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APPENDIX A: Twisted-Pair Cable Pinning/Pairing
Appendix A:
Twisted-Pair Cable Pinning/Pairing
The twisted-pair cable you will use to interconnect the Remote and Local in your
ServSwitch™ Brand CAT5 KVM Extender system should be terminated with RJ-45
plugs and should be wired according to the EIA/TIA-568 standard (preferably
568B rather than 568A). See the users’ manual of your Extender system for a more
complete set of cable recommendations.
Looking into the interconnect socket on either Extender unit, or looking at the
cable plug from behind, Pin 1 should be on the left and Pin 8 on the right, and the
wires should be arranged this way:
Pin
Color
Function, Pair
1
White/Orange
TX, Pair 2
2
Orange/White
RX, Pair 2
3
White/Green
TX, Pair 3
4
Blue/White
RX, Pair 1
5
White/Blue
TX, Pair 1
6
Green/White
RX, Pair 3
7
White/Brown
TX, Pair 4
8
Brown/White
RX, Pair 4
NOTES
In runs of our EHN840 cable over 200 m (655 ft.) long, you might get
much better video quality if, at both ends of the cable, you swap the
green and brown pairs so that White/Green is on Pin 7, Green/White on
Pin 8, White/Brown on Pin 3, and Brown/White on Pin 6.
The Extender has been tested with all major makes of CAT5 cable
including Black Box, Berk-Tek™, Mohawk
®
, and AT&T
®
. The Extender
has also been tested and found to work,
in certain situations
, with 4-pair
Category 3 cable or with four pairs of 25-pair UTP trunk cables instead
of 4-pair Category 5 cable. But we do
not
recommend such installations;
if you want to experiment with them, do so at your own risk.
We don’t normally recommend using CAT5e cable (rated for up to
155 Mbps) for runs longer than 100 m (330 ft.), although our EYN795MS
cable has performed well in testing in runs up to the full 300 m (1000 ft.).
Avoid
using cables rated “Level 6,” “Level 7,” etc. If you have problems
getting a good picture with CAT5e cable, or if you
must
use cables with
bandwidths higher than 155 Mbps, please contact tech support; the
signal-skew problems caused by tightly twisted pairs in these cables can
sometimes be resolved by swapping which pairs are used for which signals
or by using an external delay line.
