Installation Guide for the Model FS508 Fast Ethernet Switch
C-2
Cabling Guidelines
Cable Lengths
Category 5 distributed cable that meets ANSI/EIA/TIA-568-A building wiring standards can be
a maximum of 328 feet (100 meters) in length, divided as follows:
•
20 feet (6 meters) between the hub and the patch panel (if used)
•
295 feet (90 meters) from the wiring closet to the wall outlet
•
10 feet (3 meters) from the wall outlet to the desktop device
The patch panel and other connecting hardware must meet the requirements for 100 Mbps
operation (Category 5). Only 0.5 inch (1.5 cm) of untwist in the wire pair is allowed at any
termination point.
Cable Specifications
Table 5-1
lists the electrical requirements of Category 5 cable.
Table 5-1.
Electrical requirements of Category 5 cable
Specification
Category 5
Number of pairs
Four
Impedance
100
Ω
±
15%
Mutual capacitance at 1 KHz
≤
5.6 nF per 100 m
Maximum attenuation (dB per 100 m, at 20
°
C)
at 4 MHz: 8.2
at 31 MHz: 11.7
at 100 MHz: 22.0
NEXT loss (dB minimum)
at 16 MHz: 44
at 31 MHz: 39
at 100 MHz: 32
FS508.BK Page 2 Wednesday, May 7, 1997 10:29 AM
