Cabletron Systems SEH-34, SEH-24, SEH-32 User Manual
SEH-22, SEH-24, SEH-32, AND SEH-34
The Complete Networking Solution™
10BASE-T STACKABLE HUB
USER’S GUIDE
CABLETRON SYSTEMS, P. O. Box 5005, Rochester, NH 03866-5005
NOTICE
per
NOTICE
Cabletron Systems reserves the right to make changes in specifications and other
information contained in this document without prior notice. The reader should in all
cases consult Cabletron Systems to determine whether any such changes have been
made.
The hardware, firmware, or software described in this manual is subject to change
without notice.
IN NO EVENT SHALL CABLETRON SYSTEMS BE LIABLE FOR ANY INCIDENTAL,
INDIRECT, SPECIAL, OR CONSEQUENTIAL DAMAGES WHATSOEVER
(INCLUDING BUT NOT LIMITED TO LOST PROFITS) ARISING OUT OF OR
RELATED TO THIS MANUAL OR THE INFORMATION CONTAINED IN IT, EVEN
IF CABLETRON SYSTEMS HAS BEEN ADVISED OF, KNOWN, OR SHOULD HAVE
KNOWN, THE POSSIBILITY OF SUCH DAMAGES.
© Copyright February 1994 by:
Cabletron Systems, Inc.
P.O. Box 5005, Rochester, NH 03867-0505
All Rights Reserved
Printed in the United States of America
Order Number: 9030903-01 February 94
SPECTRUM®,
MicroMMAC™ are trademarks of Cabletron Systems, Inc.
IBM
is a registered trademark of International Business Machines Corporation.
CompuServe
DEC, VT200
Ethernet
Windows
LANVIEW®,
is a registered trademark of CompuServe, Inc.
, and
VT300
is a trademark of Xerox Corporation.
is a registered trademark of Microsoft Corporation.
Remote LANVIEW® ,
are trademarks of Digital Equipment Corporation.
Printed On
HubSTACK™ , and
Recycled Pa
i
NOTICE
FCC NOTICE
This device complies with Part 15 of the FCC rules. Operation is subject to the following
two conditions: (1) this device may not cause harmful interference, and (2) this device
must accept any interference received, including interference that may cause undesired
operation.
NOTE: This equipment has been tested and found to comply with the limits for a Class
A digital device, pursuant to Part 15 of the FCC rules. These limits are designed to
provide reasonable protection against harmful interference when the equipment is
operated in a commercial environment. This equipment uses, generates, and can radiate
radio frequency energy and if not installed in accordance with the operator’s manual,
may cause harmful interference to radio communications. Operation of this equipment
in a residential area is likely to cause interference in which case the user will be required
to correct the interference at his own expense.
WARNING: Changes or modifications made to this device which are not expressly
approved by the party responsible for compliance could void the user’s authority to
operate the equipment.
DOC NOTICE
This digital apparatus does not exceed the Class A limits for radio noise emissions from
digital apparatus set out in the Radio Interference Regulations of the Canadian
Department of Communications.
Le présent appareil numérique n’émet pas de bruits radioélectriques dépassant les
limites applicables aux appareils numériques de la class A prescrites dans le Règlement
sur le brouillage radioélectrique édicté par le ministère des Communications du Canada.
ii
NOTICE
CABLETRON SYSTEMS, INC.
PROGRAM LICENSE AGREEMENT
IMPORTANT: Before utilizing this product, carefully read this License Agreement.
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(“Cabletron”) that sets forth your rights and obligations with respect to the Cabletron
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CABLETRON SOFTWARE PROGRAM LICENSE
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2. OTHER RESTRICTIONS. You may not reverse engineer, decompile, or
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3. APPLICABLE LAW. This License Agreement shall be interpreted and governed
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the personal jurisdiction and venue of the New Hampshire courts.
iii
NOTICE
EXCLUSION OF WARRANTY
AND DISCLAIMER OF LIABILITY
1. EXCLUSION OF WARRANTY. Except as may be specifically provided by
Cabletron in writing, Cabletron makes no warranty, expressed or implied,
concerning the Program (including Its documentation and media).
