Miteq NSU Instruction Manual

1
100 Davids Drive
Hauppauge, New York 11788-2034
Tel: [phone]
Fax: [phone]
www.miteq.com
TECHNICAL NOTE 25T065 DECEMBER 2006
REVE
NSU REDUNDANT SWITCHOVER SYSTEM
____________________________________
SECTION 1
INTRODUCTION
1.1 GENERAL DESCRIPTION
1.1.1 PHYSICAL
Figure 1-1. Front Panel, Control Unit
Figure 1-2. Rear Panel, NSUN Control Unit
Figure 1-3. Rear Panel, NSU2 Control Unit
Figure 1-4. Rear Panel, NSU1-R Control Unit

2
Figure 1-5. Internal View, NSU2 Control Unit
1.1.2 FUNCTIONAL
The MITEQ 1:N New Switchover Unit (NSU) is designed to provide improved reliability
for advanced satellite communications systems. The NSU consists of a Control Unit,
Switch Modules and frequency converters. The Control Unit monitors the status of up to
twelve primary frequency converters and one backup frequency converter. When a fault
is detected on a primary frequency converter, the defective converter is automatically
placed into standby and the backup converter is placed on line in place of the defective
converter using the Switch Modules. The frequency converters can be prioritized so that
critical communication channels have access to the backup converter on a prioritized
basis.
Switchover from a defective primary converter to the backup converter is achieved by
connecting the converters to a switch matrix. The defective converter is replaced by
physically removing its input/output signal lines and connecting them to the backup
converter via the switch matrix. This ensures continuous operation while the fault is
corrected, or allows for routine maintenance without disrupting signal transmission.

3
Converters can be added to unfilled positions in the chain and the settings will be
“uploaded” from the new unit to the Control Unit automatically. Conversely, when a
failed unit or switch is replaced in the redundancy chain the settings are “downloaded” to
the unit position from the settings stored in the Control Unit. This simplifies the converter
replacement process. The Control Unit is equipped with redundant hot swappable
power supplies. In the event of a power supply failure the Control Unit can remain fully
operational while the power supply is replaced.
To reduce operating costs the NSU may be placed in an unoccupied facility and be
totally controlled and monitored from a remote system controller. All front panel controls
and indications are available to a host monitor and control system. The Control Unit is
equipped with an Ethernet interface and an RS485/RS422 Serial Port interface. As an
option the RS485/RS422 Serial Port interface can be replaced with an RS232 Serial Port
interface.
A strong feature set of monitor and control functions supports powerful local and remote
control. In addition, any converter in the redundancy chain with a remote interface can
be controlled directly from the NSU Control Unit. An event log is continuously updated
with time stamped records of activity for the NSU. The resident firmware can be easily
updated via the Ethernet port.
1.1.3 NSU MODEL NUMBERS
The NSU1 is a 1:1 configuration with the switch modules integrated into a 1 rack high
chassis with the control unit. The NSU2 is a 1:2 configuration with the switch modules
integrated into the 1 rack high chassis with the control unit. The NSUN is a 1 rack high
control unit that is expandable up to a 1:12 configuration with external Redundancy
Switch Modules (RSMs). The Switch Modules specified below are intended for use with
the NSUN and can be ordered individually using the part numbers given. The standard
9800 and 9900 Series converters have been designed to physically accommodate the
Switch Module.
Redundancy Switchover Systems (1RU Controller With Integrated Switches)
1:1 integrated switches 1 IF 75 ohm, 1 RF 50 ohm NSU1-B75/S50
1:1 integrated switches 1 IF 50 ohm, 1 RF 50 ohm NSU1-B50/S50
1:1 integrated switches 1 IF 75 ohm, No RF NSU1-B75
1:1 integrated switches 1 IF 50 ohm, No RF NSU1-B50
1:1 integrated switches No IF, 1 RF 50 ohm NSU1-S50
1:1 integrated switches No IF, 2 RF 50 ohm NSU1-S50/S50
1:1 integrated switches 2 IF 50 ohm, No RF NSU1-B50/B50
1:1 integrated switches 2 IF 75 ohm, No RF NSU1-B75/B75
1:2 integrated switches 2 IF 75 ohm, 2 RF 50 ohm NSU2-B75/S50
1:2 integrated switches 2 IF 50 ohm, 2 RF 50 ohm NSU2-B50/S50
1:2 integrated switches 2 IF 75 ohm, No RF NSU2-B75
1:2 integrated switches 2 IF 50 ohm, No RF NSU2-B50
1:2 integrated switches No IF, 2 RF 50 ohm NSU2-S50
1:2 integrated switches No IF, 4 RF 50 ohm NSU2-S50/S50
1:2 integrated switches 4 IF 50 ohm, No RF NSU2-B50/B50
1:2 integrated switches 4 IF 75 ohm, No RF NSU2-B75/B75

