3Com Switch 3C16751A User Manual

®
OfficeConnect Dual Speed Hub 16  
User Guide (3C16751A)  
 
Introduction 5  
Environmental Statements 18  
End Of Life Statement 18  
Creating your Network 6  
Regulated Materials Statement 18  
Dual Speed Hub 16—Front 6  
Dual Speed Hub 16—Rear 7  
Before You Start 8  
Environmental Statement about the Documentation 18  
Environmental Statement about the Product Packaging 18  
Workstation Connections 8  
Important Safety Information 19  
Consignes importantes de sécurité 21  
Twisted Pair (TP) Cables 8  
Hub Connections 8  
Stacking the Units Together 9  
The Rubber Feet 9  
Technical Support 22  
The Stacking Clip 9  
Online Technical Services 22  
World Wide Web Site 22  
Positioning Your Hub 10  
Securing Your Hub 10  
3Com Knowledgebase Web Services 22  
Support from Your Network Supplier 23  
Support from 3Com 23  
Connecting Workstations and Other Equipment to Your Hub 11  
Connecting Another OfficeConnect Hub 11  
Fast Ethernet (100Mbps) Configuration Rules 11  
Ethernet (10Mbps) Configuration Rules 12  
Making the Connection to Another Hub 13  
Checking Hub Connections 13  
Spot Checks 13  
Returning Products for Repair 26  
3Com Corporation Limited Warranty 27  
Electromagnetic Compatibility 30  
Problem Solving 14  
Networking Terminology 16  
Dimensions and Standards 17  
Dimensions and Operating Conditions 17  
Standards 17  
3
 
4
 
INTRODUCTION  
Welcome to the world of networking with 3Com®. In the  
modern business environment, communication and sharing  
information is crucial. Computer networks have proved to  
be one of the fastest modes of communication but, until  
recently, only large businesses could afford the networking  
advantage. The OfficeConnect® product range from 3Com  
has changed this, bringing networks to the small office.  
If you wish to extend an existing Ethernet network into Fast  
Ethernet, adding a Dual Speed Hub 16 can offer a more  
cost-effective migration path than adding both a 100Mbps  
hub and a 10/100Mbps switch.  
Figure 1 Small Network With OfficeConnect Hub  
OfficeConnect  
Dual Speed Hub 16  
The OfficeConnect Dual Speed Hub 16 is ideal for creating  
small networks. It is compact and attractively designed for  
desktop use and can be used with other OfficeConnect  
products. This product forms part of the OfficeConnect  
range which neatly stack together with the OfficeConnect  
stacking clip.  
The OfficeConnect Dual Speed Hub 16 is an easy-to-use  
Class II hub (repeater) with sixteen 10/100BASE-TX ports. It  
allows you to set up a network with both Ethernet  
(10Mbps) and Fast Ethernet (100Mbps) workstations and  
other devices (a Class II hub can be connected to another  
Fast Ethernet hub, a Class I hub cannot).  
10Mbps  
100Mbps  
If you need to connect more workstations, simply use the  
stacking clip to connect another OfficeConnect hub to form  
a stack.  
When referring to the OfficeConnect Dual Speed Hub 16,  
this guide uses the term ‘Hub’. Each port on the Hub can  
be connected to either a 10BASE-T (Ethernet) or a  
100BASE-TX (Fast Ethernet) device. The port senses the  
speed of the connected equipment and operates at the  
appropriate speed.  
5
 
 
CREATING YOUR NETWORK  
Dual Speed Hub 16—Front  
Alert LED  
Power LED  
green  
Indicates that  
the power  
supply to the  
Hub is  
Collision LEDs  
yellow  
Port Status LEDs  
Network Utilization  
LEDs  
orange  
green (100Mbps link) / yellow (10Mbps link)  
If the LED is on, the link between the port and the  
next piece of network equipment is OK. If the LED is  
off, nothing is connected, or the connected device is  
switched off, or there is a problem with the  
connection (refer to the “Problem Solving” section).  
If flashing, the port is partitioned, possibly due to a  
network loop.  
Off when the Hub is operating  
correctly. Lit for a short period of  
time after power on, for self test.  
If the LED is continuously lit, there  
may be a problem. Refer to the  
“Problem Solving” section.  
Flash each time a  
collision is detected on  
the Hub's 100Mbps or  
10Mbps segment.  
Collisions are a normal  
part of network  
operation.  
green / yellow / orange  
(top row:100Mbps;  
bottom row:10Mbps)  
Indicate how much the  
100Mbps and 10Mbps  
segments of your  
present.  
network are being used.  
Port Status  
Network Utilization  
100M  
1
9
2
3
4
5
6
7
8
100M  
Collision  
10M  
1% 2% 3% 6% 12% 25% 50% 80%  
10M  
10  
11  
12  
13  
14  
15  
16  
Alert  
Power  
OfficeConnect Dual Speed Hub 16  
Green = 100M Yellow = 10M Flash = Partitioned  
6
 
   
Dual Speed Hub 16—Rear  
10/100BASE-TX  
5V DC  
4A MAX  
8X  
16  
1X  
9X  
Uplink/Normal  
Sixteen 10/100BASE-TX ports  
Power Adapter socket  
Only use the power adapter  
that is supplied with this  
OfficeConnect Dual Speed  
Hub 16. Do not use any other  
adapter.  
Uplink/Normal switch  
Affects the operation of port 16.  
If you are connecting another  
hub to port 16, set to Uplink (in),  
otherwise set to Normal (out).  
Refer to the “Connecting  
Another OfficeConnect Hub”  
section.  
Use suitable TP cable with RJ-45  
connectors. You can connect the Hub  
to any workstation or other  
equipment that has a 10BASE-T or  
100BASE-TX port. Each port is capable  
of autosensing for 10Mbps or  
100Mbps operation.  
7
 
