ACCESSBUILDER 7000
TRIPLE MODEM MODULE
USER GUIDE
®
Part No. 980/000048/001
Published June 1996
IMPORTANT SAFETY INFORMATION
WARNING: Warnings contain directions that you must follow for your
personal safety. Follow all instructions carefully.
Please read carefully and thoroughly the following information before
installing the AccessBuilder 7000 Triple Modem Module:
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Exceptional care must be taken during installation and removal of the
module.
The safety status of the interconnection ports on this equipment are as
follows:
Ports identified by the label PSTN and LEASE = TNV
Ports identified by the labels DTE = SELV
TNV (telecoms network voltage) is a circuit which under normal
operating conditions carries telecommunication signals.
SELV (safety extra low voltage) is a secondary circuit which is designed
and protected so that under normal and single-fault conditions, the
voltage between any two accessible parts does not exceed a safe value
(42.2 V peak or 60 V DC).
Only connect apparatus complying with the relevant interface
requirements to the ports on this unit.
WICHTIGE SICHERHEITSHINWEISE
ACHTUNG: Die Warnungen enthalten Anweisungen, die Sie zur
eigenen Sicherheit zu befolgen haben.
Lesen Sie bitte die folgenden Informationen sorgfältig durch, bevor Sie
den AccessBuilder 7000 Triple Modem Module einbauen:
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Auf besondere Vorsicht muß während des Ein- und Ausbaus des
Einheits geachtet werden.
Der Sicherheitsstandard der Anschlüsse fuer dieses Gerät sind wie folgt:
Anschlüsse bezeichnet mit PSTN und LEASE = TNV
Anschlüsse bezeichnet mit DTE = SELV
TNV (Telecoms Network Voltage - Spannung des
Telekommunikationsnetzwerks) ist ein Anschluss, der unter normalen
Umständen Telekommunikationssignale enthält .
SELV (Safety Extra Low Voltage - Extra Sicherheitsspannung) ist ein
weiterer Anschluss, der unter normalen Umständen und
Fehlerkonditionen entworfen und gesichert wurde, so dass die
Spannung zwischen zwei erreichbaren Teilen kein gefährliches Niveau
erreicht (42.2V max. oder 60V DC).
An den Anschlussbuchsen der Geräte dürfen nur die dafür
vorgesehenen Anschlüsse verwendet werden.
L’INFORMATION DE SÉCURITÉ
IMPORTANTE
AVERTISSEMENT: Les avertissements contiennent les instructions que
vous devez suivre pour votre sécurité personnelle. Suivre toutes les
instructions avec soin.
Veuillez lire à fond l’information suivante avant d’installer le moyeu:
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Le soin exceptionnel doit être pris pendant l’installation et l’enlèvement
du moyeu.
Les normes de sécurité des ports d'interconnexion sur cet équipement
sont les suivants:
Les ports marqués par les etiquettes PSTN et LEASE = TNV
Les ports marqués par les etiquettes DTE = SELV
TNV (Telecoms Network Voltage - tension réseau de
télécommunications) est un circuit qui dans des conditions
d'opérations normales, transfert les signeaux télécoms.
SELV (Safety Extra Low Voltage - tension de sécurité extra-réduite) est
un circuit secondaire désigné et protègé qui dans des conditions
normales et de fautes uniques, assure que la tension entre deux
éléments accessibles n'accedéra pas un niveau de sécurité (42.2V max.
ou 60 V DC).
Connecter uniquement des unités conformes aux normes relatives des
interfaces de cet équipement.
WICHTIGE SICHERHEITSHINWEISE
Introduction
How to Use This Guide
Conventions
Additional Safety Information
1
2
1 TRIPLE MODEM MODULE
Introduction 1-1
Pack Contents Checklist 1-6
Pre-installation Requirements 1-7
2 INSTALLATION AND OPERATION
Overview 2-1
Installing The Module 2-2
Installing the Rear Card 2-3
Installing the Front Card 2-4
Connecting the Cables 2-5
Modem Lines 1-3 2-5
DTE Ports 1- 3 2-5
Front Panel LEDs 2-6
Troubleshooting Guide 3-1
Modem Health 3-1
Modem - DTE Connection 3-2
Modem - Telephone Line Connection 3-3
Private-line Operation 3-6
ASSIGNMENTS
Interference and Safety Requirements A-5
PBX and PABX Application A-6
Ringer Equivalence A-7
DTE Port Pin Assignments A-8
X.21/V.11 A-8
V.24/V.28 A-9
V.35/V.36 A-10
PSTN Port Cable Pin Assignments A-11
Private Line Port Cable Pin Assignments A-12
B TECHNICAL SUPPORT
On-line Technical Services D-1
3Com Bulletin Board Service D-1
Access by Modem D-1
Access by ISDN D-2
World Wide Web Site D-2
Support from 3Com D-4
Returning Products for Repair D-5
INDEX
LIMITED WARRANTY
FCC CLASS A VERIFICATION STATEMENT
ABOUT THIS GUIDE
Introduction
This guide describes the features, installation and configuration of the
AccessBuilder 7000 Triple Modem Module.
This guide assumes that you have installed your AccessBuilder 7000
Access Concentrator and that the phone lines to which you want to
connect the modems are installed and operational.
How to Use This Guide
This table shows where to find specific information:
If you are looking for information on:
Turn to:
The Triple Modem Module’s features and typical
uses.
Chapter 1
Installation and descriptions of the front panel
LEDs and rear panel connectors.
Chapter 2
Troubleshooting and problem solving.
Technical information and cable specifications.
ASCII character table.
Chapter 3
Appendix A
Appendix B
Appendix C
Appendix D
Regulatory information.
Technical support.
2
ABOUT THIS GUIDE
Conventions
The icon conventions that are used throughout this guide are:
Icon
Type
Description
Information Note
Information notes call attention to
important features or instructions.
Caution
Warning
Cautions alert you to personal safety
risk, system damage, or loss of data.
Warnings alert you to the risk of
severe personal injury.
