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6.1. The
Cable Sniffer-Remote
indicates the
cable is not working, but my LAN
works OK:
Installed LAN cables with RJ-45 connectors
that have been in service and working OK
may test as Open, Shorted, or Crossed.
Here’s why---The EIA/TIA 568 standard for
LAN cable only uses 4 of the wires in the
eight-wire cable. The other 4 wires in the
cable may have faults, but these will not affect
the operation of the LAN. The 4 in 1 tests all
of the wires in the LAN cable, and identifies
the faults, even though these wires may not
being used in the LAN system. Not all LAN
cables are wired straight through Crossover
cables used on LANs are purposely mis-wired,
with their Receive and Transmit wires cross
over. The CABLE SNIFFER-REMOTE will
test this as a bad cable, but it may work just
fine as Crossover cable.
6.2.
The
CABLE SNIFFER-REMOTE
says
my cable is good, but it does not
work on my LAN:
Many cable testers like the CABLE
SNIFFER-REMOTE only perform continuity
style tests (open, short, crossover, etc).
Ethernet LAN cables are constructed in a
special way. The 8 wires inside are grouped
into 4 pairs of 2 way. Not only must the 8
wires connect from end to end of the cable,
the pairs in the cable must connect to specific
pins of RJ-45 plugs on to the ends of cable
ignoring the pairing (as described in EIA/TIA
568),and the cable will test ok. But when the