 
3 One suitable TP cable for each workstation.  
Before You Start  
In order to comply with the 10BASE-T standard, ports  
designed for workstation connections have been  
marked with the graphical symbol ‘x’. This denotes a  
crossover in the port’s internal wiring, for example 1x,  
2x, 3x...  
Your OfficeConnect hub comes with:  
One power adapter for use with the OfficeConnect hub.  
A Product Registration card for you to fill out and return.  
Four rubber feet.  
A stacking clip.  
Twisted Pair (TP) Cables  
To connect your workstations and other equipment to the  
Hub, use ‘straight-through’ TP cables with RJ-45 connectors  
(all OfficeConnect products use RJ-45 type connectors). A  
‘straight-through’ cable is one where each pin of one  
connector is connected to the same pin of the other  
connector. Cables can be shielded (screened) or unshielded;  
we recommend that you use shielded cable. Cables used for  
100BASE-TX or 10/100BASE-TX connections must be data  
grade (Category 5). Your supplier should stock suitable  
cables.  
Two unit labels and eight cable ties.  
An OfficeConnect Network Assistant CD-ROM.  
The extra parts mentioned in the next section are not  
supplied with the hub.  
Workstation Connections  
To connect workstations or other equipment to your hub,  
you need:  
1 One 10BASE-T,  
The maximum length of a single cable is 100m (328ft).  
Refer to “Fast Ethernet (100Mbps) Configuration Rules” on  
page 11 for further information on cable lengths in a  
100Mbps network.  
3
10/100BASE-TX, or  
100BASE-TX adapter card  
for each workstation.  
2
3Com produce a range of  
1
easy-to-install network  
adapters, which provide  
your workstation with a suitable connection.  
Hub Connections  
To connect other OfficeConnect units to your Hub, you need  
one suitable TP cable for each unit.  
2 An operating system (for example, Netware or Windows  
95/98) with network support configured, running on  
your workstations.  
8
 
       
To fit another unit:  
Stacking the Units Together  
The Rubber Feet  
1 Rest the second unit on top of the clip and align it with  
the front of the unit below.  
2 Press down gently on the unit to secure it onto the clip,  
ensuring the fastening pieces fit into the slots on the unit  
below, as shown in Figure 2 (picture 2).  
The four self-adhesive rubber feet prevent your hub from  
moving around on your desk. Only stick the feet to the  
marked areas at each corner of the underside of your hub if  
you intend to place the unit directly on top of the desk. Do  
not fix the feet if you are going to use the clip.  
Figure 2 Stacking Your Units Together  
1
2
Fastening  
Piece  
The Stacking Clip  
Fastening  
Piece  
The blue stacking clip allows you to stack your  
OfficeConnect units together neatly and securely.  
CAUTION: You can stack up to a maximum of four  
units. Smaller units must be stacked above larger  
units.  
To fit the clip:  
To remove the clip:  
1 Place your unit on a flat surface.  
1 Remove the top unit together with the clip. If you hook  
a finger around one of the the fastening pieces and then  
pull it gently from out of the slot, the clip should come  
away with the upper unit attached to it.  
2 Fit the clip across the top of the unit, as shown in  
Figure 2 (picture 1), ensuring that the longer sections of  
the fastening pieces are pointing downwards.  
3 Align the fastening pieces over the slots found on each  
2 Push the clip in the center, so it bends towards the base  
side of the unit.  
of the unit, and then separate once the clip is loose.  
4 Push the clip down gently to secure it, ensuring the  
fastening pieces snap into the slots on the unit.  
9
 
       
Positioning Your Hub  
Securing Your Hub  
When installing your OfficeConnect hub, ensure:  
There are two slots on the underside of the OfficeConnect  
hub which can be used for wall mounting. It is  
recommended that you mount the hubs with the LEDs  
facing upwards to prevent dust entering the cooling vents.  
It is out of direct sunlight and away from sources of  
heat.  
Cabling is away from power lines, fluorescent lighting  
fixtures, and sources of electrical noise such as radios,  
transmitters and broadband amplifiers.  
When wall mounting the unit, ensure that it is within  
reach of the power outlet.  
Water or moisture cannot enter the case of the unit.  
You need two suitable screws. Ensure that the wall you are  
going to use is smooth, flat, dry and sturdy. Make two  
screw holes which are 142mm (5.6in.) apart. Use the  
template at the back of this guide to mark the position of  
the holes. Fix the screws into the wall, leaving their heads  
3mm (0.12in.) clear of the wall surface.  
Air flow around the unit and through the vents in the  
side of the case is not restricted. We recommend you  
provide a minimum of 25.4 mm (1in.) clearance.  
Remove any connections to the unit and locate it over the  
screw heads. When in line, gently push the unit on to the  
wall and move it downwards to secure. When making  
connections, be careful not to push the unit up and off the  
wall.  
CAUTION: Only wall mount single units, do not wall  
mount stacked units.  
Also available from 3Com, is the OfficeConnect Mounting  
Unit (part number 3C16765). This allows you to firmly  
secure a stack of OfficeConnect devices to the desktop or  
onto a shelf in a rack.  
10  
 