The text conventions used in this guide are:
Convention
Description
“Enter” vs. “Type”
When the word “enter” is used in this guide,
it means type something, then press the
[Return] or [Enter] key. Do not press the
[Return] or [Enter] key when an instruction
simply says “type.”
Text represented as
This typefaceis used to represent
screen display displays on your screen, for example:
Enter the unit’s IP address:
Text represented as
This typeface is used to represent
commands
commands that you enter, for example:
CO IS NU
Keys
When specific keys are referred to in the
text, they are called out by their labels, such
as “the Return key” or “the Escape key,” or
they may be shown as [Return] or [Esc].
If two or more keys are to be pressed
simultaneously, the keys are linked with a
plus sign (+), for example:
Press [Ctrl]+[Alt]+[Del].
Italics
Italics are used to denote new terms or
emphasis.
Additional Safety Information
3
Additional Safety Information
See also the Important Safety Information at the front of this guide.
When using the unit, observe the following safety information:
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Retain this user’s guide for later use and pass it on in the event of
change of ownership of the unit.
Products manufactured by us are safe and without risk provided they
are installed, used and maintained in good working order in
accordance with our instructions and recommendations.
■
If any of the following conditions occur, isolate the electricity supply
and refer to your 3Com reseller.
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If the module is damaged.
If the module begins to make an odd noise, smell or smoke.
If the module shows signs of a distinct change in performance.
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Never install telephone wires during a lightening storm, or install
telephone connection sockets in wet locations, unless the socket is
specifically designed for wet locations.
Do not touch uninstalled telephone wires or terminals unless the
telephone line has been disconnected at the network interface. Always
exercise caution when installing or modifying telephone lines.
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Do not spill food or liquids on the unit. If the unit gets wet, isolate the
electrical supply and contact your 3Com reseller.
Do not push any objects into the openings of the unit. Doing so can
cause fire or electric shock by shorting out internal components.
Be sure nothing rests on the unit’s system cables and that the cables are
not located where they can be stepped on and cause damage to the unit.
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Keep the unit away from radiators and heat sources.
Install the unit in a clean area free from dust or extreme temperatures.
Interconnecting directly, or by way of other apparatus, to ports
complying with SELV requirements may produce hazardous conditions
on the network. Advice should be sought from a competent engineer
before such a connection is made.
4
ABOUT THIS GUIDE
TRIPLE MODEM MODULE
1
Introduction
This chapter outlines the features and uses of the AccessBuilder 7000
Triple Modem Module when installed in the AccessBuilder 7000 Access
Concentrator chassis.
The Triple Modem Module houses three modems on a single device
module that operate independently of each other but are identical in
the features and facilities they offer. Each modem is a fully featured,
high speed device which provides reliable asynchronous and
synchronous operation over dialled or private line networks.
The high speed transfer of up to 33.6 Kbps over dialled lines is
guaranteed by using CCITT V.42bis/MNP Class 5 data compression and
CCITT V.42/MNP error correction. IN addition to the fast line speeds,
each modem can transfer data to the attached computer at speeds
which can vary from 300 bps to 115200 bps.
The modems are compatible with a number of dialling methods and
protocols, such as asynchronous AT commands and CCITT V.25bis
dialling, which allow you to uses the modems in a variety of
applications and environments. You can control each Triple Modem’s
configuration, dialling characteristics and diagnostic features. Five
factory set configurations, containing the most commonly-used Triple
Modem settings, are permanently stored in each Triple Modem’s
memory, providing a quick and easy method of a configuring a Triple
Modem to be compatible with asynchronous and synchronous data
environments over 2-wire or 4-wire Private lines or the PSTN.
1-2
CHAPTER 1: TRIPLE MODEM MODULE
Principal Features
Support for dial-up transmission protocols:
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V.34 – 2-wire full duplex modems operating at data signalling rates
of 33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800, 14400,
12000, 9600, 7200, 4800 and 2400 bps.
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Non-proprietary V.32 terbo – 2-wire full duplex modems operating
at data signalling rates of 19200, 16800, 14400, 12000, 9600, 7200
and 4800 bps.
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V.32bis – 2-wire full duplex modems operating at data signalling
rates of 14400, 12000, 9600, 7200 and 4800 bps.
V.32 – 2-wire full duplex modems operating at data signalling rates
of 9600 and 4800 bps.
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V.23 – 75/1200 bps operation.
V.22bis – 2400 bps full duplex operation.
V.22 and Bell 212A – 1200 bps full duplex 2-wire modem.
V.21 and Bell 103J – 300 bps modems.
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Support for leased line transmission protocols:
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V.34 – 2-wire or 4-wire full duplex modems operating at data
signalling rates of 33600, 31200, 28800, 26400, 24000, 21600, 19200,
16800, 14400, 12000, 9600, 7200, 4800 and 2400 bps.
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Non-proprietary V.32 terbo – 2-wire or 4-wire full duplex modems
operating at data signalling rates of 19200, 16800, 14400, 12000,
9600, 7200 and 4800 bps.
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V.32bis – 2-wire or 4-wire full duplex modems operating at data
signalling rates of 14400, 12000, 9600, 7200 and 4800 bps.
V.32 – 2-wire or 4-wire full duplex modems operating at data
signalling rates of 9600 and 4800 bps.
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2-wire PSTN backup of the Private line.
CCITT V.42bis or MNP Class 5 data compression.
Virtual error-free data passage using CCITT V.42 LAPM or MNP Level 4
error correction.
Introduction
1-3
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Asynchronous dial DTE data rates from 300 to 115200 bps.
Modem configuration changes using the DTE interface or throught the
Management Controller Module.
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Compatibility with the industry standard AT command set.
Storage of up to 20 telephone numbers in directory locations.
Dialling using AT commands, CCITT V.25bis commands or by raising
DTR on the Host to modem interface, or by data being sent to the DTE
interface.
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High-speed transmission using asynchronous or synchronous, or UNIX
devices over full duplex dial networks, and 2-wire or 4-wire lines.
