3Com 3C16683 User Manual page 2

Figure 1 100BASE-TX Distance Extender Module
Important Safety Information
WARNING: Installation and removal of the
Module must be carried out by qualified
personnel only. Before installing the Module
into a hub, you must first disconnect the hub
from the mains power supply. For full safety
instructions, refer to the user guide that
accompanies the hub.
L'information de Sécurité Importante
AVERTISSEMENT: L'installation et l'enlèvement
de l'unité doivent être faits seulement par le
personnel qualifié. Avant d'installer le module
dans une unité ou de l'en retirer, vous devez
d'abord déconnecter les alimentations
électriques de l'unité. Pour plus de details sur
les instructions de sécurité, veuillez vous reférer
au guide utilisateur qui accompagne cette
unité.
Wichtige Sicherheitsinformationen
WARNUNG: Ein- und Ausbau des Gerätes ist
nur von Fachpersonal vorzunehmen. Vor der
Installation des Module in das Gerät muß das
Gerät vom Netz getrennt werden. Bitte
beachten Sie die Sicherheitsinformationen im
Handbuch des Gerät.
Installing the Module into a Hub
CAUTION: Do not install the Module in
unsuitable hubs such as those in the Hub 10,
PS Hub, and Hub 100 ranges. Contact your
supplier for advice if necessary.
1 Ensure that the hub is disconnected from the
mains power supply, and you are wearing an
anti-static wristband connected to a suitable
earth point.
2 Place the hub on a flat surface. Using a
suitable screwdriver, remove one blanking
plate from the rear of the hub to reveal a
slot for the Module. Do not remove any
other screws from the rear of the hub.
3 Keep the blanking plate in a safe place.
If you remove the Module, you must replace
the blanking plate to prevent dust and
debris entering the hub and maintain
cooling air circulation.
4 Hold the Module so that the text on the
front panel is upright, and slide it into the
hub, ensuring the edge connector is fully
engaged. The front panel of the Module
should lie flush against the rear panel of the
hub. Fix the front panel of the Module to
the hub using the two screws from the
blanking plate.
5 Power up the hub.
6 Check the LEDs on the hub to ensure that
the Module is operating correctly.
Setting the MDI/MDIX Switch
The Module has a slide switch on the front
panel for configuring the port as MDI or
MDIX. The Module is supplied with the switch
set to MDI.
The general rule for setting the switch is:
LEFT — Set to MDIX (cross-over) — for
connecting the Module port to an endstation
or server, using a 'straight through' cable.
RIGHT (factory setting) — Set to MDI — for
connecting the Module port to an MDIX port
on another hub or switch, using a 'straight
through' cable.
Connecting the Module
1 Insert the RJ45 connector on your cable
into the socket on the Module. Connect the
other end of the cable to an appropriate
device with a 100Mbps Fast Ethernet
100BASE-TX twisted pair interface. The
100BASE-TX port supports Category 5 cable
over a maximum length of 100m (328ft).
LEDs
LEDs on the front of the hub indicate the
Module status. Refer to the user guide that
accompanies the Dual Speed Hub 500 unit for
a description of the LED behavior.
Figure 2 Chaining Dual Speed Hub 500 stacks with 100BASE-TX Distance Extender Modules
Using the Distance Extender
The Distance Extender will connect to any Fast
Ethernet device with a twisted pair port. Links
of Category 5 cable may be a maximum
length of 100m.
You can connect two or more Dual Speed Hub
500 units using a Distance Extender at one
end of the link to form chains of units or
stacks. Figure 2 shows the process of chain
building.
You may install Distance Extender Modules in
any combination of transceiver slots within a
Dual Speed Hub 500 stack.
Take care not to create loops in the network.
For distances greater than 100m, use the
100BASE-FX Distance Extender.
Problem Solving
If you suspect a problem, carry out the
following checks before contacting your
supplier:
Ensure the unit in which the Module is fitted
is powered up.
Ensure the Module is correctly installed.
Ensure that the device at the far end of the
segment is powered up and operating
correctly.
Ensure you are using the correct cable.
Ensure that the cable and connectors are free
from damage and that the RJ45 connector at
each end of the cable is correctly engaged in
its appropriate socket.
Check that the MDI/MDIX setting is correct
for your configuration. See "Setting the
MDI/MDIX Switch", above.
Connections from Distance Extender to
Dual Speed Hub 500 TP port (or any other
Fast Ethernet TP device)