Cabletron Systems TRXI-42 User Manual

Page of 92
 
REQUIREMENTS/SPECIFICATIONS
 
Page 2-2
 
2.1.1
UTP Cable Specifications for the TRXI-22/24 Lobe Ports
and TPIM-T2
 
The TRXI-22 and TRXI-24 lobe ports and the TPIM-T2 support voice 
grade Unshielded Twisted Pair (UTP) cable, as described in EIA/TIA 
TSB 568, and IBM Type 3 cable.
UTP consists of four pairs of 24 AWG solid wire for data or voice 
communication and is typically used to wire cable runs within the 
walls of buildings. In some installations, existing UTP building wiring 
can be used for token ring cabling. UTP cable must conform to the 
limits shown in Table 2-1.
 
Warning
 
: DO NOT
 
 
 
connect UTP cabling to any non-token ring network 
conductors (telephone, etc.) or ground. If in doubt, test wiring before 
using. Telephone Battery and Ringing voltages, used in UTP telephone 
circuits, could present a shock hazard and can damage token ring 
equipment when connected to token ring cabling.
 
The increased popularity and cost advantages of UTP cable have 
driven refinements to UTP cable design. As a result, better grades of 
UTP cable, known as supergrade or level 4, are available that exhibit 
improved transmission characteristics. These improved grades of UTP 
can often be used to permit operation at 16 Mbps on longer lobe cables.
 
Attenuation and Impedance
 
The values listed in Table 2-1 include the maximum attenuation of the 
cables, connectors, patch panels, and reflection losses due to 
impedance mismatches in the segment. 
Table 2-1. UTP Voice Grade and Category 3 Specifications
 
Frequency
Impedance
Attenuation
 
1 MHz
100
 
Ω
 
 
 
±
 
15%
<26 dB/km (8 dB/1000 ft)
4 MHz
100
 
Ω
 
 
 
±
 
15%
<56 dB/km (16 dB/1000 ft)
10 MHz
100
 
Ω
 
 
 
±
 
15%
<98 dB/km (30 dB/1000 ft)
16 MHz
100
 
Ω
 
 
 
±
 
15%
<131 dB/km (40 dB/1000 ft)