Table 1
.
Table 1
Temperature/humidity requirements
Temperature Relative
humidity
0°C to 40°C (32°F to 104°F)
5% to 90%
Cleanness
Dust buildup on the chassis may 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 2
Dust concentration limit in the equipment room
Substance
Concentration limit (particles/cu m)
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 3
.
Table 3
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
Cooling system
•
Make sure there is enough space (greater than 10 cm (3.94 in)) around the air intake and outlet
vents on the router for good ventilation.
•
Make sure the installation site has a good cooling system.
9
