Cisco Catalyst 6816-X-LE, Руководство по установке оборудования

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• The color coding of the source DC power cable leads depends on the color coding of the site DC power
source. Typically, green or green and yellow indicate that the cable is a ground cable. Because there is
no color code standard for source DC wiring, you must ensure that the power cables are connected to
the DC-input power supply terminal block in the proper (+) and (–) polarity. In some cases, the source
DC cable leads might have a positive (+) or a negative (–) label. This label is a relatively safe indication
of the polarity, but you must verify the polarity by measuring the voltage between the DC cable leads.
When making the measurement, the positive (+) lead and the negative (–) lead must always match the
(+) and (–) labels on the DC-input power supply.
• The circuit breaker is considered to be the disconnect device and should be easily accessible.
• The circuit must be protected by a dedicated two-pole circuit breaker. The circuit breaker should be sized
according to the power supply input rating and local or national code requirements.
• For proper DC-input redundant power configurations on systems with multiple-input DC-input power
supplies, all pairs of source DC cables for one DC-input power supply must come from the same battery
system (A feed); all pairs of source DC cables for the second DC-input power supply must come from
a different battery system (B feed).
• For DC-input power supplies with multiple inputs, each DC input must be protected by a dedicated circuit
breaker or a fuse. The circuit breaker or the fuse must be sized according to the power supply input rating
and local or national electrical codes.
Cabling Requirements
When running power and data cables together in overhead cable trays or subfloor cable trays, be aware of the
following caution:
We strongly recommend that power cabling runs and other potential noise sources be located as far away as
practical from LAN cabling that terminates on Cisco equipment. In situations where this type of long parallel
cable runs exist and cannot be separated by at least 3.3 feet (1 meter), we recommend that you shield these
potential noise sources. To avoid interference, the source should be shielded by housing it in a grounded
metallic conduit.
Caution
Also be aware of the following caution concerning the use of Category 5e and Category 6 Ethernet cables:
Category 5e, Category 6, and Category 6a cables can store large levels of static electricity because of the
dielectric properties of the materials used in their construction. Always ground the cables (especially in new
cable runs) to a suitable and safe earth ground before connecting them to the module.
Caution
Site Preparation Checklist
The following table lists the site-planning activities that you should perform prior to installing the switch.
Completing each activity helps ensure a successful switch installation.
Catalyst 6840-X Switch Series Hardware Installation Guide
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Preparing for Installation
Cabling Requirements