Self testing facilities providing local and remote loopbacks, including
CCITT-compatible V.54.
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Five factory-set configurations and two user definable configurations.
Front panel LEDs to inform you of the current status of any of the three
modems.
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Easy to install, configure and support.
Implementation of V.32terbo
Support of the V.32terbo transmission protocol is included as a feature in
the modems. V.32terbo is a non-proprietary extension of the widely used
CCITT V.32bis standard which increases the maximum data signalling rate
from 14400 to 19200 bps over dial-up links or private lines.
Compatibility between V.32terbo and V.32bis is maintained in a similar
manner as it is between V.32bis and V.32, in that an identical training
sequence is used by each standard and that V.32terbo uses a subset of
the speeds available in V.32bis.
By default, each modem’s factory configurations enable V.32terbo to be
negotiated as the optimum data rate on any given link allowing a 33%
increase in line throughput, to 19200bps to be used wherever possible.
Where the quality of the line is not good enough to enable
transmission at 19200bps, an intermediate speed of 16800 bps can be
1-4
CHAPTER 1: TRIPLE MODEM MODULE
negotiated between modems, providing a 16.7% increase in speed
over that which can be negotiated using V.32bis. If the modem you are
calling is unable to operate at the same high speeds as your modem,
an optimum data transfer rate is negotiated between the two using the
default configuration settings.
When using the higher line speeds made available by V.32terbo, the
throughput rate can be increased further by using the modem’s error
correction and data compression facilities. Compression factors remain
virtually unaffected by the increase in line rate, thereby producing a real
improvement in data transmission times over those achieved using V.32bis.
Introduction
1-5
Typical Applications
The Triple Modem module is ideally suited for large central sites providing
access for remote users to central site services. In the example shown in
Figure 1-1 a large number of remote users connect to the central site’s
AccessBuilder 7000 and gain access to the corporate LAN and its facilities
through a terminal server (such as the 3Com CS3000/3100 series). The
advantage of this method is that all devices on the corporate LAN can be
accessed remotely by a large number of remote users.
Figure 1-1 Modem Connections To The Central Site.
1-6
CHAPTER 1: TRIPLE MODEM MODULE
Pack Contents Checklist
Before you install your Triple Modem Module, check the contents of
the box against the pack contents checklist below. If any of the items
have been damaged in transit or are missing, then contact the 3Com
reseller from whom the equipment was purchased.
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1 x Triple Modem Module front card.
1 x Triple Modem Module back card.
1 x AccessBuilder 7000 Triple Modem Module User Guide (This manual).
1 x AccessBuilder AT Command Reference guide.
1 x warranty registration card.
It is important that you save the box and protective packing material in
case you need to store, or transport your Triple Modem Module in the
future.
Registering Ownership of your Triple Modem Module
A warranty registration card is enclosed in the box with your
AccessBuilder 7000 Triple Modem Module. Please take a few moments
before commencing the installation to fill in the card and post it to us.
Pre-installation Requirements
1-7
Pre-installation Requirements
Before you install the Triple Modem Module into the AccessBuilder 7000
Access Concentrator chassis, check that the following requirements have
been met:
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The AccessBuilder 7000 Access Concentrator must already be fitted
with its power supply module(s) and the Management Controller
Module if required.
The rack unit into which you install the AccessBuilder 7000 must allow
for the door to be fully opened to remove existing modules or to install
new modules. During normal operation the door must remain closed.
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You should have DTE and telephone connection cables available and
have easy access to telephone connection points.
If you are using a terminal server for connection to your LAN, check
that this is installed and configured for operation.
1-8
CHAPTER 1: TRIPLE MODEM MODULE
INSTALLATION AND OPERATION
2
Overview
This chapter describes how to install the AccessBuilder 7000 Triple
Modem module into the AccessBuilder 7000 Access Concentrator
chassis, how to connect to your DTEs and PSTN lines and how to read
the LEDs on the module’s front panel.
Ensure you read the safety information at the front of this guide before
commencing installation of the AccessBuilder 7000 Triple Modem Module.
Check that you have met all the pre-requisites out-lined in Chapter 1
and that you have access to the phone lines to connect your modems.
2-2
CHAPTER 2: INSTALLATION AND OPERATION
Installing The Module
Before installing the module, read the Safety Information at the front of
this guide.
back card that both connect to the chassis’ backplane. It is recommended
that you install the module’s rear card into the chassis first.
The installation of the Triple Modem Module into the AccessBuilder
7000 chassis takes place in three distinct operations:
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Installing the front card.
Installing the rear card.
Connecting cables to the DTE and Line ports. See “Connecting the
Cables” on page 2-5 for more information about connecting to the ports.
swapable. It is not necessary to turn off the AccessBuilder 7000’s power
supply unit to install the Triple Modem Module. The Triple Modem
Module can be inserted any slot in the AccessBuilder 7000 chassis.
No connecting cables are supplied with the Triple Modem Module as
standard. For each of the three modems you need a PSTN line cable
and/or a 2/4-wire private line cable. You also need a cable to connect
your computer or DTE equipment to the DTE interface on the modem.
The male DTE connector conforms to the electrical characteristics of
V.24 as described in Appendix A.
CAUTION: At all times, take care not to touch any of the connectors or
components on the cards to avoid damage by static electricity. Handle
the cards by the handles or by their edges. Use an anti-static wrist strap
during installation if you have one available.
Installing The Module
2-3
Installing the Rear Card
Figure 2-1 Installing The Rear Card
1
2
Locate the rear slot equivalent to the front slot into which you will
install the front card.
Remove the metal blanking plate at the rear of the chassis and retain
the screws.
Retain the blanking plate. If you remove the module, the blanking plate
must be refitted to the chassis to aid the circulation of cooling air and
to prevent dust and debris entering the unit.
3
4
Insert the rear card with the RJ45 ports at the top of the card and slide
it home along the guide rails so that it connects with the backplane.
Secure the rear card into position using the screws from the blanking plate.
