Radyne RCS20 User manual

RCS20
M:N Redundancy Switch
Installation and Operation Manual
TM056
Rev. 2.3
-NOTICE -
2003, Radyne ComStream, Inc. This manual
may not in whole or in part be copied,
reproduced, translated or reduced to any
electronic or magnetic storage medium without
the written consent of a duly authorized officer of
Radyne ComStream, Inc.
Radyne ComStream, Inc. •3138 E. Elwood St. •Phoenix, AZ 85034 •[phone] •Fax: [phone]

RCS20 M:N Redundancy Switch Warranty Policy
TM056 –Rev. 2.3 iii
Warranty Policy
Radyne ComStream, Inc. (Seller) warrants the items manufactured and sold by Radyne ComStream, Inc.
to be free of defects in material and workmanship for a period of two (2) years from date of shipment
Radyne ComStream, Inc.’s obligation under its warranty is limited in accordance with the periods of time
and all other conditions stated in all provisions of this warranty.
This warranty applies only to defects in material and workmanship in products manufactured byRadyne
ComStream, Inc. Radyne ComStream, Inc. makes no warranty whatsoever concerning products or
accessories not of its manufacture. Repair, or at the option of Radyne ComStream, Inc., replacement of
the Radyne ComStream, Inc. products or defective parts therein shall be the sole and exclusive remedy
for all valid warranty claims.
Warranty Period
The applicable warranty period shall commence on the date of shipment from Radyne ComStream, Inc.’s
facility to the original purchaser and extend for the stated period following the date of shipment. Upon
beginning of the applicable Radyne ComStream, Inc. warranty period, all customers’ remedies shall be
governed by the terms stated or referenced in this warranty. In-warranty repaired or replacement products
or parts are warranted only for the remaining portion of the original warranty period applicable to the
repaired or replaced products or parts. Repair or replacement of products or parts under warranty does
not extend theoriginal warranty period.
Warranty Coverage Limitations
The following are expressly not coveredunder warranty:
1. Any loss, damage and/or malfunction relating in any way to shipping, storage, accident, abuse,
alteration, misuse, neglect, failure to useproducts under normal operating conditions, failure to
use products according to any operating instructions provided by Radyne ComStream, Inc., lack
of routine care and maintenance as indicated in any operating maintenance instructions, or
failure to use or take any proper precautions under the circumstances.
2. Products, items, parts, accessories, subassemblies, or components which are expendable in
normal use or are of limited life, such as but not limited to, bulbs, fuses, lamps, glassware, etc.
Radyne ComStream, Inc. reserves the right to revise the foregoing list of what is covered under
this warranty.
Warranty Replacement and Adjustment
Radyne ComStream, Inc. will not make warranty adjustments for failures of products or parts, which occur
after the specified maximum adjustment period. Unless otherwise agreed, failure shall be deemed to
have occurred no more than seven (7) working days before the first date on which Radyne ComStream,
Inc. receives a notice of failure. Under no circumstances shall any warranty exceed the period stated
above unless expressly agreed to in writing by Radyne ComStream, Inc.
Liability Limitations
This warranty is expressly in lieu of and excludes all other express and implied warranties, Including
but not limited to warranties of merchantability and of fitness for particular purpose, use, or
applications, and all other obligations or liabilities on the part of Radyne ComStream, Inc., unless
such other warranties, obligations, or liabilities are expressly agreed to in writing by Radyne
ComStream, Inc.

