Black Box Mixed-Media Fiber Hubs
Installation and User Guide (4/99)
Important Note:
For the LH8056C-UP Crossover Switch -
OUT
for workstations and user connections.
IN
for Up-Link connections to other hubs, etc.
The LH8056C pins normally (TP crossover switch DOWN) are per the standard for hubs-
to-users twisted pair wiring: 1 = , 2 = receive-, 3 = t, 6 = transmit-, other
pins not used. When the TP crossover switch is UP, the pins of the RJ-45 port are per the
standard for up-links using twisted pair wiring, i.e., the transmit and the receive pairs are
exchanged: 1 = t, 2 = transmit-, 3 = , 6 = receive-, other pins not used.
5.2.7 LH8057A-PNL
The LH8057A-PNL is a blank face
plate that must be installed in any empty PM
slot. When the LH8050A chassis contains less
than twelve front-mounted PMs, the empty front
slots must be covered with the LH8057A-PNL
face plate in order to maintain proper cooling air
flow, and for safety, etc.
LH8057A-PNL
Note:
The LH8057A-PNL
must be installed in
each empty PM slot.
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6.0 TROUBLESHOOTING
If problems should develop during installation or operation, follow the
suggestions below prior to calling Technical Support for help. If you are unsure of any
procedure described in this chapter, or if the Dual-Speed Fiber Hub is not operating as
expected, do not attempt to repair or alter the unit. Contact Black Box for assistance.
6.1
Before Calling for Assistance
1.
If you have difficulty installing or operating the Dual-Speed Fiber Hub, refer to
Chapters 3
and
4.
Make sure that the various other components of the network are
working.
2.
Check the cables and connectors to make sure that they have been properly connected
and the cables/wires have not been crimped or in some way impaired during
installation.
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