2-4
CHAPTER 2: INSTALLATION AND OPERATION
Installing the Front Card
Figure 2-2 Example of Installing A Front Card
1
2
3
4
Locate the front slot in the AccessBuilder 7000 chassis equivalent to the
rear slot in which you have already installed the rear card.
Insert the front card into the slot ensuring that it is centered along the
guide rails.
Use the module’s handles to push the card home into the chassis and
lock it into place.
Close and lock the chassis door.
To remove the card, unlatch the handles to free the card from the back
plane and pull the front card free from the chassis using the handles.
Installing The Module
2-5
Connecting the Cables
The ports on the rear panel are arranged in two groups.
Modem Lines 1-3
Each modem port has two connections:
1
2
3
Dial Line (1, 3 & 5) The upper RJ45 connection in each pair
connects to a normal dialled service, use this port to
connect your modem to the line. In some countries you may
need to use an adapter to connect to your PSTN service
provider’s socket.
4
5
6
If you use a two into one line adapter, a telephone
handset can be connected in parallel to your modem at
the PSTN outlet. In this case you must not lift the
telephone handset during data transmission. If it is lifted,
any noise in the surrounding area interferes with the data
and can cause corruption in the transferred data.
7
Private Line (2,4 & 6) The lower RJ45 connection in each
pair connects to a private line. Use this port to connect
your modem to the line. In some countries you may need
to use an adapter to connect to your PSTN service
provider’s socket.
8
9
DTE Ports 1- 3 (7,8 & 9)
Connect DTEs 1 through 3 to these ports using V.24
modem cable as described in Appendix A.
The DTE ports also allow direct access to the Triple Modem
Module’s management system using a PC or terminal. This
removes the need to access the Triple Modem Module
through the AccessBuilder 7000 Management Controller
Module.
For more information about configuring the module, see
the AccessBuilder 7000 AT Command Reference.
2-6
CHAPTER 2: INSTALLATION AND OPERATION
Front Panel LEDs
This section describes the Triple Modem Module’s LEDs. Most of the LEDs
can only be seen when the front door of the AccessBuilder 7000 chassis is
open. When the door is closed, only the PWR, ALARM, ALERT and TEST
LEDs can be seen. These LEDs show the status of the whole module.
The other status LEDs show information about one modem only. You can
select the modem by toggling the push button at the foot of the module.
ANS (Answer) Lights to show that the selected modem is configured to
automatically answer an incoming PSTN call. When an incoming call is
detected, this LED flashes in sequence with each ring pulse.
TERM (Terminal) Shows that a DTE is attached to the selected
modem’s DTE interface and that DTR is raised. It is normally used to
indicate that a call can be made or an incoming a call answered. The
modem may be configured to act in different ways on receipt of this
signal according to the AT&Dand AT&Mcommands. See AccessBuilder
7000 AT Command Reference for more information.
LINE (On Line) Indicates that the selected modem has seized the
telephone line.
CONN (Connect) Indicates that the selected modem has established a
valid connection to the remote device and is either negotiating the
error correction and data compression protocols to be used on the link
or it is ready to send and receive data. This LED does not indicate that
the DCD (Data Carrier Detect) signal is high on the DTE interface.
CORR (Correct) Indicates that an error correcting link has been made with
the remote modem. While using this facility, each time a re-send request is
initiated by the selected modem the LED flashes for a short period.
COMP (Compress) Indicates that the data compression facility is active
on the selected modem’s link giving you the maximum throughput
speed. During a call, this LED may go out when the modem is using
V.42bis compression if the modem determines that the link cannot
benefit from compression.
Front Panel LEDs
2-7
PWR (Power) When lit indicates that the module is receiving power from
the chassis’ backplane and that the power circuits are functioning correctly.
ALARM Lights to indicate that an event has occurred on one or more
of the modems which has been configured to raise an alarm. See the
AccessBuilder 7000 Access Concentrator User Guide for more information.
ALERT Lights to indicate that an event has occurred on one or more of
the modems which has been configured to raise an alert. See the
AccessBuilder 7000 Access Concentrator User Guide for more information.
TEST Indicates that one of the modems on the module is running a
test. This may have been initiated either by an attached DTE, via the
Management Controller Module or by a remote DTE to which the
modem has a communications link.
SEND Flashes on and off to indicate that the selected modem is
receiving data from the equipment attached to the DTE interface.
REC (Receive) Flashes on and off to indicate that the selected modem
is passing received data from the line to the DTE interface.
CH 1 (Modem 1) Shows that Modem 1 is selected and that the LEDs show
the status of this modem.
CH 2 (Modem 2 Shows that Modem 2 is selected and that the LEDs show
the status of this modem.
CH 3 (Modem 3) Shows that Modem 3 is selected and that the LEDs show
the status of this modem.
Push Button Selects the modem whose status is shown by the front
panel LEDs. Toggle this button until the required Modem LED is lit.
2-8
CHAPTER 2: INSTALLATION AND OPERATION
TROUBLESHOOTING
3
Troubleshooting Guide
In this section we discuss the basic problems that can occur when using
your modem. If you are having data communication difficulties such as
periodic character loss, random errors, or constant format errors: use the
loopback tests described in AccessBuilder 7000 AT Command Reference.
With these tests you can usually isolate the fault in your system by using
a process of elimination. If a problem continues to occur, contact your
supplier for assistance.
Modem Health
POWER LED does not light
Make sure that the front and rear cards are pushed fully home, and that
the rack enclosure is powered ON.
A problem is suspected after the power-up self-test
Initiate a local analogue loopback with a pattern test. If the modem
consistently registers errors, contact your modem supplier.
If the modem passes these tests and you still have a problem, it is
probably not with your modem.
3-2
CHAPTER 3: TROUBLESHOOTING
Modem - DTE Connection
Modem does not accept or echo back AT commands
Check that the cable between the serial port of the DTE and the modem
is a standard RS232 cable. If the cable is bad, replace it. (Null modem
cables, also known as cross-over cables, do not work in this application).
