Triplett TVR10/100/1000 - Manual (Page 34)

(see Appendix A). See note below for required pairs.
INVERTED PAIRS: If any of the pairs are present but have incorrect
polarity (i.e. the “1,2” pair is really “2,1”) the pair’s LED will light red.
Inverted pairs can slow down or stop a link.
PAIR NOT PRESENT: The LEDs will not light, if the pair does not
exist or if the pair is shorted across itself.
STRAIGHT THRU OR CROSSOVER: If the LEDs light in a
top-down order, the cable is wired in a straight thru configuration
(e.g. “1,2” to “3,6” to “4,5” to “7,8” indicates a straight thru cable
connection. If the LEDs light in a bottom-up order, the cable is wired
crossover configuration (e.g. “7,8” to “4,5” to “3,6” to “1,2”) indicates
a crossover cable). LEDs not lighting in order indicates pairs may
be swapped.
SHORTED PAIRS: If a pair is shorted across itself, it will show up
as a non existent pair (LED will be OFF). If the short is across pairs
it will either light one pair red and the other green (simultaneously)
or an individual LED will alternate red and green. Summary: Any
red color indicates a wiring problem.
Notes: If pairs “1,2” and “3,6” are not both present, there is no
possibility of communication. If pairs “4,5” or “7,8” are not present,
data rates maybe impaired (some 100 MB/s systems and all 1000
MB/s require 4 pairs). The Remote Probe will not interfere with an
active LAN.
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