   
disconnect the cable, push the connectors latch in and  
remove it.  
Connecting Workstations and Other  
Equipment to Your Hub  
The Hub detects all port connections, so you can start using  
your network immediately. If you need more ports, simply  
add another OfficeConnect hub.  
WARNING: Please read the ‘Important Safety  
Information’ section before you start.  
WARNHINWEIS: Bitte lesen Sie den Abschnitt  
‘Wichtige Sicherheitsinformationen’ sorgfältig durch,  
bevor Sie das Gerät einschalten.  
Connecting Another OfficeConnect Hub  
You may wish to connect another OfficeConnect hub to  
your Dual Speed Hub 16. Alternatively, you may wish to add  
your Hub to an existing 10Mbps network. When extending  
your network, you should be aware of the configuration  
rules given below.  
AVERTISSEMENT: Veuillez lire attentivement la  
section “Consignes importantes de sécurité” avant de  
mettre en route.  
CAUTION: The equipment connected to the Hub  
must be set to operate in auto-negotiate or half  
duplex mode.  
If you connect two Dual Speed Hub 16 units directly  
together, the link between them operates at  
Connecting workstations and other equipment to your Hub  
is easy. To connect a workstation to any of the Hubs ports,  
use a ‘straight-through’ TP cable. Refer to “Twisted Pair (TP)  
Cables” on page 8 for further information.  
Fast Ethernet (100Mbps) Configuration Rules  
The Dual Speed Hub 16 is a Class II hub. You can connect  
directly two Class II Fast Ethernet hubs (Class I Fast Ethernet  
hubs cannot be connected directly to other Fast Ethernet  
hubs). The total length of cable (A + B + C) between two  
workstations, or between a workstation and a non-repeater  
piece of equipment (such as a switch), must not exceed  
205m (672ft). Each cable (A, B, or C) must not exceed  
100m (328ft).  
If you are using port 16 to connect a workstation,  
ensure the Uplink/Normal switch is set to Normal  
(out).  
TP cables are very easy to use. To connect a cable, simply  
slot the connector into the appropriate RJ-45 port. When  
the connector is fully in, its latch locks it in place. To  
11  
 
       
3Com recommends that the cable (B) between the Fast  
Ethernet hubs is no longer than 5m (16.4ft). This allows the  
maximum hub-to-workstation cable length (A or C) of 100m  
(328ft) to be used, as shown in Figure 3.  
Ethernet (10Mbps) Configuration Rules  
You can connect a maximum of four Ethernet (10Mbps)  
hubs in series between workstations, or between a  
workstation and a non-repeater piece of equipment (such as  
a switch). Each cable must not exceed 100m (328ft). An  
example is shown in Figure 4.  
Figure 3 Configuration Rules and Example of a Fast Ethernet  
(100Mbps) Network  
Figure 4 Example of an Ethernet (10Mbps) Network  
100Mbps  
Switch  
link  
A
B
C
Example:  
10Mbps  
link  
Switch  
Hub  
Hub  
Workstation  
Workstation  
Dual  
Speed  
Hub 16  
10Mbps  
Hub  
10Mbps  
Hub  
10Mbps  
Hub  
Workstation  
Workstation  
Example:  
100m (328ft)  
5m (16.4ft)  
100m (328ft)  
Workstation  
Dual  
100Mbps  
Hub  
Speed  
Hub 16  
Workstation  
12  
 
     
Figure 5 Correct Connections for OfficeConnect Hubs  
Making the Connection to Another Hub  
You can connect a 10BASE-T, 100BASE-TX, or another  
10/100BASE-TX OfficeConnect hub to any port on the Dual  
Speed Hub 16. Use the following method:  
OfficeConnect  
Dual Speed Hub16  
1 Using a straight-through cable, connect the  
Uplink/Normal port of the Dual Speed Hub 16 to any of  
the ports on the other hub (as shown in Figure 5). If  
using an Uplink/Normal port on the other hub, set its  
Uplink/Normal switch to Normal (out).  
Upl  
i
n
k/  
Nor  
m
al  
OfficeConnect  
hub  
2 Set the Uplink/Normal switch for the Uplink/Normal port  
Switch set to  
Uplink (in)  
on the Dual Speed Hub 16 to Uplink (in).  
Upl  
i
n
k/  
Nor  
m
al  
Checking Hub Connections  
When you have connected all the appropriate workstations  
and other equipment to the Hub, power on the Hub. For  
each port with a connection, a Port Status LED should be  
on. If the port is operating at 100Mbps, the corresponding  
LED in the upper row of Port Status LEDs is on. If the port is  
operating at 10Mpbs, the corresponding LED in the lower  
row is on. If neither LED is on, check your connections.  
Twisted pair cable  
with RJ-45 connectors.  
Maximum length is 100m (328ft)  
Spot Checks  
At frequent intervals, visually check that:  
The Alert LED is off — this is the best way to find out if  
there are problems with your network.  
Case vents are not obstructed.  
Cabling is secure and not pulled taut.  
13  
 
       
PROBLEM SOLVING  
The OfficeConnect Hub has been designed to aid you when  
detecting and solving possible problems with your network.  
These problems are rarely serious; the cause is usually a  
disconnected or damaged cable, or incorrect configuration.  
If this section does not solve your problem, contact your  
supplier for information on what to do next.  
There is a problem with the  
Alert LED continuously lit.  
network. Check the Port Status LEDs to try to identify the  
port that is causing the problem. If one of the Port Status  
LEDs is flashing, that port has partitioned, probably due to a  
network loop. Examine your connections and remove the  
loop. Each piece of equipment needs only one connection  
to your Hub.  
Perform these actions first:  
If you cannot identify such a port, remove the port  
connections one at a time, waiting a few seconds between  
each port. If the Alert LED goes off, there is either a  
network loop (see above), or an excessive amount of traffic  
on that port connection. Check the Network Utilization LEDs  
to see if the network is heavily loaded (over 80%). Some  
pieces of network equipment operate by sending out frames  
regularly. Refer to the documentation that accompanies the  
piece of network equipment.  
Ensure all network equipment is powered on.  
Power each piece of network equipment off, wait about  
5 seconds and then power each one on.  
Check the following symptoms and solutions:  
Power LED not lit. Check your power adapter connection.  
If there is still no power, you may have a faulty power  
adapter which needs replacing with an identical  
OfficeConnect power adapter. Do not use any other  
power adapter with the Hub.  
If the Alert LED is still lit after removing all of your  
connections, there may be a problem with your Hub. Turn  
off the power, wait about 5 seconds and then power on the  
hub. If the Alert LED comes back on continuously, contact  
your supplier.  
10Mbps Port Status LED lit for a port with a 100Mbps  
device connected. This may be because the cable is not of  
a high enough quality to carry Fast Ethernet signals (we  
recommend you use a Category 5 cable), or due to a  
problem with the network card (NIC) of the attached  
equipment.  
14  
 