A limited number of dumb terminals require DCD before they can talk
to the modem. If this is the case you have to use a breakout box to
raise DCD to the terminal. You can then configure the modems to force
DCD using the AT&C0command.
Check that the character echo command is enabled using the ATE
command.
Check that the DTE dialler type configuration option is set to AT. Refer
to the AT&Mor AT&Qcommand description.
Check that the response codes configuration option is enabled using
the ATQcommand.
Make sure that all AT commands are terminated with a carriage return.
Check that the ASCII value of a carriage return matches what is used by
the DTE and the modem (defined using S-Register S3).
Check that the DTE and modem are using a compatible character format.
Valid formats include 8 data bits with no parity, or 7 data bits with even,
odd, mark or space parity.
Check that the DTE’s data rate is supported by the modem.
Troubleshooting Guide
3-3
Modem - Telephone Line Connection
Connection Problems in Answering a Call
Modem does not receive a dial tone
Attach a telephone direct to the wall outlet to check if a dial tone exists.
Make sure the telephone line is connected to the appropriate modem’s
rear panel PSTN jack.
Modem does not go off-hook and answer an incoming call
Check that the auto-answer ring count configuration option
(S-Register 0) is set to a value other than 0.
Check that the DTE is providing DTR to the modem.
If the DTE does not provide DTR to the modem, check that the modem’s
DTR signalling configuration option is set to ignore the state of DTR.
Check that all cables are attached to the right connectors at the rear of
the modem.
Modem goes off-hook, answers, but does not connect
Perform a local analogue loop test and check that data entered at the
DTE is echoed back to the DTE.
Check that the originating modem’s configuration is compatible with
your receiving modem’s configuration.
Check that the originating modem recognizes your modem’s answer tone.
Check that the originating modem supports your modem’s operating
protocols.
Force your modem to operate using the same transmission protocol as
the originating modem to see if they connect.
3-4
CHAPTER 3: TROUBLESHOOTING
Connection Problems When Originating a Call
Modem fails to go off-hook and originate a call
Check that the modem’s configuration enables either AT dialling or
V.25bis dialling. Note: A modem configured to accept AT commands
cannot accept V.25bis commands, and vice versa.
If using DTR dialling, check the telephone number stored in directory
location 1, and check that the DTE is raising DTR from OFF to ON to
initiate a dial.
If using V.25bis asynchronous dialling, check that the correct character
format is set to 7 data bits with even parity and 1 stop bit, and the
carriage return and line feed are used as command terminators.
If using V.25bis bisynchronous dialling, check that the correct character
format uses two synchronous control characters and a start-of-text
control character before the text block, and an end-of-text control
character after it.
If using V.25bis HDLC, check that the correct character format uses flag,
address and control characters before the text block, and a frame
sequence check and flag after the text block.
Modem dials but does not connect
If the modem is operating behind a PBX, check if a 9 and comma are
needed before the telephone number.
Check whether tone or pulse dialling is needed.
Check if one modem is configured for error correction or disconnect,
and the other modem is configured for no error correction. Try
initiating the call in buffer mode.
If both modems use V.32bis or V.32, set the modem’s V.32bis training
configuration option to Long.
Troubleshooting Guide
3-5
Intermittent disconnects, high error rates, or excessive
retransmissions
Perform a remote digital loop test as described in the AccessBuilder
7000 AT Command Reference.
Modem establishes and disconnects a call
You may have a poor telephone line connection. Disconnect and dial
again.
The remote modem may have encountered an error correction
disconnect, where the modem is configured to establish a call using error
correction. If the modem cannot negotiate error correction, then a
disconnect occurs.
The remote modem may be in a forced error correction mode
(disconnect if there is no error control). Reconfigure your modem to
V.42/MNP or buffer correction and try again.
Perform a local analogue loop test.
3-6
CHAPTER 3: TROUBLESHOOTING
On-line Operation
Data is scrambled
Check that the character format (data bits, parity, and stop bits) is set to
the same value in both modems.
Missing data during a transfer
Check that you are using the same method of flow control for both the
modem and the DTE.
If using XON/XOFF flow control, check that the modem’s parity matches
the DTE’s parity.
Private-line Operation
Modems do not train-up on private lines
Check that the correct cabling is used for your application.
Check that one modem is configured for answer mode and the other is
configured for originate mode.
Check that both modems are using the same modulation scheme.
Dial Backup Operation
Modems do not establish a PSTN link when the Private line fails
Check that the communicating modems are configured to support dial
backup, as described in the AccessBuilder 7000 AT Command Reference.
Check that one modem is configured to initiate the backup (i.e. is the
master modem, and has the backup telephone number stored in its
directory location 8) and the other modem is configured to be a slave
(its directory location 8 is empty).
Check that both modems are using the same modulation scheme over
their PSTN line.
MODEM SPECIFICATION AND
INTERFACE PIN ASSIGNMENTS
A
Transmitter / Receiver Specifications
Modulation
CCITT V.34 (33600, 31200, 28800, 26400, 24000, 21600, 19200, 16800,
14400, 12000, 9600, 7200, 4800, 2400 bps)
Non-proprietary V.32terbo (19200, 16800, 14400, 12000, 9600, 7200,
4800 bps)
CCITT V.32bis (14400, 12000, 9600, 7200, 4800 bps)
CCITT V.32 (9600, 4800 bps)
CCITT V.22bis (2400 bps)
CCITT V.22 (1200 bps)
CCITT V.21 (300 bps)
Bell 212A (1200 bps)
Bell 103J (300 bps)
Operation
2-wire or 4-wire synchronous/asynchronous private line, or 2-wire
PSTN operation.
Output level
Selectable 0 dBm to -15 dBm. 600 ohms impedance. (UK versions set to
-9 dBm for PSTN operation or -13 dBm for private wire.)
A-2
APPENDIX A: MODEM SPECIFICATION AND INTERFACE PIN ASSIGNMENTS
Data Input
Serial binary. Complies with CCITT V.28. Accepts levels 3 volts to 25
volts. (+)= space (-)= mark. Single wire ground return. 3000 to 7000
ohms load.