Warranty Policy RCS20 M:N Redundancy Switch
iv TM056 –Rev. 2.3
All obligations of Radyne ComStream, Inc. under this warranty shall cease in the event its products
or parts thereof have been subjected to accident, abuse, alteration, misuse or neglect, or which
have not been operated and maintained in accordance with proper operating instructions.
In no event shall Radyne ComStream, Inc. be liable for Incidental, consequential, special or
resulting loss or damage of any kind howsoever caused. Radyne ComStream, Inc.’s liability for
damages shall not exceed the payment, if any, received by Radyne ComStream, Inc. for the unit or
product or service furnished or to be furnished, as the case may be, which is the subject of claim or
dispute.
Statements made by any person, including representatives of Radyne ComStream, Inc., which are
inconsistent or in conflict with the terms of this warranty, shall not be binding upon Radyne
ComStream, Inc. unless reduced to writing and approved by an officer of Radyne ComStream, Inc.
Warranty Repair Return Procedure
Before a warranty repair can be accomplished, a Repair Authorization must be received. It is at this time
that Radyne ComStream, Inc. will authorize the product or part to be returned to the Radyne ComStream,
Inc. facility or if field repair will be accomplished. The Repair Authorization may be requested in writing or
by calling:
Radyne ComStream, Inc.
3138 E. Elwood St.
Phoenix, Arizona 85034 (USA)
ATTN: Customer Support
Phone: [phone]
Fax: [phone]
Any product returned to Radyne ComStream, Inc. for examination must be sent prepaid via the means of
transportation indicated as acceptable to Radyne ComStream, Inc. Return Authorization Number must be
clearly marked on the shipping label. Returned products or parts should be carefully packaged in the
original container, if possible, and unless otherwise indicated, shipped to the above address.
Non-Warranty Repair
When a product is returned for any reason, Customer and its shipping agency shall be responsible for all
damage resulting from improper packing and handling, and for loss in transit, not withstanding any defect
or nonconformity in the product. By returninga product, the owner grants Radyne ComStream, Inc.
permission to open and disassemble the product as required for evaluation. In all cases, Radyne
ComStream, Inc. has sole responsibility for determining the cause and nature of failure, and Radyne
ComStream, Inc.’s determination with regard thereto shall be final.

RCS20 M:N Redundancy Switch Preface
TM056 –Rev. 2.3 v
Preface
This manual provides installation and operation information for the Radyne ComStream, Inc. RCS20
M:N Redundancy Switch. This is a technical document intended for use by engineers, technicians,
and operators responsible for the operation and maintenance of the RCS20.
Conventions
Whenever the information within this manual instructs the operator to press a pushbutton switch or
keypad key on the RCS20 Switch Front Panel, the pushbutton or key label will be shown enclosed
in "less than" (<) and "greater than" (>) brackets. For example, the Reset Alarms Pushbutton will
be shown as <RESET ALARMS>, while a command that calls for the entry of a ‘7’ followed by
‘ENTER’ Key will be represented as <7,ENTER>.
Cautions and Warnings
A caution icon indicates a hazardous situation that if not avoided, may result in minor or moderate
injury. Caution may also be used to indicate other unsafe practices or risks of property damage.
A warning icon indicates a potentially hazardous situation that if not avoided, could result in death
or serious injury.
Trademarks
Product names mentioned in this manual may be trademarks or registered trademarks of their
respective companies and are hereby acknowledged.
Copyright
2003, Radyne ComStream, Inc. This manual is proprietary to Radyne ComStream, Inc. and is
intended for the exclusive use of Radyne ComStream, Inc.’s customers. No part of this document
may in whole or in part, be copied, reproduced, distributed, translated or reduced to any electronic
or magnetic storage medium without the express written consent of a duly authorized officer of
Radyne ComStream, Inc.

Preface RCS20 M:N Redundancy Switch
vi TM056 -Rev. 2.3
Disclaimer
This manual has been thoroughly reviewed for accuracy. All statements, technical information, and
recommendations contained herein and in any guides or related documents are believed reliable,
but the accuracy and completeness thereof are not guaranteed or warranted, and they are not
intended to be, nor should they be understood to be, representations or warranties concerning the
products described. Radyne ComStream, Inc. assumes no responsibility for use of any circuitry
other than the circuitry employed in Radyne ComStream, Inc. systems and equipment.
Furthermore, since Radyne ComStream, Inc. is constantly improving its products, reserves the right
to make changes in the specifications of products, or in this manual at any time without notice and
without obligation to notify any person of such changes.
Record of Revisions
Revision
Level Date Reason for Change
16-30-96 Initial Release
1.1 9-12-96 Added cabling and interconnection drawing, added breakout panels
drawing, Added menu trees and configurable parameters.
1.2 12-06-96 Added DIP switch settings, added new J no’s to Fig. 2-1, minor
clarifications
2.0 1-10-97 Added Remote Communications specification, operator front panel
screens, enhanced operations section, added illustrations.
2.1 4-26-97 Major Revisions throughout
2.2 8-8-02 Revised and reformatted Technical Manual.
2.3 8-25-03 Revised Remote RLLP (Appendix A) Opcode 2202h.
Comments or Suggestions Concerning this Manual
Comments or suggestions regarding the content and design of this manual are appreciated. To
submit comments, please contact the Radyne ComStream, Inc. Customer Service Department.

