Instruction manual

5
Twisted Pair Crossover/Straight-Through Connections
Whether using crossover or straight-through CAT5 twisted pair cabling, all Switching
Modules will support both types of connections by one of the following methods:
AutoCross McLIM TX/FX (-00) and McGigabit include AutoCross, a feature that
automatically selects between a crossover workstation or straight-through
connection depending on the connected device.
MDI-II/MDI-X
Switch
All McPIMs feature a 2-position switch, located at position S1 (see table for
location on boards), for selecting a crossover workstation connection or
straight-through connection.
The switch is labeled with “X” for a crossover connection (factory default)
and an “ll” for a straight-through connection. Select the appropriate
setting by moving the switch to the proper position before installing the
media conversion module. If uncertain whether crossover or straight-
through is needed, set the switch to the position that makes the link LED
glow.
Device-
Dependent
The end device connected to the McLIM TX/FX and TX/SX (-50)
determines the type of twisted pair connection: this McLIM does include
AutoCross or a MDI-II/MDI-X switch.
Twisted Pair Cable Distance
Some McPIM TP/FOs features a 2-position jumper, located at position JP2, for
selecting longer twisted pair cable distances (distances greater than 100 meters).
Place the jumper over both pins for distances up to 100 meters (factory default).
Remove the jumper shunt or place it on only one pin for distances of 100 meters or
more.
NOTE
The product on the other side of the conversion must be able to support longer cable
distances.
Twisted Pair Cable Type
Some McPIM TP/FOs (-20 and -40) features a 2-position jumper, located at position
JP3, for selecting either a shielded or unshielded twisted pair link segment. Remove
the jumper shunt or place it on only one pin to select an unshielded twisted pair link
segment (factory default). Place the jumper shunt over both pins to select a shielded
twisted pair link segment.