CABLETRON DISCLAIMS ALL WARRANTIES, OTHER THAN THOSE
SUPPLIED TO YOU BY CABLETRON IN WRITING, EITHER EXPRESS OR
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WHATSOEVER (INCLUDING, WITHOUT LIMITATION, DAMAGES FOR LOSS
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OR LIMITATION OF IMPLIED WARRANTEES IN SOME INSTANCES THE
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UNITED STATES GOVERNMENT
RESTRICTED RIGHTS
The enclosed product (a) was developed solely at private expense; (b) contains “restricted
computer software” submitted with restricted rights in accordance with Section 5222719 (a) through (d) of the Commercial Computer Software - Restricted Rights Clause and
its successors, and (c) in all respects is proprietary data belonging to Cabletron and/or its
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For Department of Defense units, the product is licensed with “Restricted Rights” as
defined in the DoD Supplement to the Federal Acquisition Regulations, Section 52.2277013 (c) (1) (ii) and its successors, and use, duplication, disclosure by the Government is
subject to restrictions as set forth in subparagraph (c) (1) (ii) of the Rights in Technical
Data and Computer Software clause at 252.227-7013. Cabletron Systems, Inc., 35
Industrial Way. Rochester, New Hampshire 03867
iv
CONTENTS
TABLE OF CONTENTS
APPENDIX A TABLE OF CONTENTS v
CHAPTER 1 INTRODUCTION
1.1 USING THIS MANUAL............................................................1-1
1.2 GETTING HELP........................................................................1-2
1.3 SEH OVERVIEW.......................................................................1-2
1.4 SEH FEATURES .......................................................................1-3
1.5 STACKABLE CAPABILITIES..................................................1-4
1.6 OPTIONAL FEATURES ........................................................... 1-4
1.7 RELATED MANUALS ..............................................................1-5
CHAPTER 2 INSTALLATION
REQUIREMENTS/SPECIFICATIONS
2.1 CABLE SPECIFICATIONS.......................................................2-1
2.1.1 HubSTACK Interconnect Cable Requirements...........2-1
2.1.2 UTP and STP Cable Specifications for the Network Ports
and EPIM-T Module......................................................2-2
2.1.3 Multimode Fiber Optic Cable Specifications for the
EPIM-F1 and EPIM-F2 Modules ................................. 2-4
2.1.4 Single Mode Fiber Optic Cable Specifications for
the EPIM-F3 Module .................................................... 2-5
2.1.5 Thin-net Network Requirements for the EPIM-C Mod-
ule 2-6
2.1.6 AUI Cable Requirements for the EPIM-A and EPIM-X
Modules..........................................................................2-7
2.2 NETWORK PORT SPECIFICATIONS ....................................2-7
2.2.1 SEH-22 and SEH-24 Network Port Specifications......2-8
2.2.2 SEH-32 and SEH-34 Network Port Specifications......2-8
2.3 EPIM SPECIFICATIONS .......................................................2-10
2.3.1 EPIM-T........................................................................2-10
2.3.2
2.3.3 EPIM-F3......................................................................2-12
2.3.4 EPIM-C........................................................................ 2-14
2.3.5 EPIM-A and EPIM-X (AUI Port)................................2-15
2.4 TRANSCEIVER REQUIREMENTS.......................................2-16
2.5 OPERATING SPECIFICATIONS........................................... 2-16
EPIM-F1/F2.................................................................2-11