RCS20 M:N Redundancy Switch Table of Contents
TM056 –Rev. 2.3 vii
Table of Contents
Section 1 –Introduction
1.0 Description_______________________________________________________ 1-1
1.1 Digital Data Switch (DDS20)_________________________________________ 1-1
1.2 Intermediate Frequency Switch (IFS20) ________________________________ 1-1
1.3 General Information ________________________________________________ 1-1
1.4 Channel Definitions ________________________________________________ 1-2
Section 2 –Installation
2.0 Installation Requirements____________________________________________ 2-1
2.1 Unpacking the System______________________________________________ 2-1
2.1.1 List of Items_____________________________________________________ 2-1
2.1.2 In Case of Shipping Damage _______________________________________ 2-1
2.1.3 Test Data Sheet _________________________________________________ 2-1
2.2 Site Considerations ________________________________________________ 2-2
2.2.1 Power Sources __________________________________________________ 2-2
2.3 Rack Mounting ____________________________________________________ 2-2
2.4 System Cable Configuration _________________________________________ 2-3
2.5 System DIP Switch and Jumper Settings _______________________________ 2-5
2.5.1 Data Switch Module DIP Switch Configuration__________________________ 2-5
2.5.2 Reference Distribution Module ______________________________________ 2-9
2.6.1 J1 -SD -Send Data _____________________________________________ 2-11
2.6.2 J2 -DDO -Drop Data Out ________________________________________ 2-12
2.6.3 J3 -IDI -Insert Data In____________________________________________ 2-12
2.6.4 J4 -RD -Receive Data___________________________________________ 2-12
2.6.5 J5 -ESC Audio _________________________________________________ 2-12
2.6.6 J6 -ES/ES_____________________________________________________ 2-13
2.6.7 J7 –ESC Alarm Interface_________________________________________ 2-13
2.6.8 J8 -ESC 8K Data Interface________________________________________ 2-14
2.6.9 J9-G.703 (Balanced) ____________________________________________ 2-15
2.6.10 J10 -Sync Data________________________________________________ 2-15
2.6.11 Digital Data Switch (DDS20) J1 through J10 -Switch Connector_________ 2-16
2.6.12 RCU20 Connector Pinouts _______________________________________ 2-19

Table of Contents RCS20 M:N Redundancy Switch
viii TM056 -Rev. 2.3
Section 3 –Operation
3.0 Principles of Operation______________________________________________ 3-1
3.1 RCS20 Major Assemblies ___________________________________________ 3-1
3.1.1 Central Processing Unit (CPU) Board ________________________________ 3-1
3.2 Redundant Power Supplies __________________________________________ 3-1
3.3 RCU20 Rear Panel ________________________________________________ 3-1
3.4 IFS20 Major Assemblies ____________________________________________ 3-2
3.5 IF Switch Relays __________________________________________________ 3-2
3.6 DDS20 Major Assemblies ___________________________________________ 3-2
Section 4 –User Interfaces
4.0 Operating Procedures ______________________________________________ 4-1
4.1 Front Panel Control ________________________________________________ 4-1
4.1.1 Front Panel Layout and Features ____________________________________ 4-1
4.1.2 Front Panel LCD Display __________________________________________ 4-1
4.1.3 Front Panel Keypad_______________________________________________ 4-2
4.1.3.1 MODEM-MOD CONFIG__________________________________________ 4-3
4.1.3.2 MODEM-DEMOD CONFIG _______________________________________ 4-3
4.1.3.3 MODEM-INTFC CONFIG_________________________________________ 4-3
4.1.3.4 MODEM-MONITOR _____________________________________________ 4-3
4.1.3.5 MODEM-TEST_________________________________________________ 4-3
4.1.3.6 MODEM-ALARMS ______________________________________________ 4-3
4.1.3.7 SWITCH-CONFIG SWITCH ______________________________________ 4-3
4.1.3.8 SWITCH-CONFIG SYSTEM ______________________________________ 4-3
4.1.3.9 SWITCH-MONITOR/ALARMS _____________________________________ 4-4
4.1.3.10 SWITCH-TEST _______________________________________________ 4-4
4.1.4 Front Panel LCD Indicators_________________________________________ 4-4
4.1.5 Guide to Front Panel Monitor and Control______________________________ 4-4
4.2 Remote Port Control _______________________________________________ 4-5
4.3 Terminal Port Control_______________________________________________ 4-5
4.3.1 Terminal Interface________________________________________________ 4-5
4.4 Modem Checkout and Initial Power-up _________________________________ 4-5
4.5 RCS20 Front Panel Data Entry Screens________________________________ 4-6

