IBM 8265, Руководство по подготовке площадки

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IBM 8265: Planning and Site Preparation Guide
Maximum Attenuation Standards for UTP/FTP
Table 27 gives, for Category 3, Category 4, and Category 5 cable, the maximum
attenuation values for 305 m (1000 ft) of cable.
The attenuation values for frequencies of 0.512 MHz and below are provided for
information only. These values are intended for engineering design purposes and are
not required for conformance wiring.
The maximum attenuation in Table 27 should be adjusted at elevated temperatures by
using a factor of 0.3% increase per °C for Category 4 and Category 5 cable. Cable
attenuation should be verified at temperatures of 40° C (104 F) and 60° C (140 F) to
determine that the requirements of the above table are met, after adjusting for
temperature.
Table 27. Maximum Attenuation in Horizontal UTP/FTP Cables
Frequency Category 3 Category 4 Category 5
(MHz) UTP
100 ohm
FTP
120 ohm
UTP
100 ohm
FTP
120 ohm
0.064 2.8 2.3 — 2.2 —
0.256 4 3.4 — 3.2 —
0.512 5.6 4.6 — 4.5 —
0.772 6.8 5.7 — 5.5 —
1 7.8 6.5 — 6.3 —
4 17 13 — 13 —
8 26 19 — 18 —
10 30 22 20.4 20 15.9
16 40 27 24.7 25 19
20 — 31 28 28 21.4
25 — — — 32 —
32.25 — — — 36 —
62.5 — — — 52 —
100 — — — 67 67