v
CONTENTS
CHAPTER 3 INSTALLATION
3.1 UNPACKING THE SEH............................................................3-1
3.2 INSTALLING THE SEH............................................................3-1
3.2.1 Stacking the SEH..........................................................3-2
3.2.2 Attaching the Strain Relief Bracket.............................3-4
3.2.3 Rack Mounting the SEH...............................................3-5
3.2.4 Wall Mounting the SEH................................................3-6
3.2.5 Free-Standing Installation............................................3-7
3.3 CONNECTING THE SEH TO THE POWER SOURCE..........3-8
CHAPTER 4 CONNECTING TO THE NETWORK
4.1 CONNECTING THE SEH TO THE NETWORK .....................4-1
4.1.1 Connecting Network Ports SEH-22 and SEH-24.........4-1
4.1.2 Connecting Network Ports SEH-32 and SEH-34.........4-3
4.1.3 Connecting a UTP Segment to an EPIM-T..................4-4
4.1.4 Connecting a Fiber Optic Link Segment to an EPIM-F1,
EPIM-F2, or EPIM-F34-5
4.1.5 Connecting a Thin-Net Segment to an EPIM-C ..........4-8
4.1.6 Connecting an AUI Cable to an EPIM-A ...................4-10
4.1.7 Connecting an AUI Cable to an EPIM-X....................4-11
4.2 FINISHING THE INSTALLATION........................................4-12
CHAPTER 5 TROUBLESHOOTING
5.1 INSTALLATION CHECK-OUT ................................................5-1
5.2 USING LANVIEW......................................................................5-2
APPENDIX B TWISTED PAIR WIRING TABLES A-1
vi
CHAPTER 1
INTRODUCTION
INTRODUCTION
Welcome to the Cabletron Systems
SEH-34 10BASE-T Stackable Hub User’s Guide
explains installation instructions and provides reference information
for the SEH-22, 24, 32, and 34.
Note
: The term SEH (Stackable Ethernet Hub) is used throughout this
manual when describing features and functions that are common to the
SEH-22, 24, 32, and 34.
1.1 USING THIS MANUAL
Read through this manual completely to familiarize yourself with its
content and to gain an understanding of the features and capabilities
of the SEH. A general working knowledge of Ethernet and IEEE 802.3
type data communications networks and their physical layer
components will be helpful when installing the SEH.
Chapter 1,
describes SEH features, and concludes with a list of related manuals.
Chapter 2,
installation requirements, network guidelines, and SEH operating
specifications.
Introduction
Installation Requirements/Specifications
, outlines the contents of this manual, briefly
SEH-22, SEH-24, SEH-32, and
. This manual
, describes
Chapter 3,
as a stackable or stand-alone hub.
Chapter 4,
SEH to the network using the various media types.
Chapter 5,
LEDs to troubleshoot network problems.
Appendix A,
for Punch Down Block applications.
Installation
Connecting to the Network
Troubleshooting,
Twisted Pair Wiring Tables
, contains instructions for installing your SEH
describes how to use the LANVIEW
, explains how to connect the
, contains wiring pinouts
Page 1-1
INTRODUCTION
1.2 GETTING HELP
If you need additional support related to the Cabletron Systems SEH,
or if you have any questions, comments, or suggestions concerning this
manual, contact Cabletron Systems Technical Support:
By phone......................... (603) 332-9400
Monday-Friday; 8am - 8pm EST
By CompuServe®............ GO CTRON from any ! prompt
By Internet mail............. support@ctron.com
1.3 SEH OVERVIEW
The 10BASE-T SEH is a non-intelligent repeating hub that provides
front panel ports for network connections and rear panel HubSTACK
Interconnect Bus ports for stackable connections.