4
1:N Redundancy Switch Controller
1:N Controller for connection to external switches NSUN
1:1 Redundancy Switch Controller With Redundant Switch Plate Assembly
1:1 Controller for connection to remote outdoor switches NSU1-R
Redundant Switch Modules
1 IF 75 ohm, 1 RF 50 ohm RSM-B75/S50
1 IF 50 ohm, 1 RF 50 ohm RSM-B50/S50
1 IF 75 ohm, No RF RSM-B75
1 IF 50 ohm, No RF RSM-B50
No IF, 1 RF 50 ohm RSM-S50
No IF, 2 RF 50 ohm, RSM-S50/S50
2 IF 50 ohm, No RF RSM-B50/B50
2 IF 75 ohm, No RF RSM-B75/B75
NOTE:
IF(BNC female) Switches are 50-180MHz, RF Switches (SMA female) are DC-18.1 GHz
Option 17C: RS232 Remote Interface
Figure 1-6. Rear Panel, Switch Module (For Use With NSUN)
1.2 EQUIPMENT CHARACTERISTICS
1.2.1 PHYSICAL
NSU Control Unit
Weight.............................................................................................................. 12 pounds nominal
Chassis Dimensions.........................................................................19” x 20” x 1.75” panel height
Converter Control and Status connectors............................................................................ DE-9S
.................................................................................................................DB-25S(NSU1-R ONLY)
Remote Interface and Status connector............................................................................... DE-9S
Ethernet Interface connector............................................................................... RJ45 Receptacle
Switch Module Bus Connectors..................................................................Serial ATA Receptacle

5
RSM Switch Modules
Weight.................................................................................................................. 1 pound nominal
Chassis Dimensions.................................................................5.6” wide x 1.61” high x 1.90” deep
........................................................................excluding connectors(see outline drawing 157773)
RF connectors............................................................................................................. SMA female
IF Connectors...............................................................................................................BNC female
Switch Module Bus Connectors..................................................................Serial ATA Receptacle
1.2.2 CONNECTOR WIRING INFORMATION
Converter Control and Status Connectors* (J1 through J13)
9-pin D-subminiature
Function Pins Normal Fault
Converter Fault Inputs 1,2 Open Closed
Converter Fault Inputs 2,3 Closed Open
Converter Control Bus Data- 5 N/A
Converter Control Bus Data+ 9 N/A
• The Control Unit must sense both Normally Open and Normally Closed contacts.
This provides the means for the Control unit to automatically recognize that a
converter has been added to the chain or removed from the chain.
Table 1-1. NSUN Switch Connections
Switch Module Bus Connectors (J14 and J15 NSUN Only)
Connector type Serial ATA
Pin Designation
1 Ground
2 Data +
3 +24V ‘A’
4 +24V ‘A’ Return
5 Data-
6 +24V ‘B’
7 +24V ‘B’ Return
Table 1-2. NSU Remote Interface Connections
Control Unit Remote Interface and Status Connector (J16)
9-Pin D-Subminiature
RS485 and RS422 RS232
Pin Designation Pin Designation
1 Ground 2 RCV Data
3 Data Out - 3 Tx Data
5 Data In - 5 Ground
7 Data Out + 7 RTS
9 Data In + 8 CTS
2 Normally Open 1 Normally Open
4 Common 4 Common
6 Normally Closed 6 Normally Closed

