CABLING GUIDELINES
Fast Ethernet Cable Guidelines
Fast Ethernet uses UTP cable, as specified in the IEEE 802.3u standard for
When installing Category 5 UTP cabling, use the following guidelines to ensure that your cables perform to the following specifications:
•Certification
Make sure that your Category 5 UTP cable has completed the Underwriters Laboratories (UL) or Electronic Testing Laboratories (ETL) certification process.
•Termination method
To minimize crosstalk noise, maintain the twist ratio of the cable up to the point of termination; untwist at any
Cable Lengths
Category 5 distributed cable that meets
•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
The following lists he electrical requirements of Category 5 cable.
Specification | Category 5 Cable |
Number of pairs | Four |
Impedance | 100 & ± 15% |
Mutual capacitance at 1 KHz | £ 5.6 nF per 100 m |
Maximum attenuation | at 4 MHz: 8.2 |
(dB per 100 m, at 20° C) | 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 |
www.netcomm.com.au | Rev.1 - YML623 |
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