Data Output
Serial binary. Complies with CCITT V.28 12 volts nominal. Output
impedance 300 ohms.
Synchronization
RTS/CTS delay dependent on modulation format.
Equalizer
Automatic adaptive equalizer.
Error correction
V.42 LAPM and MNP4.
Data compression
V.42bis and MNP5.
Autodial - Autoanswer
Method
Pulse dial. 10 pps rate. Make period 33 msec. Break period 67 msec (UK
version). Interdigit period 800msec. Tone dial. On time 85 msec. ID time
85 msec. Duty cycle 50%.
Line Interface
600 ohm impedance. Bell tinkle suppression provided. Old and new
dial tone detection. Secondary dial tone detection for PABX use.
Progress tones and answer tone detection.
Physical Description
A-3
Protocols
Extended AT command set. Non-volatile memory. 5 preset factory, 2
user defined configurations and one power-up configuration. 20
stored telephone numbers. AT or V.25bis asynchronous, bisynchronous
and HDLC synchronous commands are entered via the DTE interface.
ASCII or EBCDIC character set used in V.25bis command mode.
Autoanswer
CCITT V.25 compliant.
Busy
Busy out via AT command or DTR.
Disconnect
Call cleared selectable on loss of DTR; and/or no carrier for n seconds;
and/or no data for n seconds; and/or a disconnect request is received
from the remote modem in error correction.
Test Functions
Local analogue loop, local digital loop, or remote digital loop available
using AT commands.
Physical Description
Power
16V ac, 47 to 63 Hz, 1A max. Typical power consumption 11 Watts.
Environment
Temperature 0 to 40 degrees centigrade operating. -50 to 70 degrees
centigrade storage.
Relative humidity 5% to 95% non-condensing.
Altitude to 3000 meters.
A-4
APPENDIX A: MODEM SPECIFICATION AND INTERFACE PIN ASSIGNMENTS
Approvals Information
This product complies with the electro-magnetic compatibility (EMC)
requirements of EN 55022 Class A and EN 50082 (susceptibility).
The product carries the CE certification mark to indicate conformance
with the following EU directives:
■
■
■
LVD (Low Voltage Directive (Safety) 73/23/EEC.
EMC (Electro Magnetic Compatibility) Directive 89/336/EEC.
TTE (Telecommunication Terminal Equipment) Directive 91/263/EEC.
This product also meets the safety requirements of EN41003 and EN60950.
See also the FCC and CSA statements at the back of this guide.
General Approvals Requirements
This section pertains to the approval of the modems, and to your country’s
approvals board requirements and notices for use of these modems. Users
of this module should pay particular attention to this information. This unit
is approved for connection to the telecommunications systems specified
in the instructions for use, subject to the conditions set out in them.
Each modem is suitable for connection to the general switched telephone
network (GSTN/PSTN) and extensions on compatible PABXs. It is also
suitable for use on point-to-point private circuits, omnibus or multipoint
circuits, using two or four wire termination (provided by Approved
Telecommunication Operators), or to a relevant branch system.
If any other apparatus, including cable or wiring, is to be connected
between the apparatus and the point of connection to a 2-wire or
4-wire speech band circuit, then all that other apparatus shall conform
to the following:
■
The overall transmission characteristics of all that other apparatus shall be
such as to introduce no material effect upon the electrical conditions
presented to one another by the apparatus and the digital circuit.
Approvals Information
A-5
■
All the other apparatus shall comprise only:
■
Apparatus approved (see note) for the purpose of connection
between the apparatus and the digital circuit; and
■
Cable or wiring complying with a code of practice for the
installation of apparatus covered by this standard or such other
requirements as may be applicable.
Such apparatus may have been approved subject to limitations on its
use.
This modem is suitable for use on telephone lines provided with
loop-disconnect or multi-frequency (MF) dialling facilities.
This modem is suitable for household, office and similar indoor use, but is
not suitable for use on an extension to a payphone, or a 1+1 carrier system.
This unit may be used on circuits with CEPT L1 signalling at a nominal
frequency of 2280 Hz. It does not require signalling or otherwise
employ the frequency range 0 Hz to 200 Hz and there is no
requirement for DC from the telephone line for correct operation.
This unit causes a line voltage drop of 0.2 V at a line current of 40 mA
Interference and Safety Requirements
Radio frequency interference may be caused by incorrect operation or
inadequate maintenance of this equipment. This unit is intended for
use with screened digital cables.
If any of your apparatus is not operating correctly, you should
immediately remove it from the telephone line as this may harm the
telephone network (GSTN).
The approval of this unit for connection to GSTN or private speech
band circuits is invalid if the apparatus is subject to modification in any
material way not authorized or if it is used with or connected to
internal software which has not been formally accepted.
A-6
APPENDIX A: MODEM SPECIFICATION AND INTERFACE PIN ASSIGNMENTS
CAUTION: Danger of explosion if the battery is incorrectly replaced.
Replace only with the same or equivalent type of battery as specified
by the manufacturer. A used battery must be disposed of in accordance
with the manufacturer’s instructions.
PBX and PABX Application
This unit has been approved for use of the following facilities.
■
■
■
■
■
■
■
■
■
■
■
■
Loop-disconnect and multi-frequency signalling.
Storage of telephone numbers for retrieval by a predetermined code.
Detection of initial proceed indication.
Detection of secondary proceed indication.
Operation in the absence of proceed indication.
Automatic dialling facilities.
Tone detection, for example, ring tone, busy tone.
Automatic answering of incoming calls.
Automatic clearing from call originating end.
Call progress monitor.
Series connection (via optional cable).
Modem.
Any other usage will invalidate the approval of the apparatus if as a
result it then ceases to conform to the standards against which
approval was granted.
This unit is only approved for compatible PBXs. The supplier of your
unit should be consulted for an up-to-date list of PBXs with which this
unit is compatible.
There is no guarantee of correct working in all circumstances. Any
difficulty should be referred to the supplier of the unit.
