User`s guide

A-9
9H423-26 Cabling Requirements
Return Loss (SRL). Refer to Table A-4. To be labeled as Category 5, the following
SRL values must be satisfied.
• Attenuation - Attenuation refers to the amount of signal level degradation
through a medium. This can be caused from impurities in the cable, and
therefore the signal will not propagate as far. The following table lists the
maximum attenuation (dB) per cable pair at 20° C. Refer to Table A-5.
Table A-4. UTP Cable SRL
Freq. f (MHz) CAT 3 (dB) CAT 4 (dB) CAT 5 (dB)
1-10 12 21 23
10-16 12log(f/10) 21-10log(f/10) 23
16-20 - 21-10log(f/10) 23
20-100 - - 23-10log(f/20)
Table A-5. Cable Attenuation per 100 m
Freq (MHz) CAT 3 (dB) CAT 4 (dB) CAT 5 (dB)
0.064 0.9 0.8 0.8
0.256 1.3 1.1 1.1
0.512 1.8 1.5 1.5
0.772 2.2 1.9 1.8
1 2.6 2.2 2.0
4 5.6 4.3 4.1
8 8.5 6.2 5.8
10 9.7 6.9 6.5
16 13.1 8.9 8.2
20 - 10.0 9.3
25 - - 10.4
31.25 - - 11.7
62.5 - - 17.0
100 - - 22.0