Cisco Nexus 9364E-SG2 Hardware Installation Manual page 13

Preparing the Site
Minimizing Electromagnetic and Radio Frequency Interference
Electromagnetic interference (EMI) and radio frequency interference (RFI) from the switch can adversely
affect other devices, such as radio and television (TV) receivers. Radio frequencies that emanate from the
switch can also interfere with cordless and low-power telephones. Conversely, RFI from high-power telephones
can cause spurious characters to appear on the switch monitor.
RFI is defined as any EMI with a frequency above 10 kHz. This type of interference can travel from the switch
to other devices through the power cable and power source or through the air as transmitted radio waves. The
Federal Communications Commission (FCC) publishes specific regulations to limit the amount of EMI and
RFI that are emitted by computing equipment. Each switch meets these FCC regulations.
To reduce the possibility of EMI and RFI, use these guidelines:
• Cover all open expansion slots with a blank filler plate.
• Always use shielded cables with metal connector shells for attaching peripherals to the switch.
When wires are run for any significant distance in an electromagnetic field, interference can occur to the
signals on the wires with these implications:
• Bad wiring can result in radio interference emanating from the plant wiring.
• Strong EMI, especially when it is caused by lightning or radio transmitters, can destroy the signal drivers
Note
The wiring is unlikely to emit radio interference if you use a twisted-pair cable with a good distribution of
grounding conductors. If you exceed the recommended distances, use a high-quality twisted-pair cable with
one ground conductor for each data signal, when applicable.
Caution
Shock and Vibration Requirements
The switch has been shock- and vibration-tested for operating ranges, handling, and earthquake standards.
and receivers in the chassis and even create an electrical hazard by conducting power surges through
lines into equipment.
To predict and prevent strong EMI, consult experts in radio frequency interference (RFI).
If the wires exceed the recommended distances, or if wires pass between buildings, give special consideration
to the effect of a lightning strike in your vicinity. The electromagnetic pulse that is caused by lightning or
other high-energy phenomena can easily couple enough energy into unshielded conductors to destroy electronic
switches. Consult experts in electrical surge suppression and shielding if you have had similar problems in
the past.
Cisco Nexus 9364E-SG2 (N9364E-SG2-Q) NX-OS-Mode Switch Hardware Installation Guide
Minimizing Electromagnetic and Radio Frequency Interference
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