RCS20 M:N Redundancy Switch Table of Contents
TM056 –Rev. 2.3 ix
4.5.1 Basic Front Panel Controls_________________________________________ 4-6
4.5.1.1 Changing parameters from the Front Panel __________________________ 4-7
4.5.1.2 Moving to the Next Screen in a Menu Tree ___________________________ 4-7
4.5.1.3 Moving to the Previous Screen in a Menu Tree________________________ 4-7
4.5.1.4 Summary of Basic Front Panel Controls_____________________________ 4-8
4.6 Front Panel Menu Trees and Screens__________________________________ 4-8
4.7 Host Computer Remote Communications _____________________________ 4-12
4.7.1 Protocol Structure_______________________________________________ 4-12
4.7.2 Protocol Wrapper _______________________________________________ 4-12
4.7.3 Frame Description and Bus Handshaking ____________________________ 4-14
4.7.4 Global Response Operational Codes________________________________ 4-14
4.7.5 Collision Avoidance______________________________________________ 4-15
4.7.6 Software Compatibility ___________________________________________ 4-16
4.7.7 RLLP Summary ________________________________________________ 4-17
4.7.8 RCS20 Opcode Command Set ____________________________________ 4-18
4.7.9 RCS20 Channel Definitions _______________________________________ 4-19
4.7.10 Detailed Command Descriptions __________________________________ 4-19
4.8 Ethernet Port User Interface ________________________________________ 4-19
4.9 RCS20 Management Information Base (MIB) ___________________________ 4-19
4.10 Terminal Port User Interface _______________________________________ 4-19
Section 5 –Electrical Interfaces
5.0 RCS20 Connections _______________________________________________ 5-1
5.1 DIP Switch Settings ________________________________________________ 5-7
5.2 DDS20 Connector Pinouts __________________________________________ 5-9
5.2.1 J1 -SD -Send Data ______________________________________________ 5-9
5.2.2 J2 -DDO -Drop Data Out _________________________________________ 5-9
5.2.3 J3 -IDI -Insert Data In_____________________________________________ 5-9
5.2.4 J4 -RD -Receive Data____________________________________________ 5-9
5.2.5 J5 -ESC Audio __________________________________________________ 5-9
5.2.6 J6 -ES/ES_____________________________________________________ 5-10

Table of Contents RCS20 M:N Redundancy Switch
xTM056 -Rev. 2.3
Section 6 –Maintenance
6.0 Periodic Maintenance and Troubleshooting______________________________ 6-1
6.1 Troubleshooting ___________________________________________________ 6-1
6.1.1 Checking the Cabling and Connectors________________________________ 6-1
6.1.2 Checking the Fuses ______________________________________________ 6-1
6.2 RCS20 Alarms____________________________________________________ 6-2
6.2.1 Major Alarms____________________________________________________ 6-2
6.2.2 Minor Alarms____________________________________________________ 6-3
6.2.3 Alarm Masks ____________________________________________________ 6-4
6.2.4 Latched Alarms__________________________________________________ 6-4
6.3 Equipment Return and Repair Procedure_______________________________ 6-4
Section 7 –Technical Specifications
7.0 Introduction_______________________________________________________ 7-1
7.1 General Specifications______________________________________________ 7-1
7.2 Monitor and Control ________________________________________________ 7-1
7.4 Power and Environmental ___________________________________________ 7-2
7.5 Physical _________________________________________________________ 7-2
Appendix A –Remote RLLP
A.1 Detailed Command Descriptions _____________________________________A-1
Appendix B –SNMP MIB
Glossary

