3
Examining the installation site
The firewall can only be used indoors. To make sure the firewall operates correctly and to prolong its
service lifetime, the installation site must meet the following requirements.
Weight support
Make sure the floor can support the total weight of the rack, chassis, modules, and all other
components. For weights of the chassis and components, see "Appendix A Chassis views and
technical specifications."
Temperature and humidity
Maintain appropriate temperature and humidity in the equipment room.
•
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 captive screws and circuit failure.
•
High temperature can accelerate the aging of insulation materials and significantly lower the
reliability and lifespan of the firewall.
For the temperature and humidity requirements of the firewall, see
Table1-1 Temperature/humidity requirements
Temperature
Relative humidity
•
Operating:
Without drives: 0°C to 45°C (32°F to 113°F)
With drives: 5°C to 40°C (41°F to 104°F)
•
Storage: –40°C to +70°C (–40°F to +158°F)
•
Operating:
Without drives: 5% to 95%, noncondensing
With drives: 10% to 90%, noncondensing
•
Storage: 5% to 95%, noncondensing
Cleanliness
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.
Table1-2 Dust concentration limit in the equipment room
Substance
Concentration limit (particles/m
3
)
Dust particles
≤ 3 × 10
4
(No visible dust on desk in 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
Table1-3 Harmful gas limits in an equipment room
Gas
Max. (mg/m
3
)
SO
2
0.2
