Lobe Cabling Requirements; Stp Lobe Cables; Stp Network Cable Specifications - 3Com CoreBuilder 5000 User Manual

Table 2-3
Ring Speed
Active (A)/
Passive (P)
4 Mbps
16 Mbps
* With the exception of the 190 stations, which should be reduced if there are more than
25 stations with lobe lengths approaching 800 meters.
Lobe Cabling The section describes recommended twisted pair lobe cable
Requirements requirements for the following cable types:

STP Lobe Cables

UTP/Levels 3, 4, and 5 Lobe Cables
120 ohm (Screened Twisted Pair) Lobe Cables
STP Lobe Cables
Use STP cable that meets the requirements defined in SP-2840:
Commercial Building Telecommunications Cabling Standard
(ANSI/TIA/EIA).
To maintain the performance of a robust network design, use wiring
that meets or exceeds the specifications defined in
Table 2-4
Characteristic
Impedance
Attenuation (dB/100 m)
Crosstalk (dB maximum)
The attenuation listed in
25° Celsius. The use of cables in an environment with temperatures
higher than 25° Celsius may result in decreased distances. Refer to the
Planning and Installation Guide for Customer Premises Cabling to
Support Attachment of ISO 8802-5 Token Ring Stations for more
details.
Selecting Appropriate Cable Lengths
Maximum Lobe Lengths (in Meters)
STP UTP Level 5
A P A
*
800 400 425
400 200 225

STP Network Cable Specifications

4 Mbps
135 to 165 ohm
2.2 dB
–58 dB
Table 2-4
UTP Level 4
P A P
200 425 200
100 210 100
Table
16 Mbps
135 to165 ohm
4.5 dB
– 40 dB
applies to cables at a temperature of
2-7
UTP Level 3
A P
250 125
100 N/A
2-4.