RCS20 M:N Redundancy Switch Introduction
TM056 –Rev. 2.3 1-1
Section 1 –Introduction
1.0 Description
The Radyne ComStream, Inc. RCS20 M:N Redundancy Switch provides backup
switching/protection for up to nine pairs of satellite modem channels (modulators/demodulators).
The RCS20 is a companion product to the Radyne DMD15/2400 family of Satellite Modems.
The RCS20 is comprised of three separate units that make up the switching system; the
Redundancy Control Unit (RCU20), the Digital Data Switch (DDS20) and the Intermediate
Frequency Switch (IFS20).
The RCS20 can be operated automatically, in which case an automatic backup of a failed online
modem occurs after a preprogrammed delay. The switch may also be operated manually, allowing
the operator to manually switch to a backup modem. Front panel controls and indicators provide for
auto/manual configuration, as well as display of online/off line status information for all modems in
the redundancy configuration.
Figure 1. RCS20 M:N Redundancy Switch
1.1 Digital Data Switch (DDS20)
The DDS20 provides all of the data interconnections between the online and backup modems. The
DDS20 also provides buffering of terrestrial data signals to backup modulators allowing ‘hot-standby’
modes of operation. The DDS20 receives control and DC power through an interconnecting cable
from the RCU20.
1.2 Intermediate Frequency Switch (IFS20)
The IFS20 Intermediate Frequency Switch interfaces the IF signals of the modems with the Earth
Station IF system and provides backup switching. The unit provides all of the switching relays,
signal splitters and terminations that are necessary to connect any combination of up to nine
Modulators and Demodulators to nine independent uplink and nine independent downlink
transponders. The IFS20 receives control and DC power through an interconnecting cable from the
RCU20.
1.3 General Information
Every attempt has been made to include all of the information that is necessary to properly operate
the RCS20. However, although basic information is included on theory of operation and

Introduction RCS20 M:N Redundancy Switch
1-2TM056 -Rev. 2.3
troubleshooting, this is not a service or maintenance manual. Also, the user should be fully familiar
with the operation of the individual Satellite Modems, Modulators and/or Demodulators that will be
connected to the Switch. Throughout this manual any reference to the RCS20 indicates the
combination of the RCU20, IFS20 and the DDS20. Refer to Figure 1-1 for a pictorial representation
of the RCU20 front panel, Figure 1-2 for a Functional Block Diagram of the RCS20 System and
Figure 2-7 for an interconnection diagram of the complete system including the cabling
requirements.
1.4 Channel Definitions
The RCS20 organizes the modems connected to the switch according to satellite communications
channels. These channels are labeled on the DDS20 and IFS20 panels, and are defined as follows:
Channel 0 -Backup 1
Channel 1 -Modem 1
Channel 2 -Modem 2
Channel 3 -Modem 3
Channel 4 -Modem 4
Channel 5 -Modem 5
Channel 6 -Modem 6
Channel 7 -Modem 7
Channel 8 -Modem 8
Channel 9 -Modem 9/Backup 2

RCS20 M:N Redundancy Switch Installation
TM056 -Rev. 2.3 2-1
Section 2 –Installation
2.0 Installation Requirements
This chapter instructs the user in the methods for setting up and installing an RCS20 M:N
Redundancy Switch into a Satellite Modem system. The cabling configurations for up to nine
channels and nine transponders are described.
2.1 Unpacking the System
Unseal the shipping cartons taking care not to damage the cartons, the packing material or the
equipment inside. The cartons and the packing material should be saved in the event that an
RCS20 will need to be reshipped. Examine the exterior of the units for any possible shipping
damage.
2.1.1 List of Items
Carefully remove the units from the cartons. In addition to this manual, verify that the following
items are present:
•RCS20 Redundancy Control Unit
•IFS20 or IFS20A Intermediate Frequency Switch
•2 ea. AC Power Cords
•2 ea. Bank Control 15-pin HD Sub Cables
•M:N Switch System Test Data Sheet
•M:N Switch to Modem Cable(s) for Backup Modulator and Demodulator
•Test I/O Mating Connector
•Optional 1:N Switch to Modem, I/O and Coaxial Cables for Modems 1 –9
•Optional Modem bypass cable(s) for Modems 1 –9
2.1.2 In Case of Shipping Damage
If any shipping damage is discovered to any of the above listed equipment, promptly contact the
transporter and file a damage claim. The transporter is responsible for any damage caused during
shipping. Radyne, Inc. should also be contacted.
Damage as a result of transport is not covered under the Radyne, Inc. Warranty. Refer to the
Warranty section in the front of this manual for further information.
The procedure for returning faulty or damaged equipment is contained in the warranty section in the
front of this manual.
2.1.3 Test Data Sheet
Each RCS20 M:N Redundancy Switch system is shipped with a Test Data Sheet. This report
contains information on the results of the Switch quality control testing. The report also includes
information pertaining to the system settings that were made at the factory. Radyne, Inc.
recommends that the user save this report for future reference.

