H3C CR19000-16, Руководство по установке

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1-4
Temperature and humidity
CAUTION:
If condensation occurs on the chassis when you move it from a lower temperature to a higher
temperature, dry the chassis before powering it on to avoid short circuits.
If the temperature in the equipment room is too high, too low, or changes dramatically, the device
reliability is reduced and its service lifetime is shortened. For long-term, highly available operation of
the router, make sure temperature and humidity in the equipment room meets the requirements
described in
Table1-2 .
•
High temperature can accelerate the aging of insulation materials and significantly lower the
reliability and lifespan of the router.
•
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 screws and circuit failure.
Table1-2 Temperature and humidity requirements
Item Operating Storage
Temperature 0°C to 45°C (32°F to 113°F) –40°C to +70°C (–40°F to +158°F)
Humidity 5% RH to 95% RH, noncondensing 5% RH to 95% RH, 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.
Table1-3 Mechanically active substance concentration limit in the equipment room
Substance Particle diameter Concentration limit
Dust particles
≥ 5 µm
≤ 3 × 10 4
particles/m
3
(No visible dust on desk in three days)
Dust (suspension)
≤ 75 µm ≤ 0.2 mg/m 3
Dust
(sedimentation)
75 µm to 150 µm
≤ 1.5 mg/(m 2
h)
Sand 150 µm to 1000 µm
≤ 30 mg/m 3
To maintain cleanliness in the equipment room, follow these guidelines:
•
Use dustproof materials for floors and walls and use coating that does not produce powders.
•
Use double-layer glass in windows and seal doors and windows with dust-proof rubber strips.
Use screen doors and screen windows in the external side.
•
Keep the equipment room clean and clean the air filters of the rack regularly.
•
Wear ESD clothing and shoe covers before entering the equipment room.