HubSTACK 10BASE-T HUB WITH LANVIEW®
SEH-24
PWR
MGMT
CLN
RCV
LNK
RCV
LNK
24 23 22 21 20 19 18 17 16 15 14 13
12 11 10 9 8 7 6 5 4 3 2 1
SEH-24 10BASE-T HUB WITH LANVIEW®
OUT
SEH INTERCONNECT
HubSTACK 10BASE-T HUB WITH LANVIEW®
SEH-34
PWR
MGMT
CLN
RCV
LNK
RCV
LNK
24 23 22 21 20 19 18 17 16 15 14 13
12 11 10 9 8 7 6 5 4 3 2 1
SEH-34 10BASE-T HUB WITH LANVIEW®
OUT
SEH INTERCONNECT
Figure 1-1. The SEH-24 and SEH-34
E
2
24X 23X 22X 21X 20X 19X
E
1
12X 11X 10X 9X 8X 7X
IN
E
2
24X 13X
E
12X 1X
1
IN
18X 17X 16X 15X 14X 13X
6X 5X 4X 3X 2X 1X
EPIM-2
EPIM-1
EPIM-2
EPIM-1
Page 1-2
INTRODUCTION
You can stack together up to five SEH hubs using Cabletron Systems’
external HubSTACK Interconnect cables. If you want to add
management to the stack, Cabletron Systems offers the MicroMMAC
and the SEHI intelligent hubs. You can stack up to four SEHs with
one intelligent hub. Stackable configurations let you maintain only
one IEEE repeater hop while providing up to 130 Ethernet ports.
The SEH-22/24 and SEH-32/34 are functionally identical with the
exception of the network ports:
•
SEH-22
•
SEH-24
•
SEH-32
pair segments, and one EPIM port.
, 12 RJ45 network ports and one EPIM port.
, 24 RJ45 network ports and two EPIM ports.
, one 50 pin Champ connector, providing 12 twisted
SEH-34
•
pair segments, and two EPIM ports.
1.4 SEH FEATURES
Repeater Functionality
The SEH fully conforms to the IEEE 802.3 Repeater, AUI, and
10BASE-T specifications, and provides the flexibility to connect
networks using IEEE 802.3, Ethernet Version 1 or Version 2
equipment. The SEH transmits re-timed data packets, regenerates the
preamble, extends fragments, and arbitrates collisions.
The SEH automatically partitions problem segments, and reconnects
repaired segments to the network. This feature minimizes the impact
on network operation by isolating the problem segment. Only devices
on the problem segment are affected. When the problem is solved, the
SEH automatically reconnects the isolated segment to the network.
Polarity Detection and Correction
Each twisted pair port on the SEH incorporates a Polarity Detection
and Correction feature that allows the SEH to pass data regardless of
the polarity of the twisted pair segment’s receive link. We do not
recommend operating in this condition. If you discover this condition,
remove the segment from the network and wire it correctly. This
reduces the potential for problems if equipment changes are made.
, two 50 pin Champ connectors, providing 24 twisted
Page 1-3
INTRODUCTION
LANVIEW LEDs
Cabletron Systems’ LANVIEW Status Monitoring and Diagnostics
System is a troubleshooting tool that helps you diagnose power
failures, collisions, cable faults, and link problems. The LANVIEW
LEDs are conveniently located on the front panel.
1.5 STACKABLE CAPABILITIES
The SEH is a non-intelligent hub designed to be managed by either
the Cabletron Systems SEHI intelligent hub or the Cabletron Systems
MicroMMAC intelligent hub. Intelligent hubs serve as the logical “top”
of the stack. They manage all SEH hubs in the stack providing full
packet and error statistics for the entire stack, individual device, or
individual port. You can stack together up to five SEHs for a
non-managed stack or one intelligent hub and up to four SEHs for a
managed stack. You can also add or remove hubs from the stack
without having to power down.
1.6 OPTIONAL FEATURES
The following features are not included with the SEH but can be
purchased separately from Cabletron Systems.
Ethernet Port Interface Modules (EPIMs)
EPIMs let you expand your network through a variety of media.
Cabletron offers the EPIMs shown in Table 1-1.
