REQUIREMENTS/SPECIFICATIONS
Page 2-3
Drive Distance - Drive distance is the limit of reliable signal
propagation without the installation of repeaters in the ring. The
maximum drive distance using Type 1 STP cabling is 770 meters
(2525 feet) at 4 Mbit/sec and 346 meters (1138 feet) at 16 Mbit/sec.
These limits include the combined length of all trunk cables plus
twice the length of the longest lobe cable. (When UTP lobe cables are
used, as with the TRMIM-20R, determining the overall drive distance
requires converting the UTP cable lengths to their Type 1 equivalent
length and then using the Type 1 equivalent to calculate cable
lengths.)
Table 2-1. IBM Cable Types
Type 1
Two shielded twisted pairs (STP) of 22 AWG solid wire
for data. Used for the longest cable runs within the
walls of buildings.
Type 2
Similar to Type 1 data cable, but having four additional
unshielded twisted pairs of 22 AWG solid wire carried
outside of the shield casing. Typically used for voice
communication.
Type 3
Four unshielded twisted pairs (UTP) of 24 AWG solid
wire for data or voice communication. Used for cable
runs in walls of buildings.
Type 5
Two 100/140
µ
m optical fibers in a single sheath.
Type 6
Two STP of 26 AWG stranded wire for data. This type
is used in patch panels or to connect devices to/from
wall jacks.
Type 8
One flat STP of 26 AWG stranded wire for under carpet
installation.
Type 9
Similar to Type 1, but uses 26 AWG solid wire.
NOTES:
1. Refer to Appendix C for cable conversion factors.
2. Table 2-1 lists all cable types for reference. The TRMIM-20R
supports Type 3 for TCU port cabling and Types 1, 2, 6, and 9 as
trunk cabling.