Electromagnetic And Radio Frequency Interference; Magnetism - Cisco WAE-674-K9 - Wide Area Application Engine 674 Hardware Installation Manual

Appendix B Maintaining the Wide Area Application Engine

Electromagnetic and Radio Frequency Interference

Magnetism

OL-15012-02
Wear a grounding wrist strap. If a grounding wrist strap is unavailable, touch
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an unpainted metal surface on the chassis periodically to neutralize any static
charge.
Keep components in their antistatic packaging until they are installed.
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Avoid wearing clothing made of wool or synthetic materials.
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Electromagnetic 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's
monitor screen.
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 like 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:
Operate the system only with the system cover installed.
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Ensure that the screws on all peripheral cable connectors are securely
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fastened to their corresponding connectors on the back of the system.
Always use shielded cables with metal connector shells for attaching
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peripherals to the system.
Because they store data magnetically, hard disk drives are extremely susceptible
to the effects of magnetism. Hard disk drives should never be stored near magnetic
sources such as the following:
Monitors
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TV sets
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Cisco Wide Area Application Engine 7341, 7371, and 674 Hardware Installation Guide
Maintaining Your Site Environment
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