Table 1-1. EPIMs
EPIM Media Type Connector
EPIM-A AUI DB15 (Female)
EPIM-C 10BASE-2 Thin Coaxial BNC
EPIM-T 10BASE-T Unshielded
Twisted Pair
EPIM-X Standard Transceiver DB15 (Male)
EPIM-F1 Multimode Fiber SMA
EPIM-F2 Multimode Fiber ST
EPIM-F3 Single Mode Fiber ST
Page 1-4
RJ45
INTRODUCTION
Daughter Board Upgrade Kit
You can upgrade the SEH-22 and the SEH-32 to 24 ports using the
daughter board upgrade kit. The Cabletron part numbers for the
upgrades are:
• SEH-22: 24PORT-UGKT-E
• SEH-32: 24PORT-UGKT-E 50P
HubSTACK Interconnect Cables
You need Cabletron’s HubSTACK Interconnect cables to stack hubs
together. Table 1-2 lists the part number and application for each
cable.
Table 1-2. HubSTACK Interconnect Cables
Part
Number
9380110 12" HubSTACK
9380111 18" HubSTACK
Rack Mount or Wall Mount Hardware
You can install your SEH in a 19-inch rack or mount it on a wall.
Cabletron offers an accessory package that includes brackets and
mounting screws. The part number for the accessory package is
SEH-ACCY-KIT.
1.7 RELATED MANUALS
Us the
MicroMMAC-22E/24E and MicroMMAC-32E/34E User’s Guide
supplement the procedures and other technical data provided in this
manual. The procedures contained in these manuals are referenced
where appropriate, rather than repeated in this manual.
SEHI-22/24 and SEHI-32/34 User’s Guide
Description Application
SEH to SEH connections.
Interconnect Cable
SEHI or MicroMMAC to
Interconnect Cable
SEH connections.
and the
to
Page 1-5
INSTALLATION REQUIREMENTS/SPECIFICATIONS
CHAPTER 2
INSTALLATION
REQUIREMENTS/SPECIFICATIONS
This chapter describes network guidelines, power requirements, and
operating specifications for the SEH. Be sure to read this chapter
before you install the SEH. Your network must meet the requirements
and conditions specified in this chapter to obtain satisfactory
performance from this equipment. Failure to follow these guidelines
could result in poor network performance.
2.1 CABLE SPECIFICATIONS
The SEH network ports support both Shielded Twisted Pair (STP) or
Unshielded Twisted Pair (UTP) cabling. The Ethernet Port Interface
Modules (EPIMs) let you expand your network using UTP, STP,
Multimode Fiber Optic, Single Mode Fiber Optic, or Thin Coaxial
cabling. The rear panel Interconnect Bus Ports support Cabletron
Systems’ HubSTACK Interconnect cables for stackable applications.
Take care in planning and preparing the cabling and connections for
your network. The quality of the connections and the length of cables
are critical factors in determining the reliability of your network. The
following sections describe specifications for each media type.
2.1.1 HubSTACK Interconnect Cable Requirements
You connect units in the stack with HubSTACK Interconnect cables.
Refer to Chapter 1 for cable part numbers. The cables attach to the
SEH’s rear panel bus ports.
The rear panel of the SEH has an SEH Interconnect Bus Out Port
(male connector) and an SEH Interconnect Bus In Port (female
connector). The bus supports five stackable devices.
Page 2-1
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.1.2 UTP and STP Cable Specifications for the Network Ports
and EPIM-T Module
The device at the other end of the twisted pair segment must meet
IEEE 802.3 10BASE-T specifications. When you connect a 10BASE-T
Twisted Pair Segment to the SEH’s 10BASE-T Twisted Pair Network
Ports and EPIM-T module, your network must meet the following
requirements:
Length
The IEEE 802.3 10BASE-T standard requires that 10BASE-T devices
transmit over a
twisted pair wire. However, cable quality largely determines
maximum link length. If you use high quality, low attenuation cable,
you can achieve link lengths of up to 200 meters. Cable delay limits
maximum link length to 200 meters, regardless of the cable type.
Insertion Loss
The maximum insertion loss allowed for a 10BASE-T link is 11.5 dB
at all frequencies between 5.0 and 10 MHz. This includes the
attenuation of the cables, connectors, patch panels, and reflection
losses due to impedance mismatches in the link segment.