 
Figure 6 Straight-through Cable/Crossover Cable  
Port Status LED flashing. The port is partitioned, probably  
due to a network loop. Examine your connections and  
remove the loop. Each piece of equipment needs only one  
connection to your Hub.  
Normal  
port  
Uplink Normal  
Normal  
port  
Pin  
1
Pin  
1
Pin  
1
Pin  
1
port  
port  
Rx-  
Rx+  
Rx+  
Rx-  
Rx+  
2
3
4
5
6
7
8
2
3
4
5
6
7
8
2
3
4
5
6
7
8
2
3
4
5
6
7
8
Rx+  
Tx-  
Rx-  
Link between the Hub and another OfficeConnect hub  
not working. Check your connections; follow the  
information given in the “Connecting Another  
OfficeConnect Hub” section on page 11. It is likely that an  
Uplink/Normal switch is incorrectly set.  
Rx-  
Tx+  
Tx+  
Tx+  
Tx+  
Tx-  
Tx-  
Tx-  
Port Status LED not lit for a port that has a  
connection. Check that you are using a ‘straight-through’  
cable which is properly connected at both ends, and is not  
damaged. Refer to “Twisted Pair (TP) Cables” on page 8.  
Also check that the equipment connected to the Hub is  
powered on, operating correctly and contains the correct  
type of connection. Refer to Figure 6 to compare the wiring  
of a straight-through and a crossover cable.  
15  
 
 
NETWORKING TERMINOLOGY  
A Network is a collection of workstations (for example,  
IBM-compatible PCs) and other equipment (for example,  
printers), connected for the purpose of exchanging  
information or sharing resources. Networks vary in size,  
some are within a single room, others span continents.  
A
segment  
is the length of cable connected to a port.  
Packets are the units of information your workstations and  
other equipment send to each other over the network. A  
frame is the data part of the packet and can be unicast  
(sent to a single device), multicast (sent to multiple  
A Local Area Network (LAN) is a network, usually in an  
devices), or  
broadcast  
(sent to all devices).  
office, that spans no more than a single site.  
Bandwidth refers to the amount of network traffic the  
Ethernet is a type of LAN, referring to the technology used  
to pass information around the network. It operates at  
10Mbps (megabits per second).  
network can hold at any one time (information capacity)  
measured in  
bits per second (bps)  
. Workstations or  
applications that use the network heavily are referred to as  
using high bandwidth. Fast Ethernet has a higher  
bandwidth than Ethernet, so it can cope with larger  
amounts of traffic, which results in faster operation.  
Fast Ethernet is a type of LAN that runs up to 10 times  
faster than standard Ethernet. It operates at 100Mbps.  
10BASE-T and 100BASE-TX are the names given to the  
Ethernet protocol that runs over Twisted Pair (TP) cable.  
10BASE-T runs at 10Mbps whilst 100BASE-TX operates at  
100Mbps. The OfficeConnect hub uses RJ-45 type  
connectors for connecting your TP network.  
A half duplex link allows information to flow in either  
direction, but not in either direction simultaneously.  
Collisions  
are part of normal ethernet operation and occur  
if other network equipment attempts to transmit at the  
same time. A sudden sustained increase in the number of  
collisions may indicate a problem with the device.  
A Network Loop occurs when two pieces of network  
equipment are connected by more than one path. Your hub  
detects this and partitions (isolates) one of its ports to  
break the loop.  
16  
 
 
DIMENSIONS AND STANDARDS  
Dimensions and Operating Conditions  
Standards  
Functional:  
ISO 8802/3  
IEEE 802.3  
33 VA  
58 BThU/hr  
power requirement  
228mm (9.12in.)  
Safety:  
EMC:  
UL 1950, EN 60950  
CSA 22.2 #950  
IEC 950  
54mm  
(2.1in.)  
0 to 40°C (32 to 105°F)  
operating  
temperature  
185mm (7.3in.)  
EN 55022 Class B†  
EN 50082-1  
0 to 90%  
(non-condensing)  
humidity  
1kg (2.2 lb)  
FCC Part 15 Class B*  
ICES-003 Class B†  
VCCI Class B†  
CNS 13438 Class A  
EN 60068 (IEC 68)  
Environmental:  
Category 5 screened cables must be used to ensure  
compliance with the Class B requirements of this standard.  
The use of unscreened cables (category 3 or category 5)  
complies with the Class A requirements.  
*Refer to “Electromagnetic Compatibility” on page 30 for  
conditions of operation.†  
17  
 
     
ENVIRONMENTAL STATEMENTS  
It is the policy of 3Com Corporation to be  
environmentally-friendly in all operations. To uphold our  
policy, we are committed to:  
End Of Life Statement  
3Com processes allow for the recovery, reclamation and safe  
disposal of all end-of-life electronic components.  
Establishing environmental performance standards that  
comply with national legislation and regulations.  
Regulated Materials Statement  
Conserving energy, materials and natural resources in all  
3Com products do not contain any hazardous or  
ozone-depleting material.  
operations.  
Reducing the waste generated by all operations.  
Environmental Statement about the Documentation  
Ensuring that all waste conforms to recognized  
The documentation for this product is printed on paper that  
comes from sustainable, managed forests; it is fully  
biodegradable and recyclable, and is completely  
chlorine-free. The varnish is environmentally-friendly, and the  
inks are vegetable-based with a low heavy-metal content.  
environmental standards.  
Maximizing the recyclable and reusable content of all  
products.  
Ensuring that all products can be recycled, reused and  
disposed of safely.  
Environmental Statement about the Product  
Packaging  
Ensuring that all products are labelled according to  
recognized environmental standards.  
The packaging for this product is fully recyclable. It has a  
recycled (post consumer) waste content of at least 40% by  
weight, and no heavy-metal content.  
Improving our environmental record on a continual basis.  
18  
 