Installation RCS20 M:N Redundancy Switch
2-2TM056 -Rev. 2.3
2.2 Site Considerations
Adequate site planning and preparation simplifies the installation process and results in a more
reliable system. The user should ensure that the site has adequate electrical power, environmental
controls and protection against sources of electrical radiation and interference.
2.2.1 Power Sources
The power sources should be properly grounded and as free as possible from electrical interference.
If a redundant configuration is to be used, then each power cord on the RCS20 must be plugged into
its own separate power circuit. Each circuit must have its own independent circuit breaker.
Grounding is achieved automatically when the three-prong power plug is inserted into a power
receptacle. Verify by testing that there is no voltage present between the chassis of the Switch and
the power line ground.
The protective ground must not be bypassed with a three prong to
two-prong adapter or defeated in any way. Defeating the ground may
result in operator injury or damage to the system.
2.3 Rack Mounting
The RCS20 is designed so that it can be mounted in a standard 19-inch rack. The RCS20 is 5¼”, 3
Rack Units (RU) high and must be mounted on the front of a rack with the front panel facing forward
as shown in Figure 1-1.
The DDS20 is 8¾” (5 RU) high and is preferably mounted at the top of a rack unit with the Terrestrial
Interface connectors available at the top of the rack and the modem connections available at the at
the bottom of the DDU20 in the interior of the rack. The DDS20 may also be mounted at the rear of
a rack with the Terrestrial Interface connectors available at the rear of the rack and the modem
connections available in the interior of the rack.
The IFS20A is also 8¾” (5 RU) high and is designed to be mounted at the rear of a rack with the
Up/Downconverter interface connections facing to the rear of the rack with the modem IF
connections available in the interior of the rack. The IFS20A may also be mounted in the top of a
rack with the Up/Downconverter interface connections available at the top of the rack and the
modem IF connections available inside the rack.
To allow for the easy installation of cables and adequate air circulation through the units, a
minimum of six of clearance must be provided at the sides and rear of the units. In addition, the
RCS20 requires a minimum of 1¾” (1 RU) of clearance on top of the unit.
If the Switch is mounted on slide mounts, the cables must be of sufficient length to allow the units
to be pulled forward on the mounts.

RCS20 M:N Redundancy Switch Installation
TM056 -Rev. 2.3 2-3
2.4 System Cable Configuration
This section describes the cabling configurations for the various combinations of DMD15/2400
Modulators/Demodulators/Modems and Transponders. The following figures are provided to
illustrate the proper placement of the cables:
Figure 2-1. RCU20 Rear Panel
Figure 2-2. IFS20 Rear Panel

Installation RCS20 M:N Redundancy Switch
2-4TM056 -Rev. 2.3
Figure 2-3. IFS20 Chassis Base Unit Rear Available Connectors
Figure 2-4. DDS20 Digital Data Switch Front and Rear Panels

RCS20 M:N Redundancy Switch Installation
TM056 -Rev. 2.3 2-5
Figure 2-5. DDS20 Rear Panel Interface –Data Switch Module
If either AC line cord remains connected to the RCS20, dangerous AC
voltages will be present within the Switch and the cooling fan will also be
operational. The top cover of the Switch should not be removed unless
one of the power supplies is to be replaced following the Instructions in
Section 4.
Although AC power is not present on the back plane, care must be taken
when Installing or removing a plug-in module since DC voltages will be
present.
The IFS20 and DDS20 receive DC power through the RCS20 interconnection
cable. Therefore, to ensure that no DC power is being applied to the back
plane modules, both of the Switch's AC line cords or the RCS20
interconnection cable must be removed.
2.5 System DIP Switch and Jumper Settings
The RCS20 requires several DIP Switches and jumpers to be configured for proper operation. The
DIP Switches are located on the Digital Data Switches (DDS20) and the jumpers are located on the
optional Reference Distribution Module on the RCU20 (See Figure 2-8).
2.5.1 Data Switch Module DIP Switch Configuration
Two Part Numbers exist for Data Switch Modules on the DDS20; AS/3356 (Figure 2-6a) and
AS/3478 (Figure 2-6b and 2-6c for AS/3478 Rev. A2 forward only).

Installation RCS20 M:N Redundancy Switch
2-6TM056 -Rev. 2.3
The AS/3356 Modules were shipped with older models of the DDS20. Refer to Tables 2-1 through
2-5for the various DIP Switch configurations on these assemblies.
Figure 2-6a. AS/3356 Data Switch Module

RCS20 M:N Redundancy Switch Installation
TM056 -Rev. 2.3 2-7
Figure 2-6b. AS/3356 Data Switch Module

Installation RCS20 M:N Redundancy Switch
2-8TM056 -Rev. 2.3
Figure 2-6c. AS/3356 Data Switch Module (for AS/3478 Rev. A2 Forward Only)