100
meter (328 foot) link using 22-24 A WG unshielded
Impedance
Cabletron Systems 10BASE-T Twisted Pair products will work on
twisted pair cable with 75 to 165 ohms impedance. Unshielded twisted
pair cables typically have an impedance of between 85 to 110 ohms.
Shielded twisted pair cables, such as IBM Type 1 cable, can also be
used. You should remember that the impedance of IBM Type 1 cable is
typically 150 ohms. This increases the signal reflection caused by the
cable, but since the cable is shielded, this signal reflection has little
effect on the received signal’s quality due to the lack of crosstalk
between the shielded cable pairs.
Jitter
Intersymbol interference and reflections can cause jitter in the bit cell
timing, resulting in data errors. A 10BASE-T link must not generate
more than 5.0 nsec. of jitter. If your cable meets the impedance
requirements for a 10BASE-T link, jitter should not be a concern.
Page 2-2
INSTALLATION REQUIREMENTS/SPECIFICATIONS
Delay
The maximum propagation delay of a 10BASE-T link segment must
not exceed 1000 nsec. This 1000 nsec. maximum delay limits the
maximum link segment length to no greater than 200 meters.
Crosstalk
Crosstalk is caused by signal coupling between the different cable
pairs contained within a multi-pair cable bundle. 10BASE-T
transceivers are designed so that the user does not need to be
concerned about cable crosstalk, provided the cable meets all other
requirements.
Noise
Noise can be caused by either crosstalk or externally induced
impulses. Impulse noise ma y cause data errors if the impulses occur at
very specific times during data transmission. Generally, the user need
not be concerned about noise. If noise-related data errors are
suspected, it may be necessary to either reroute the cable or eliminate
the source of the impulse noise.
Temperature
Multi-pair PVC 24 AWG telephone cables typically have an
attenuation of approximately 8 to 10 dB/100m at 20°C (78°F). The
attenuation of PVC insulated cable varies significantly with
temperature. At temperatures greater than 40°C (104°F), we strongly
recommend that you use plenum-rated cables to ensure that cable
attenuation remains within specification.
Page 2-3
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.1.3 Multimode Fiber Optic Cable Specifications for the
EPIM-F1 and EPIM-F2 Modules
Table 2-1 shows Multimode Fiber Optic Cable specifications for the
EPIM-F1 and EPIM-F2 modules.
Table 2-1. Multimode Fiber Optic Cable Specifications
Cable Type Attenuation Maximum Cable Length
50/125 µm 13.0 dB or less The maximum allowable fiber
62.5/125 µm 16.0 dB or less
100/140 µm 19.0 dB or less
Attenuation
You must test the fiber optic cable with a fiber optic attenuation test
set adjusted for an 850 nm wavelength. This test verifies that the
signal loss in a cable is within an acceptable level. Table 2-1 shows the
attenuation for each Multimode cable type.
optic cable length is 2 km
(2187.2 yards). However,
IEEE 802.3 specifications
allow for a maximum of 1 km
(1093.6 yards).
Fiber Optic Budget and Propagation Delay
When determining the maximum fiber optic cable length, the fiber
optic budget delay and total network propagation should be calculated
and taken into consideration before fiber optic cable runs are
incorporated in any network design.
Fiber optic budget is the combination of the optical loss due to the
fiber optic cable, in-line splices, and fiber optic connectors.
Propagation delay is the amount of time it takes data to travel from
the sending device to the receiving device. Total propagation delay
allowed for the entire network is 25.6 µsec, if the total propagation
delay between any two nodes on the network exceeds 25.6 µsec, then
bridges should be used.
Page 2-4
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.1.4 Single Mode Fiber Optic Cable Specifications for
the EPIM-F3 Module
Table 2-2 shows Single Mode Fiber Optic Cable specifications for the
EPIM-F3.