         
IMPORTANT SAFETY INFORMATION  
WARNING: Warnings contain directions that you  
must follow for your personal safety. Follow all  
directions carefully.  
You must read the following safety information  
carefully before you install or remove the unit:  
There are no user-replaceable fuses or user-serviceable  
parts inside the hub. If you have a physical problem with  
the unit that cannot be solved with problem solving  
actions in this guide, contact your supplier.  
Disconnect the power adapter before moving the unit.  
Exceptional care must be taken during installation and  
WARNING: RJ-45 ports. These are shielded RJ-45  
data sockets. They cannot be used as telephone  
sockets. Only connect RJ-45 data connectors to these  
sockets.  
removal of the unit.  
Only stack the OfficeConnect hub with other  
OfficeConnect units.  
To ensure compliance with international safety standards,  
only use the power adapter that is supplied with the  
unit.  
The socket outlet must be near to the unit and easily  
accessible. You can only remove power from the unit by  
disconnecting the power cord from the outlet.  
This unit operates under SELV (Safety Extra Low Voltage)  
conditions according to IEC 950. The conditions are only  
maintained if the equipment to which it is connected  
also operates under SELV conditions.  
19  
 
 
WICHTIGE SICHERHEITSHINWEISE  
WARNHINWEIS: Warnhinweise enthalten  
Anweisungen, die Sie zu Ihrer eigenen Sicherheit  
befolgen müssen. Alle Anweisungen sind sorgfältig zu  
befolgen.  
Sie müssen die folgenden Sicherheitsinformationen  
sorgfältig durchlesen, bevor Sie das Geräts installieren  
oder ausbauen:  
Es sind keine von dem Benutzer zu ersetzende oder zu  
wartende Teile in dem Gerät vorhanden. Wenn Sie ein  
Problem mit dem Switch haben, das nicht mittels der  
Fehleranalyse in dieser Anleitung behoben werden kann,  
setzen Sie sich mit Ihrem Lieferanten in Verbindung.  
Vor dem Ausbau des Geräts das Netzadapterkabel  
herausziehen.  
Bei der Installation und beim Ausbau des Geräts ist mit  
WARNHINWEIS: RJ-45-Anschlüsse. Dies sind  
abgeschirmte RJ-45-Datenbuchsen. Sie können nicht  
als Telefonanschlußbuchsen verwendet werden. An  
diesen Buchsen dürfen nur RJ-45-Datenstecker  
angeschlossen werden.  
höchster Vorsicht vorzugehen.  
Stapeln Sie das Geräts nur mit anderen OfficeConnect  
Gerätes zusammen.  
Aufgrund von internationalen Sicherheitsnormen darf das  
Gerät nur mit dem mitgelieferten Netzadapter verwendet  
werden.  
Die Netzsteckdose muß in der Nähe des Geräts und  
leicht zugänglich sein. Die Stromversorgung des Geräts  
kann nur durch Herausziehen des Gerätenetzkabels aus  
der Netzsteckdose unterbrochen werden.  
Der Betrieb dieses Geräts erfolgt unter den  
SELV-Bedingungen (Sicherheitskleinstspannung) gemäß  
IEC 950. Diese Bedingungen sind nur gegeben, wenn  
auch die an das Gerät angeschlossenen Geräte unter  
SELV-Bedingungen betrieben werden.  
20  
 
 
CONSIGNES IMPORTANTES DE SÉCURITÉ  
AVERTISSEMENT: Les avertissements présentent des  
consignes que vous devez respecter pour garantir  
votre sécurité personnelle. Vous devez respecter  
attentivement toutes les consignes.  
Nous vous demandons de lire attentivement les  
consignes suivantes de sécurité avant d’installer ou de  
retirer l’appareil:  
Il n’y a pas de parties remplaceables par les utilisateurs  
ou entretenues par les utilisateurs à l’intérieur du moyeu.  
Si vous avez un problème physique avec le moyeu qui ne  
peut pas être résolu avec les actions de la résolution des  
problèmes dans ce guide, contacter votre fournisseur.  
Débranchez l'adaptateur électrique avant de retirer cet  
appareil.  
Faites très attention lors de l'installation et de la dépose  
AVERTISSEMENT: Ports RJ-45. Il s'agit de prises  
femelles blindées de données RJ-45. Vous ne pouvez  
pas les utiliser comme prise de téléphone. Branchez  
uniquement des connecteurs de données RJ-45 sur  
ces prises femelles.  
du groupe.  
Seulement entasser le moyer avec les autres moyeux  
OfficeConnects.  
Pour garantir le respect des normes internationales de  
sécurité, utilisez uniquement l'adaptateur électrique remis  
avec cet appareil.  
La prise secteur doit se trouver à proximité de l’appareil  
et son accès doit être facile. Vous ne pouvez mettre  
l’appareil hors circuit qu'en débranchant son cordon  
électrique au niveau de cette prise.  
L’appareil fonctionne à une tension extrêmement basse  
de sécurité qui est conforme à la norme CEI 950. Ces  
conditions ne sont maintenues que si l'équipement  
auquel il est raccordé fonctionne dans les mêmes  
conditions.  
21  
 
 
TECHNICAL SUPPORT  
3Com provides easy access to technical support information  
through a variety of services. This section describes these  
services.  
This service provides access to online support information  
such as technical documentation and software, as well as  
support options that range from technical education to  
maintenance and professional services.  
Information contained in this section is correct at time of  
publication. For the most recent information, 3Com  
recommends that you access the 3Com Corporation World  
Wide Web site.  
3Com Knowledgebase Web Services  
This interactive tool contains technical product information  
compiled by 3Com expert technical engineers around the  
globe. Located on the World Wide Web at:  
Online Technical Services  
.
3Com offers worldwide product support 24 hours a day,  
7 days a week, through the following online systems:  
This service gives all 3Com customers and partners  
complementary, round-the-clock access to technical  
information on most 3Com products.  
World Wide Web site.  
3Com Knowledgebase Web Services.  
World Wide Web Site  
To access the latest networking information on the  
3Com Corporation World Wide Web site, enter this URL  
into your Internet browser:  
22  
 