This unit is suitable for connection to PBXs which return secondary
proceed indication.
Approvals Information
A-7
Ringer Equivalence
REN is a guide to the maximum number of apparatus (for example,
telephones) that can be simultaneously connected to one telephone
line. The REN value of each apparatus is added together and must not
exceed 4. Unless otherwise marked, a telephone can be assumed to
have a REN of 1.0. Each modem on this unit has a ringer equivalence
number (REN) of 4.0.
A-8
APPENDIX A: MODEM SPECIFICATION AND INTERFACE PIN ASSIGNMENTS
DTE Port Pin Assignments
Each modem is equipped with a single serial port marked DTE, which
can be used to enter asynchronous AT or V.25bis commands, and pass
asynchronous or synchronous user data. This is a female 26-pin V.24
connector and can be used with X.21/V.11, v.24/V.28 or V.35/V.36
signalling. The cable pin-outs for each type of cable are shown below.
X.21/V.11
The DTE port terminates with a 26-way miniature SCSI connector. The port
can be configured to support V.11 signalling characteristics. The DTE port
connecting cable is not supplied with the module. The following signalling
characteristics should be observed when purchasing or fabricating a
suitable cable.
DTE Port Pin Assignments
A-9
V.24/V.28
The DTE port terminates with a 26-way miniature SCSI connector.
The port can be configured to support V.24 or V.28 signalling
characteristics. The DTE port connecting cable is not supplied with the
module. The following signalling characteristics should be observed
when purchasing or fabricating a suitable cable.
A-10
APPENDIX A: MODEM SPECIFICATION AND INTERFACE PIN ASSIGNMENTS
V.35/V.36
The DTE port terminates with a 26-way miniature SCSI connector.
The port can be configured to support V.36 signalling characteristics.
The DTE port connecting cable is not supplied with the module. The
following signalling characteristics should be observed when
purchasing or fabricating a suitable cable.
PSTN Port Cable Pin Assignments
A-11
PSTN Port Cable Pin Assignments
Each modem on the communications card is equipped with a single
PSTN line port, which is accessed via the appropriate DIAL LINE socket
on the card’s interface module (refer to the rear panel diagram in
Section 1.2 for an exact reference of which socket services which
modem on the communications card). This is an RJ11 type socket, that
would typically be connected to a PSTN telephone wall socket using a
cable conforming to the wiring diagram shown below:
A-12
APPENDIX A: MODEM SPECIFICATION AND INTERFACE PIN ASSIGNMENTS
Private Line Port Cable Pin Assignments
Each modem on the communications card is equipped with a single
Private line port supporting either a 2- or 4-wire connection, which is
accessed via the appropriate PRIVATE LINE socket on the card’s interface
module (refer to the rear panel diagram in Section 1.2 for an exact
reference of which socket services which modem on the
communications card). This is an RJ11 type socket, that would typically
be connected to a 2- or 4-wire private line outlet using a cable
conforming to the wiring diagram shown below:
TECHNICAL SUPPORT
B
3Com provides easy access to technical support information through
the variety of services described in this appendix.
On-line Technical Services
3Com offers worldwide product support seven days a week, 24 hours a
day, through the following on-line systems:
3Com Bulletin Board Service (3ComBBS)
World Wide Web site
■
■
3Com Bulletin Board Service
3ComBBS contains patches, software, and drivers for all 3Com products,
as well as technical articles. This service is available via modem or ISDN
seven days a week, 24 hours a day.
Access by Modem
To reach the service by modem, set your modem to 8 data bits, no
parity, and 1 stop bit.
B-2
APPENDIX B: TECHNICAL SUPPORT
Call the telephone number nearest you:
Country
Australia
France
Data Rate
Telephone Number
(61) (2) 9955 2073
(33) (1) 69 86 69 54
up to 14400 bps
up to 14400 bps
up to 9600 bps
Germany
(49) (89) 627 32 188 or (49) (89) 627 32
189
Hong Kong
up to 14400 bps
(852) 2537 5608
(39) (2) 273 00680
(81) (3) 3345 7266
(65) 534 5693
Italy (fee required) up to 14400 bps
Japan
Singapore
Taiwan
U.K.
up to 14400 bps
up to 14400 bps
up to 14400 bps
up to 28800 bps
up to 28800 bps
(886) (2) 377 5838
(44) (1442) 278278
(1) (408) 980 8204
U.S.
Access by ISDN
ISDN users can dial-in to 3ComBBS using a digital modem for fast
access up to 56 Kbps. To access 3ComBBS using ISDN, dial the
following number:
(1) (408) 654-2703
World Wide Web Site
Access the latest networking information on 3Com’s World Wide Web
site by entering our URL into your Internet browser:
This service features news and information about 3Com products,
customer service and support, 3Com’s latest news releases, selected
articles from 3TECH™ (3Com’s award-winning technical journal) and
more.
Support from Your Network Supplier
B-3
Support from Your Network Supplier
If additional assistance is required, 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.
When you contact your network supplier for assistance, have the
following information ready:
■
■
■
Diagnostic error messages
A list of system hardware and software, including revision levels
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.
B-4
APPENDIX B: TECHNICAL SUPPORT
Support from 3Com
If you are unable to receive support from your network supplier,
technical support contracts are available from 3Com.
In the U.S. and Canada, call (800) 876-3266 for customer service.
If you are outside the U.S. and Canada, contact your local 3Com sales
Country
Telephone Number
Country
Telephone Number
Australia
(Sydney)
(61) (2) 959 3020
Japan
(81) (3) 33457251
(Melbourne) (61) (3) 653 9515
Mexico
(525) 531 0591
06 0227788
Belgium*
0800 71429
Netherlands*
Norway*
Singapore
South Africa
Spain*
Brazil
(55) (11) 546 0869
(905) 882 9964
800 17309
800 13376
Canada
(65) 538 9368
(27) (11) 803 7404
900 983125
Denmark*
Finland*
France*
0800 113153
05 917959
Sweden*
Taiwan
020 795482
Germany*
Hong Kong
0130 821502
(852) 868 9111
(886) (2) 577 4352
(971) (4) 349049
United Arab
Emirates
Ireland*
Italy*
1 800 553117
1678 79489
U.K.*
U.S.
