Cisco 2651XM-V, Руководство по установке оборудования

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Chapter 3 Switch Installation
Preparing for Installation
3-6
Catalyst 3750 Switch Hardware Installation Guide
78-15136-02
Installation Guidelines
When determining where to place the switch, be sure to observe these
requirements:
• For 10/100 and 10/100/1000 ports, cable lengths from the switch to connected
devices are up to 328 feet (100 meters).
•
Copper 1000BASE-T SFP modules use standard four twisted-pair, Category
5 cable at lengths up to 328 feet (100 meters).
•
Table 3-1 lists the cable specifications for 1000BASE-SX and
1000BASE-LX fiber-optic SFP connections. Each port must match the
wave-length specifications on the other end of the cable, and the cable must
not exceed the stipulated cable length for reliable communications.
• Operating environment is within the ranges listed in Appendix A, “Technical
Specifications.”
•
Clearance to front and rear panels is such that
–
Front-panel indicators can be easily read.
–
Access to ports is sufficient for unrestricted cabling.
Table 3-1 Fiber-Optic SFP Module Port Cabling Specifications
SFP Module
Wavelength
(nanometers)
Fiber Type
Core Size
(micron)
Modal
Bandwidth
(MHz/km)
Cable Distance
1000BASE-SX 850 MMF 62.5
62.5
50.0
50.0 160
200
400
500 722 feet (220 m)
902 feet (275 m)
1640 feet (500 m)
1804 feet (550 m)
1000BASE-LX/LH 1300 MMF
1
SMF
1. A mode-conditioning patch cord is required. Using an ordinary patch cord with MMF, 1000BASE-LX/LH SFP modules,
and a short link distance can cause transceiver saturation, resulting in an elevated bit error rate (BER). When using the
LX/LH SFP module with 62.5-micron diameter MMF, you must also install a mode-conditioning patch cord between the
SFP module and the MMF cable on both the sending and receiving ends of the link. The mode-conditioning patch cord is
required for link distances greater than 984 feet (300 m).
62.5
50.0
50.0
9/10 500
400
500
— 1804 feet (550 m)
1804 feet (550 m)
1804 feet (550 m)
32,810 feet (10 km)