       
Support from Your Network Supplier  
Support from 3Com  
If you require additional assistance, contact your network  
supplier. Many suppliers are authorized 3Com service  
partners who are qualified to provide a variety of services,  
including network planning, installation, hardware  
maintenance, application training, and support services.  
If you are unable to obtain assistance from the 3Com online  
technical resources or from your network supplier, 3Com  
offers technical telephone support services. To find out more  
about your support options, call the 3Com technical  
telephone support phone number at the location nearest  
you.  
When you contact your network supplier for assistance,  
have the following information ready:  
When you contact 3Com for assistance, have the following  
information ready:  
Product model name, part number, and serial number.  
Product model name, part number, and serial number.  
A list of system hardware and software, including revision  
levels.  
A list of system hardware and software, including revision  
levels.  
Diagnostic error messages.  
Diagnostic error messages.  
Details about recent configuration changes, if applicable.  
Details about recent configuration changes, if applicable.  
If you are unable to contact your network supplier, see the  
following section on how to contact 3Com.  
23  
 
   
Here is a list of worldwide technical telephone support  
numbers:  
Country  
Telephone Number  
Country  
Telephone Number  
Asia, Pacific Rim  
Australia  
Hong Kong  
India  
Indonesia  
Japan  
Malaysia  
New Zealand  
Pakistan  
Philippines  
1 800 678 515  
800 933 486  
P. R. o f C hin a  
10800 61 00137 or  
021 6350 1590  
800 6161 463  
+61 2 9937 5085  
001 800 61 009  
0031 61 6439  
1800 801 777  
0800 446 398  
+61 2 9937 5085  
1235 61 266 2602  
Singapore  
S. Korea  
From anywhere in S. Korea: 00798 611 2230  
From Seoul:  
Taiwan, R.O.C.  
Thailand  
(0)2 3455 6455  
0080 611 261  
001 800 611 2000  
Europe  
From anywhere in Europe, call: +31 (0)30 6029900 phone  
+31 (0)30 6029999 fax  
Europe, South Africa, and Middle East  
From the following countries, you may use the toll-free numbers:  
Austria  
Belgium  
Denmark  
Finland  
France  
Germany  
Hungary  
Ireland  
Israel  
0800 297468  
0800 71429  
800 17309  
0800 113153  
0800 917959  
0800 1821502  
00800 12813  
1800 553117  
1800 9453794  
1678 79489  
Netherlands  
Norway  
Poland  
Portugal  
South Africa  
Spain  
Sweden  
Switzerland  
U.K.  
0800 0227788  
800 11376  
00800 3111206  
0800 831416  
0800 995014  
900 983125  
020 795482  
0800 55 3072  
0800 966197  
Italy  
24  
 
Country  
Telephone Number  
Country  
Telephone Number  
Latin America  
Argentina  
Brazil  
Chile  
Colombia  
AT&T +800 666 5065  
0800 13 3266  
1230 020 0645  
98012 2127  
Mexico  
Peru  
Puerto Rico  
Venezuela  
01 800 CARE (01 800  
2273)  
AT&T +800 666 5065  
800 666 5065  
AT&T +800 666 5065  
North America  
1 800 876-3266  
25  
 
Country  
Telephone Number  
Fax Number  
Returning Products for Repair  
Austria  
0800 297468  
0800 71429  
800 17309  
Before you send a product directly to 3Com for repair, you  
must first obtain a Return Material Authorization (RMA)  
number. Products sent to 3Com without authorization  
numbers will be returned to the sender unopened, at the  
senders expense.  
Belgium  
Denmark  
Finland  
France  
Germany  
Hungary  
Ireland  
0800 113153  
0800 917959  
0800 1821502  
00800 12813  
1800553117  
1800 9453794  
1678 79489  
0800 0227788  
800 11376  
00800 3111206  
0800 831416  
0800 995014  
900 983125  
020 795482  
0800 55 3072  
0800 966197  
Israel  
Italy  
To obtain an authorization number, call or fax:  
Netherlands  
Norway  
Poland  
Portugal  
South Africa  
Spain  
Sweden  
Switzerland  
U.K.  
Country  
Telephone Number  
+ 65 543 6500  
Fax Number  
Asia, Pacific Rim  
+ 65 543 6348  
Europe, South Africa,  
and Middle East  
+ 31 30 6029900  
+ 31 30  
6029999  
Latin America  
1 408 326 2927  
1 408 326 3355  
From the following countries, you may call the toll-free numbers;  
select option 2 and then option 2:  
U.S.A. and Canada  
1 800 876 3266  
1 408 326 7120  
(not toll-free)  
26  
 