0800 966197
(1) (408) 492 1790
* These numbers are toll-free.
Returning Products for Repair
B-5
Returning Products for Repair
A product sent directly to 3Com for repair must first be assigned a
Return Materials Authorization (RMA) number. A product sent to 3Com
without an RMA number will be returned to the sender unopened, at
the sender’s expense.
To obtain an RMA number, call or fax:
Country
Telephone Number
Fax Number
U.S. and Canada
Europe
(800) 876 3266, option 2
31 30 60 29900, option 5
(408) 764 7120
(44) (1442) 275822
(1) (408) 764 7290
Outside Europe, U.S., and Canada (1) (408) 492 1790
11/29/95
B-6
APPENDIX B: TECHNICAL SUPPORT
INDEX
Numerics
3Com Bulletin Board Service (3ComBBS) D-1
3Com sales offices D-4
installation 2-2
front card 2-4
prerequisites 1-7
A
ALARM LED 2-7
ALERT LED 2-7
ANS LED 2-6
B
bulletin board service D-1
N
network supplier support D-3
C
cable pin-outs A-8
CH 1 LED 2-7
O
CH 2 LED 2-7
CH 3 LED 2-7
on-line technical services D-1
COMP LED 2-6
CONN LED 2-6
connecting cables 2-5
CORR LED 2-6
P
pack contents 1-6
ports 2-5
pre-installation requirements 1-7
PSTN line ports 2-5
push button 2-7
PWR LED 2-7
D
DTE ports 2-5
F
R
features 1-2
rear card installation 2-3
REC LED 2-7
front card installation 2-4
returning products for repair D-5
2
INDEX
S
SEND LED 2-7
T
technical information A-1
technical support D-1
TERM LED 2-6
TEST LED 2-7
Triple Modem
features 1-2
overview 1-1
typical applications 1-5
troubleshooting 3-1
typical applications 1-5
V
V.32terbo 1-3
LIMITED WARRANTY
HARDWARE: 3Com warrants its hardware products to be free from defects in workmanship and materials,
under normal use and service, for the following lengths of time from the date of purchase from 3Com or its
Authorized Reseller:
Internetworking products
One year
Network adapters
Lifetime
Ethernet stackable hubs and unmanaged Ethernet fixed port repeaters
Lifetime*
(One year if not registered)
*Power supply and fans in these stackable hubs and unmanaged repeaters One year
Other hardware products
Spare parts and spares kits
One year
90 days
If a product does not operate as warranted above during the applicable warranty period, 3Com shall, at its
option and expense, repair the defective product or part, deliver to Customer an equivalent product or part to
replace the defective item, or 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. Any replaced or repaired product or part has a ninety (90) day warranty or the remainder of the
initial warranty period, whichever is longer.
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.
SOFTWARE: 3Com warrants that the software programs licensed from it will perform in substantial
conformance to the program specifications therefor 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 with respect to this express warranty shall be
(at 3Com's discretion) to refund the purchase price paid by Customer for any defective software products, or to
replace any defective media with software which substantially conforms to 3Com's applicable published
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 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.
STANDARD WARRANTY SERVICE: Standard warranty service for hardware products may be obtained by
delivering the defective product, accompanied by a copy of the dated proof of purchase, to 3Com's Corporate
Service Center or to an Authorized 3Com Service Center during the applicable warranty period. Standard
warranty service for software products may be obtained by telephoning 3Com's Corporate Service Center or an
Authorized 3Com Service Center, within the warranty period. Products returned to 3Com's Corporate Service
Center must be pre-authorized by 3Com with a Return Material Authorization (RMA) number marked on the
outside of the package, and sent prepaid, insured, and packaged appropriately for safe shipment. The repaired
or replaced item will be shipped to Customer, at 3Com's expense, not later than thirty (30) days after receipt of
the defective product by 3Com.
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, AND SATISFACTORY QUALITY. 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.
3COM SHALL NOT BE LIABLE UNDER THIS WARRANTY IF ITS TESTING AND EXAMINATION DISCLOSE THAT THE
ALLEGED DEFECT 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 REPAIR OR
MODIFY, OR ANY OTHER CAUSE BEYOND THE RANGE OF THE INTENDED USE, OR BY ACCIDENT, FIRE,
LIGHTNING, OR OTHER HAZARD.
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.
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, so the above
limitations and exclusions may be limited in their application to you. 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.
3Com Corporation
5400 Bayfront Plaza
Santa Clara, CA 95052-8145
(408) 764-5000
3/18/96
FCC CLASS A VERIFICATION STATEMENT
This equipment has been tested with a class A computing device and has been found to comply with part 15
of FCC Rules. Operation in a residential area may cause unacceptable interference to radio and TV receptions
requiring the operator to take whatever steps are necessary to correct the interference.
CSA Statement
This digital apparatus does not exceed the Class A limits for radio noise emissions from digital apparatus as set
out in the interference-causing equipment standard entitled “Digital Apparatus”, ICES-003 of the Department of
Communications.
Cet appareil numérique respecte les limites de bruits radioélectriques applicables aux appareils numériques de
Classe A prescrites dans la norme sur le matériel brouilleur: “Appareils Numériques”, NMB-003 édictée par le
ministre des Communications.
European Statement
This is a Class A product. In a domestic environment this product may cause radio interference, in which case
the user may be required to take adequate measures.
Information To The User
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.
If necessary, the user should consult the dealer or an experienced radio/television technician for additional
suggestions. The user may find the following booklet prepared by the Federal Communications Commission
helpful:
How to Identify and Resolve Radio-TV Interference Problems
This booklet is available from the U.S. Government Printing Office, Washington, DC 20402, Stock No.
004-000-00345-4.
In order to meet FCC emissions limits, this equipment must be used only with cables which comply with IEEE
802.3.
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