6
Control Unit Ethernet Interface Connector (J17)
RJ45
RJ-45 Pin Wire Color 10BaseT Signal Name
1White/Orange Transmit+
2Orange Transmit-
3White/Green Receive+
4Blue Un-used
5White/Blue Un-used
6Green Receive-
7White/Brown Un-used
8 Brown Un-used
1.2.3 CONVERTER CONNECTIONS TO THE NSU
NSU Connections
J1-J13
DNB/UPB
Block
Converter
9400/9600
Converters
9700/9800
9900
Converter
1/3rd Rack
Converters
Unit Normally-Open Pin 1 J7-1 J7-1 J3-1 J7-4
Unit Status Common
Pin 2 J7-2 J7-2 J3-2 J7-2
Unit Normally-Closed
Pin 3 J7-3 J7-3 J3-3 J7-6
RS485 Data- Pin 5 N/A J6 orJ10
Pins –3 and
5
J6 Pins –3
and 5 J6 Pins –3 and 5
RS485 Data+ Pin 9 N/A J6 orJ10
Pins 7 and 9 J6 Pins 7 and 9 J6 Pins 7 and 9
Table 1-3. Converter Connections to the NSU
The table above lists the MITEQ converters, their Redundant switch connections and
RS485 remote connections (where available) and where to connect them to the NSU
Control Unit.
NOTE: For NSU1-R mating cable assembly is provided to mate Redundant Plate
assembly to the NSU controller.
The minimum requirement for any converter connected to the NSU is a Form-C set of
contacts, which are used to indicate the fault status. In addition, any converter capable
of remote control must have its RS485 port wired to the NSU. The RS485 connection
between a Primary Converter and the NSU will enable the Primary Converter settings to
be stored automatically in the NSU. In the absence of a Serial Link between the Primary
Converter and the NSU, the Primary Converter settings must be manually stored in the
NSU. When a Primary Converter fails, its settings are transferred to the Backup
converter via the RS485 connection between the NSU and the Backup Converter. In the
case where the NSU-Converter Serial Link is disabled for the Backup Converter a fault
in a Primary Converter will cause the transfer switches to switch but none of the settings
of the Backup Converter will be changed. Converters with an RS485 connection to the
NSU should have their NSU-Converter Serial Link option enabled in the NSU.
Converters without an RS485 connection to the NSU should have their associated NSU-
Converter Serial Link option disabled in the NSU. The NSU-Converter Serial Link
options operation is described later in this document.

7
Figure 1-7. NSU1-S50 RF Connections to Converter
Figure 1-8. NSU1-B50 or NSU1-B75 RF Connections to Converter
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J2
RF
OUT
J2A
RF MON
REF
ADJUST 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
BACKUP
CONVERTER
NSU1-S50
PRIMARY
CONVERTER 01
BACKUP
Rx/Tx PRIMARY 01
Rx/Tx
NOTE: FOR 9800/9900 SERIES CONVERTERS EQUIPPED WITH ETHERNET OPTION
17H CONNECT J7 INSTEAD OF J6 OF THE CONVERTER TO THE NSU.
J3
J1
SW4 J2
J4
PRIMARY 01
IF
BACKUP IF
BACKUP
CONVERTER
NSU1-B50
OR
NSU1-B75
PRIMARY
CONVERTER 01
BACKUP IF
PRIMARY 01
IF
NOTE: FOR 9800/9900 SERIES CONVERTERS EQUIPPED WITH ETHERNET OPTION
17H CONNECT J7 INSTEAD OF J6 OF THE CONVERTER TO THE NSU.
SW1
J1 J2
J4J3
PRIMARY 01
Rx/Tx
BACKUP
Rx/Tx
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J2
RF
OUT
J2A
RF MON
REF
ADJUST 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm

8
Figure 1-9. NSU1-B50/B50, NSU1-B75/B75 or NSU1-S50/S50 RF Connections
Figure 1-10. NSU2-B50 or NSU2-B75 RF Connections to Converter
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J2
RF
OUT
J2A
RF MON
REF
ADJUST 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
BACKUP
CONVERTER
NSU2-B75
OR
NSU2-B50
PRIMARY
CONVERTER 01
PRIMARY
CONVERTER 02
BACKUP IF
PRIMARY 02
IF
PRIMARY 01
IF
NOTE: FOR 9800/9900 SERIES CONVERTERS EQUIPPED WITH ETHERNET OPTION
17H CONNECT J7 INSTEAD OF J6 OF THE CONVERTER TO THE NSU.
PRIMARY 01
Rx/Tx
BACKUP
Rx/Tx
SW1
J1 J2
J4J3
J1
J3 J4
J2
SW2
PRIMARY 02
Rx/Tx
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J2
RF
OUT
J2A
RF MON
REF
ADJUST 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
BACKUP
CONVERTER
NSU1-B50/B50
OR
NSU1-B75/B75
OR
NSU1-S50/S50
PRIMARY
CONVERTER 01
BACKUP IF BACKUP
Rx/Tx PRIMARY 01
Rx/Tx
PRIMARY 01
IF
NOTE: FOR 9800/9900 SERIES CONVERTERS EQUIPPED WITH ETHERNET OPTION
17H CONNECT J7 INSTEAD OF J6 OF THE CONVERTER TO THE NSU.
SW1
J1 J2
J4J3 J3
J1
SW4 J2
J4

