Dear Rob,
This is a big question and we'll try to cover as many of the variances as possible. For further information you should consult the Telecommunications Building Wiring Standards which includes TIA/EIA-568-B, the revision to 568-A.
First lets start with the Horizontal which has a maximum Link distance of 90 meters regardless of media type. This distance is reduced if a MUTOA is used (see table 6.1 in the standards). For the channel the max distance is 100 meters.
"The length of the cross-connect jumpers and patch cords in the cross-connect facilities, including
horizontal cross-connects, jumpers, and patch cords that connect horizontal cabling with equipment or backbone cabling, should not exceed 5 m (16 ft) in length. For each horizontal channel, the total length allowed for cords in the work area plus patch cords or jumpers plus equipment cables or cords in the
telecommunications room shall not exceed 10 m (33 ft), unless a multi-user telecommunications assembly is used (see subclauses 6.4.1.4 and 6.4.1.5).
NOTE – In establishing the maximum distance for each horizontal channel, an
allowance was made for 5 m (16 ft) from the telecommunications outlet/connector to
the work station." The preceeding statement is from section 4.3 of the standards referenced.
For the backbone cabling (intra and inter building cables) the maximum distance for any cable supporting a network type application follows the horizontal rules of a 90 meter Link and 100 meter Channel.
For other types of recognized media please see figure 5-2 in the standards but here are the numbers from the MC (Main Cross connet) to the HC (horizontal cross connetc):
100 ohn twp - 800 meters
62.5/125 fiber - 2000 meters
50/125 fiber - 200 meters
Singlemode fiber - 3000 meters
If you have an IC (Intermediate cross-connect) the max distances from the MC to the IC are 300 meters for all cable types listed above and the remainder of the MC to HC distance minus the MC to IC distance is the maximum from the IC to the HC.
Hope this helps you
Sincerely,
Joseph Golan, RCDD
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