 
specifications. Customer assumes responsibility for the selection of the  
appropriate applications program and associated reference materials. 3Com  
makes no warranty or representation that its software products will meet  
Customer’s requirements or work in combination with any hardware or  
applications software products provided by third parties, that the operation of the  
software products will be uninterrupted or error free, or that all defects in the  
software products will be corrected. For any third party products listed in the  
3Com software product documentation or specifications as being compatible,  
3Com will make reasonable efforts to provide compatibility, except where the  
non-compatibility is caused by a "bug" or defect in the third party's product or  
from use of the software product not in accordance with 3Com’s published  
specifications or user manual.  
3Com Corporation LIMITED WARRANTY  
3Com OfficeConnect Dual Speed Hub 16  
The duration of the warranty for the OfficeConnect Dual Speed Hub 16  
(3C16751A) is lifetime, including the power adapter.  
Advance hardware exchange is available during the first year from your date of  
purchase in accordance with 3Com’s standard terms and conditions for such  
service. After the first year the warranty reverts to 3Com’s standard lifetime  
limited warranty.  
To qualify for the lifetime limited warranty and the advance hardware exchange  
you must submit the appropriate product warranty registration card to 3Com,  
otherwise this product will be warranted for a period of one (1) year without  
advance hardware exchange.  
YEAR 2000 WARRANTY  
In addition to the Hardware Warranty and Software Warranty stated above,  
3Com warrants that each product sold or licensed to Customer on and after  
January 1, 1998 that is date sensitive will continue performing properly with  
regard to such date data on and after January 1, 2000, provided that all other  
products used by Customer in connection or combination with the 3Com  
product, including hardware, software, and firmware, accurately exchange date  
data with the 3Com product, with the exception of those products identified at  
this standard. If it appears that any product that is stated to meet this standard  
does not perform properly with regard to such date data on and after January 1,  
2000, and Customer notifies 3Com before the later of April 1, 2000, or ninety  
(90) days after purchase of the product from 3Com or its authorized reseller,  
3Com shall, at its option and expense, provide a software update which would  
effect the proper performance of such product, repair such product, deliver to  
Customer an equivalent product to replace such product, or if none of the  
foregoing is feasible, refund to Customer the purchase price paid for such  
product.  
HARDWARE  
3Com warrants this hardware product to be free from defects in workmanship  
and materials, under normal use and service, for the following length of time  
from the date of purchase from 3Com or its authorized reseller:  
One (1) year (unless otherwise specified above)  
3Com’s sole obligation under this express warranty shall be, at 3Com’s option  
and expense, to repair the defective product or part, deliver to Customer an  
equivalent product or part to replace the defective item, or if neither of the two  
foregoing options is reasonably available, 3Com may, in its sole discretion, refund  
to Customer the purchase price paid for the defective product. All products that  
are replaced will become the property of 3Com. Replacement products may be  
new or reconditioned. 3Com warrants any replaced or repaired product or part  
for ninety (90) days from shipment, or the remainder of the initial warranty  
period, whichever is longer.  
Any software update or replaced or repaired product will carry a Year 2000  
Warranty for ninety (90) days after purchase or until April 1, 2000, whichever is  
later.  
SOFTWARE  
3Com warrants that each software program licensed from it will perform in  
substantial conformance to its program specifications, for a period of ninety (90)  
days from the date of purchase from 3Com or its authorized reseller. 3Com  
warrants the media containing software against failure during the warranty  
period. No updates are provided. 3Com's sole obligation under this express  
warranty shall be, at 3Com's option and expense, to refund the purchase price  
paid by Customer for any defective software product, or to replace any defective  
media with software which substantially conforms to applicable 3Com published  
OBTAINING WARRANTY SERVICE  
Customer must contact a 3Com Corporate Service Center or an Authorized 3Com  
Service Center within the applicable warranty period to obtain warranty service  
authorization. Dated proof of purchase from 3Com or its authorized reseller may  
be required. Products returned to 3Com's Corporate Service Center must be  
pre-authorized by 3Com with a Return Material Authorization (RMA) number  
27  
 
