Cabletron Systems TRXI-42, TRXI-22 Attenuation and Impedance, Frequency Impedance Attenuation

REQUIREMENTS/SPECIFICATIONS

2.1.1UTP 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		100Ω ±15%	<26 dB/km (8 dB/1000 ft)
4	MHz		100Ω ±15%	<56 dB/km (16 dB/1000 ft)
10		MHz	100Ω ±15%	<98 dB/km (30 dB/1000 ft)
16		MHz	100Ω ±15%	<131 dB/km (40 dB/1000 ft)

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