Black Box LPM600A, Manual

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4. Link Fault Pass Through
This media converter supports link fault pass through (LFP) in TX/FX converter application. Link status on
one port is propagated to the other port to notice the remote nodes. If TP port is unplugged, this converter
stops transmission on fiber port. This causes the remote fiber node link to fail. LED shows the link failure on
both TP and fiber ports. If fiber link fails, this converter restarts auto-negotiation on TP port but always stays in
the link failure state. This causes the remote TP node link to fail. LED also shows the link failure on both TP
and fiber ports. Refer to Figure 4-1 shown below for the normal status when the link succeeds. Also refer to
Figure 4-2 and Figure 4-3 for the erroneous status when TP Cable A, Fiber Cable B or Fiber Cable C fails to
connect.
NOTE
●
indicates LNK/ACT LED Lit
○
indicates LNK/ACT LED Off
Figure 4-1 Normal status via a pair of LFPs
Figure 4-2 The status as TP Cable A is broken
LFP LFP
Ethernet Switch
TP Cable TP Cable
Fiber
Cable
Ethernet Switch Remote Station
B A
C
LFP LFP
Ethernet Switch
TP Cable TP Cable
Fiber
Cable
Ethernet Switch Remote Station
B
C
A
PSE PoE 10/100BASE-TX to 100BASE-FX Media Converter
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