Cisco Systems 511 User Manual

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Cisco Content Engine 511 and 566 Hardware Installation Guide
OL-5756-01
Chapter 6      Maintaining the Content Engine
    Maintaining Your Site Environment
Humidity
High-humidity conditions can cause moisture migration and penetration into the 
system. This moisture can cause corrosion of internal components and 
degradation of properties such as electrical resistance, thermal conductivity, 
physical strength, and size. Extreme moisture buildup inside the system can result 
in electrical shorts, which can cause serious damage to the system.
Each system is rated to operate at 8 to 80 percent relative humidity, with a 
humidity gradation of 10 percent per hour. Buildings in which climate is 
controlled by air conditioning in the warmer months and by heat during the colder 
months usually maintain an acceptable level of humidity for system equipment. 
However, if a system is located in an unusually humid location, a dehumidifier can 
be used to maintain the humidity within an acceptable range.
Altitude
Operating a system at high altitude (low pressure) reduces the efficiency of forced 
and convection cooling and can result in electrical problems related to arcing and 
corona effects. This condition can also cause sealed components with internal 
pressure, such as electrolytic capacitors, to fail or perform at reduced efficiency.
Each system is rated to operate at a maximum altitude of 6998 feet (2133 meters) 
and can be stored at a maximum altitude of 15,000 feet (4570 meters).
Dust and Particles
A clean operating environment can greatly reduce the negative effects of dust and 
other particles, which act as insulators and interfere with the operation of a 
system’s mechanical components. Also, in addition to regular cleaning, you 
should follow these guidelines to deter contamination of the system equipment:
Do not permit smoking anywhere near the system.
Do not permit food or drink near the system.
Use dust covers when the system is not in use.
Close windows and outside doors to keep out airborne particles.