 
marked on the outside of the package, and sent prepaid and packaged  
appropriately for safe shipment, and it is recommended that they be insured or sent  
by a method that provides for tracking of the package. The repaired or replaced  
item will be shipped to Customer, at 3Com's expense, not later than thirty (30) days  
after 3Com receives the defective product.  
WARRANTIES EXCLUSIVE  
IF A 3COM PRODUCT DOES NOT OPERATE AS WARRANTED ABOVE,  
CUSTOMER'S SOLE REMEDY FOR BREACH OF THAT WARRANTY SHALL BE  
REPAIR, REPLACEMENT, OR REFUND OF THE PURCHASE PRICE PAID, AT 3COM'S  
OPTION. TO THE FULL EXTENT ALLOWED BY LAW, THE FOREGOING  
WARRANTIES AND REMEDIES ARE EXCLUSIVE AND ARE IN LIEU OF ALL OTHER  
WARRANTIES, TERMS, OR CONDITIONS, EXPRESS OR IMPLIED, EITHER IN FACT  
OR BY OPERATION OF LAW, STATUTORY OR OTHERWISE, INCLUDING  
WARRANTIES, TERMS, OR CONDITIONS OF MERCHANTABILITY, FITNESS FOR A  
PARTICULAR PURPOSE, SATISFACTORY QUALITY, CORRESPONDENCE WITH  
DESCRIPTION, AND NON-INFRINGEMENT, ALL OF WHICH ARE EXPRESSLY  
DISCLAIMED. 3COM NEITHER ASSUMES NOR AUTHORIZES ANY OTHER PERSON  
TO ASSUME FOR IT ANY OTHER LIABILITY IN CONNECTION WITH THE SALE,  
INSTALLATION, MAINTENANCE OR USE OF ITS PRODUCTS.  
Dead- or Defective-on-Arrival. In the event a product completely fails to function  
or exhibits a defect in materials or workmanship within the first forty-eight (48)  
hours of installation but no later than thirty (30) days after the date of purchase,  
and this is verified by 3Com, it will be considered dead- or defective-on-arrival  
(DOA) and a replacement shall be provided by advance replacement. The  
replacement product will normally be shipped not later than three (3) business  
days after 3Com’s verification of the DOA product, but may be delayed due to  
export or import procedures. When an advance replacement is provided and  
Customer fails to return the original product to 3Com within fifteen (15) days  
after shipment of the replacement, 3Com will charge Customer for the  
replacement product, at list price.  
3COM SHALL NOT BE LIABLE UNDER THIS WARRANTY IF ITS TESTING AND  
EXAMINATION DISCLOSE THAT THE ALLEGED DEFECT OR MALFUNCTION IN THE  
PRODUCT DOES NOT EXIST OR WAS CAUSED BY CUSTOMER'S OR ANY THIRD  
PERSON'S MISUSE, NEGLECT, IMPROPER INSTALLATION OR TESTING,  
UNAUTHORIZED ATTEMPTS TO OPEN, REPAIR OR MODIFY THE PRODUCT, OR  
ANY OTHER CAUSE BEYOND THE RANGE OF THE INTENDED USE, OR BY  
ACCIDENT, FIRE, LIGHTNING, OTHER HAZARDS, OR ACTS OF GOD.  
3Com shall not be responsible for any software, firmware, information, or memory  
data of Customer contained in, stored on, or integrated with any products returned  
to 3Com for repair, whether under warranty or not.  
ADDITIONAL SERVICES:  
Telephone Support. This OfficeConnect® product comes with telephone technical  
support for ninety (90) days. The ninety (90) day period begins on the date of  
Customer's product purchase.  
The telephone technical support is available from 3Com from 9 a.m. to 5 p.m.,  
local time, Monday through Friday, excluding local holidays. Telephone technical  
support is limited to the 3Com products designated above and may include  
assistance with installation, product specific configuration, and identification of  
equipment problems. Please refer to the Technical Support appendix in the User  
Guide for telephone numbers.  
LIMITATION OF LIABILITY  
TO THE FULL EXTENT ALLOWED BY LAW, 3COM ALSO EXCLUDES FOR ITSELF  
AND ITS SUPPLIERS ANY LIABILITY, WHETHER BASED IN CONTRACT OR TORT  
(INCLUDING NEGLIGENCE), FOR INCIDENTAL, CONSEQUENTIAL, INDIRECT,  
SPECIAL, OR PUNITIVE DAMAGES OF ANY KIND, OR FOR LOSS OF REVENUE OR  
PROFITS, LOSS OF BUSINESS, LOSS OF INFORMATION OR DATA, OR OTHER  
FINANCIAL LOSS ARISING OUT OF OR IN CONNECTION WITH THE SALE,  
INSTALLATION, MAINTENANCE, USE, PERFORMANCE, FAILURE, OR INTERRUPTION  
OF ITS PRODUCTS, EVEN IF 3COM OR ITS AUTHORIZED RESELLER HAS BEEN  
ADVISED OF THE POSSIBILITY OF SUCH DAMAGES, AND LIMITS ITS LIABILITY TO  
REPAIR, REPLACEMENT, OR REFUND OF THE PURCHASE PRICE PAID, AT 3COM'S  
OPTION. THIS DISCLAIMER OF LIABILITY FOR DAMAGES WILL NOT BE AFFECTED  
IF ANY REMEDY PROVIDED HEREIN SHALL FAIL OF ITS ESSENTIAL PURPOSE.  
Response to requests for telephone technical support will be in the form of a  
return call from a 3Com representative by close of business the following business  
day.  
To qualify for this 90 days of telephone technical support, you must register on  
of purchase, product number, and serial number. 3Com reserves the right to  
modify or cancel this telephone support offering at any time, without advance  
notice. This offer is not available where prohibited or restricted by law.  
3Com’s Web and Bulletin Board Service are available at no charge, and provide  
software and firmware upgrades, a bug list, and technical information about  
3Com products.  
28  
 
DISCLAIMER  
Some countries, states, or provinces do not allow the exclusion or limitation of  
implied warranties or the limitation of incidental or consequential damages for  
certain products supplied to consumers, or the limitation of liability for personal  
injury, so the above limitations and exclusions may be limited in their application  
to you. When the implied warranties are not allowed to be excluded in their  
entirety, they will be limited to the duration of the applicable written warranty.  
This warranty gives you specific legal rights which may vary depending on local  
law.  
GOVERNING LAW  
This Limited Warranty shall be governed by the laws of the State of California,  
U.S.A. excluding its conflicts of laws principles and excluding the United Nations  
Convention on Contracts for the International Sale of Goods.  
3Com Corporation  
5400 Bayfront Plaza  
Santa Clara, CA 95054  
(408) 326-5000  
29  
 
ELECTROMAGNETIC COMPATIBILITY  
VCCI STATEMENT  
FCC STATEMENT  
This equipment has been tested and found to comply with the limits for a Class B  
digital device, pursuant to Part 15 of the FCC Rules, and the Canadian  
Department of Communications Equipment Standards entitled, “Digital  
Apparatus,” ICES-003. These limits are designed to provide reasonable protection  
against harmful interference in a residential installation. This equipment  
generates, uses and can radiate radio frequency energy and, if not installed and  
used in accordance with the instructions, may cause harmful interference to radio  
communications. However, there is no guarantee that interference will not occur  
in a particular installation.  
BCIQ STATEMENT  
If this equipment does cause interference to radio or television reception, which  
can be determined by turning the equipment off and on, the user is encouraged  
to try to correct the interference by one or more of the following measures:  
Reorient the receiving antenna.  
Relocate the equipment with respect to the receiver.  
Move the equipment away from the receiver.  
Plug the equipment into a different outlet so that equipment and receiver are  
on different branch circuits.  
INFORMATION TO THE USER  
The user may find the following booklet prepared by the Federal Communications  
Commission helpful:  
Consult the dealer or an experienced radio/television technician for help.  
How to Identify and Resolve Radio-TV Interference Problems  
CSA STATEMENT  
This booklet is available from the U.S. Government Printing Office, Washington,  
DC 20402, Stock No. 004-000-00345-4.  
This Class B digital apparatus meets all requirements of the Canadian  
Interference-Causing Equipment Regulations.  
In order to meet FCC emissions limits, this equipment must be used only with  
cables which comply with IEEE 802.3.  
Cet appareil numérique de la classe B respecte toutes les exigences du Règlement  
sur le matériel brouilleur du Canada.  
30  
 
   
Wall mounting screw hole guide  
142mm (5.6in.)  
31  
 
Part No. DUA 1675-1AAA02  
Published June 1999  
32  
 

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