Table 2-2. Single Mode Fiber Optic Cable Specifications
Cable Type Attenuation Maximum Cable Length
8/125-12/125 µm 10.0 dB or less The maximum allowable fiber
optic cable length is
5 km (3.1 miles) with bridges
at each segment end. However, IEEE 802.3 FOIRL specifications specify a maximum of
1 km (1093.6 yards).
Attenuation
You must test the fiber optic cable with a fiber optic attenuation test
set adjusted for an 1300 nm wavelength. This test verifies that the
signal loss in a cable is 10.0 dB or less for any given single mode fiber
optic link.
Fiber Optic Budget and Propagation Delay
Fiber optic budget is the combination of the optical loss due to the
fiber optic cable, in-line splices, and fiber optic connectors. When
determining the maximum fiber optic cable length, the fiber optic
budget (total loss of 10.0 dB or less between stations) and total
network propagation delay should be calculated and considered before
fiber optic cable runs are incorporated in any network design.
Propagation delay is the amount of time it takes data to travel from
the sending device to the receiving device. Total propagation delay
allowed for the entire network is 25.6 µsec, if the total propagation
delay between any two nodes on the network exceeds 25.6 µsec, then
bridges should be used.
Page 2-5
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.1.5 Thin-net Network Requirements for the EPIM-C Module
When you connect a thin-net segment to the SEH (via an EPIM-C),
your network must meet the following requirements:
Cable Type
50 ohm RG-58A/U type coaxial cable must be used when making up a
thin-net cable segment.
Length
The thin-net segment must be no longer than 185 meters.
Terminators
A 50 ohm terminator must be connected to the far end of each
thin-net segment.
Connectors
A maximum of 29 tee-connectors may be used throughout the length
of cable segment for host connections. If an excessive number of barrel
connectors are used within the cable segment, such as finished wall
plates with BNC feed-throughs, then a reduced number of host
connections may be required. For special network design, contact
Cabletron Systems Technical Support.
Grounding
For safety, ground only one end of a thin-net segment. Do NOT
connect EPIM BNC ports to earth ground.
Warning: Connecting a thin-net segment to earth ground at more than
one point could produce dangerous ground currents.
Page 2-6
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.1.6 AUI Cable Requirements for the EPIM-A and EPIM-X
Modules
When you connect an external network segment to the SEH (via an
EPIM-A or EPIM-X), the AUI cable must meet the following
requirements:
AUI Cable
The AUI cable connecting the module to a device must be IEEE 802.3
type cable.
Length
The AUI Cable must not exceed 50 meters in length. If 28 AWG thin
office drop AUI cable is used, then the maximum cable length is
limited to 50 feet (15.24 meters).
Grounding
The connector shell of the EPIM-A and the EPIM-X are connected to
ground.
2.2 NETWORK PORT SPECIFICATIONS
The SEH-22 and SEH-24 network ports are shielded RJ45 connectors
that support both STP and UTP cabling. The SEH-32 and SEH-34
provide a 50 pin Champ style connector for network connections. The
following sections provide specifications for each SEH model.
Page 2-7
INSTALLATION REQUIREMENTS/SPECIFICATIONS
2.2.1 SEH-22 and SEH-24 Network Port Specifications
The SEH-22 and SEH-24 provide RJ45 connections for network
connections. Figure 2-1 shows the RJ45 pinouts.
1 2 3 4 5 6 7 8
12X
11X
10X
1. Receive + 5. Not Used
2. Receive - 6. Transmit -
3. Transmit + 7. Not Used
4. Not Used 8. Not Used
Figure 2-1. RJ45 Network Ports
2.2.2 SEH-32 and SEH-34 Network Port Specifications
The SEH-32 and SEH-34 provide 50 pin Champ connectors for
network connections as shown in Figure 2-2. Table 2-3 shows the
pinouts for the Champ connector.
24X 13X
Page 2-8
12X
Figure 2-2. SEH-34 Network Ports
1X
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