Altitude; Dust And Particles; Corrosion; Emi And Radio Frequency Interference - Cisco Catalyst 6880-X Hardware Installation Manual

Preparing for Installation

Altitude

Operating a system at high altitude (low pressure) reduces the efficiency of forced and convection cooling
and may result in electrical problems related to arcing and corona effects. This condition may also cause sealed
components with internal pressure, such as electrolytic capacitors, to fail or perform at reduced efficiency.
The Catalyst 6880-X switch is rated to operate at altitudes from 0 to 6500 feet (0 to 2000 meters) and can be
stored at altitudes of –200 to 10,000 feet (–60 to 3000 meters).

Dust and Particles

Fans cool power supplies and system components by drawing in room-temperature air and exhausting heated
air out through various openings in the chassis. However, fans also ingest dust and other particles, causing
contaminant buildup in the system and increased internal chassis temperature. A clean operating environment
can greatly reduce the negative effects of dust and other particles, which act as insulators and interfere with
the mechanical components in the system. The standards listed below provide guidelines for acceptable
working environments and acceptable levels of suspended particulate matter:
• National Electrical Manufacturers Association (NEMA) Type 1
• International Electrotechnical Commission (IEC) IP-20

Corrosion

Corrosion of system connectors is a gradual process that may eventually lead to intermittent failures of electrical
circuits. The oil from a person's fingers or prolonged exposure to high temperature or humidity may corrode
the gold-plated edge connectors and pin connectors on various components in the system. To prevent corrosion,
avoid touching contacts on boards and cards, and protect the system from extreme temperatures and moist,
salty environments.

EMI and Radio Frequency Interference

EMI and radio frequency interference (RFI) from a system can adversely affect devices such as radio and
television (TV) receivers operating near the system. Radio frequencies emanating from a system can also
interfere with cordless and low-power telephones. Conversely, RFI from high-power telephones can cause
spurious characters to appear on the system monitor. RFI is defined as any EMI with a frequency above 10
kilohertz (kHz). This type of interference can travel from the system to other devices through the power cable
and power source, or through the air in the form of transmitted radio waves. The Federal Communications
Commission (FCC) publishes specific regulations to limit the amount of EMI and RFI emitted by computing
equipment. Each system meets these FCC regulations. To reduce the possibility of EMI and RFI, follow these
guidelines:
• Always operate the system with the chassis covers installed.
• Ensure that all chassis slots are covered by a metal filler bracket and that an unused power supply bay
• Ensure that the screws on all peripheral cable connectors are securely fastened to their corresponding
OL-30827-02
has a metal cover plate installed.
connectors on the back of the chassis.

Catalyst 6880-X Switch Hardware Installation Guide

Altitude
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