Preventing Radio Frequency Interference (RFI)
If you use UTP cabling in an installation, take precautions to avoid radio frequency (RF) interference.
RF interference can cause degradation of signal quality, and, in an Ethernet network environment, can
cause excessive collisions, loss of link status, or other physical layer problems that can lead to poor
performance or loss of communication.
To prevent RF interference, avoid the following situations:
•
Attaching UTP cable to AC power cables
•
Routing UTP cable near antennas, such as a ham radio antenna
•
Routing UTP cable near equipment that could exhibit RF interference, such as ARC welding
equipment
•
Routing UTP cable near electrical motors that contain coils
•
Routing UTP cable near air conditioner units
•
Routing UTP cable near electrical transformers
In areas or applications where these situations cannot be avoided, use fiber optic cabling or shielded
twisted pair cabling.
Meeting Power Requirements
Observe the following requirements and precautions for powering your hardware.
Power Supply Requirements
Follow these recommendations when you plan power supply connections for your equipment:
•
Place the equipment in an area that accommodates the power consumption and component heat
dissipation specifications.
•
Be sure that your power supply meets the site DC power or AC power requirements of the network
equipment.
•
When you connect power to installed equipment, do not make this connection through an extension
cord or power strip.
•
If your switch includes more than one power supply, connect each power supply to a different,
independent power source.
If a power source fails, it will affect only the switch power supply to which it is connected. If all switch
power supplies are connected to a single power source, the entire switch is vulnerable to a power
source failure.
•
In regions that are susceptible to electrical storms, we recommend that you plug your system into a
surge suppressor.
For detailed power specifications for your equipment, see "Technical Specifications."
Requirements for Power Cords
Most ExtremeSwitching switches do not ship with power cords. Visit
for information on selecting and purchasing the correct power cords for use with
Preparing to Install
ExtremeAccess Series: Hardware Installation Guide
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