9
Figure 1-11. NSU2-B75 or NSU2-B50 RF Connections to Converter
Figure 1-12. NSU2-S50 RF Connections to Converter
BACKUP
CONVERTER
NSU2-S50
PRIMARY
CONVERTER 01
PRIMARY
CONVERTER 02
BACKUP
Rx/Tx PRIMARY 02
Rx/Tx PRIMARY 01
Rx/Tx
PRIMARY 02
IF
PRIMARY 01
IF
NOTE: FOR 9800/9900 SERIES CONVERTERS EQUIPPED WITH ETHERNET OPTION
17H CONNECT J7 INSTEAD OF J6 OF THE CONVERTER TO THE NSU.
SW3
J1
J3 J4 J3
J1
J2 SW4 J2
J4
BACKUP IF
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J2
RF
OUT
J2A
RF MON
REF
ADJUST 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J1A
IF MON J1 IF
J2
RF
OUT
J2A
RF MON
REF
ADJUST 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
J5
EXT REF
INPUT
REF
ADJUST
J2A
RF MON
J2
RF
OUT 5/10 MHZ
+4 +/-3dBm
BACKUP
CONVERTER
NSU2-B75
OR
NSU2-B50
PRIMARY
CONVERTER 01
PRIMARY
CONVERTER 02
BACKUP IF
PRIMARY 02
IF
PRIMARY 01
IF
NOTE: FOR 9800/9900 SERIES CONVERTERS EQUIPPED WITH ETHERNET OPTION
17H CONNECT J7 INSTEAD OF J6 OF THE CONVERTER TO THE NSU.
PRIMARY 01
Rx/Tx
BACKUP
Rx/Tx
SW1
J1 J2
J4J3
J1
J3 J4
J2
SW2
PRIMARY 02
Rx/Tx

10
Figure 1-13. NSU2-B75/S50, NSU2-B50/S50 or NSU2-S50/S50 RF Connections
1.2.4 DEFINITIONS
Redundancy Chain
The Redundancy Chain is a series of units that have their signal paths linked together
via four-port transfer switches to achieve higher overall system reliability. This is
accomplished by having a Backup Unit standing by. In the event that a Primary Unit fails
the Control Unit will automatically place the backup unit online in the primary path and
the primary unit into the standby path by controlling the Switch Modules in the
Redundancy Chain.
The Redundancy Chain includes up to twelve primary positions and one backup
position. Each primary position includes one frequency converter and one Switch
Module. The backup position includes one frequency converter and may contain a
Switch Module for switching polarization. The NSU1 and NSU2 are fixed configurations
and cannot be expanded nor can they support polarization switching.
NSU System
The NSU1 is a 1:1 configuration with the switch modules integrated into a 1 rack unit
with the control unit. A polarization switch module cannot be added to the NSU1
System.
The NSU2 is a 1:2 configuration with the switch modules integrated into the 1 rack
control unit chassis. A polarization switch module cannot be added to the NSU2
System.

11
The NSUN System is capable of being arranged in a 1:1 up to 1:12 redundancy
configuration. A 1:1 system is comprised of the Control Unit, and one Switch Module. A
1:12 system is comprised of the Control Unit and twelve Switch Modules. A polarization
switch module may be added to the NSUN System. The RSMs are intended for use with
the NSUN and can be ordered individually using the part numbers given. The standard
9800 Series converters have been designed to physically accommodate the Switch
Module.
Control Unit
The Control Unit is responsible for the monitor and control of the NSU System.
Primary Unit
A Primary Unit is a component that is in the signal path of communications traffic. The
NSUN can accommodate up to twelve Primary Units. The NSU1 includes one Primary
Unit. The NSU2 includes two Primary Units. Each Primary Unit occupies a unique
primary position in the redundancy chain.
Backup Unit
A Backup Unit is intended to serve as a substitute for a faulty Primary Unit. The Backup
Unit normally occupies the Standby Path. If a Primary Unit fails the Control Unit will
switch the Backup Unit online into the Primary Path and the faulty Primary Converter into
the Standby Path.
Online
A unit is considered Online if the Switch Module is directing signals through a Primary
Path. This is essentially referring to transfer switch position within the associated Switch
Module. The opposite transfer switch position is Standby.
Standby
A unit is considered in Standby if the Switch Module is directing signals through the
standby path. This is essentially referring to transfer switch position within the
associated Switch Module. The opposite transfer switch position is Online.
Redundancy Chain Position
Redundancy Chain Position refers to a unique location in the redundancy chain. There
is a maximum of thirteen chain positions, one backup and up to twelve primaries. A
single frequency converter and a Switch Module occupy every primary Redundancy
Chain Position. The backup Redundancy Chain Position is occupied by a single
frequency converter. The backup position may also include a Polarization Switch
Module.

12
Priority
Each of the primary frequency converters can be assigned a priority. The NSU will grant
communication channels access to the backup converter on a prioritized basis. A
priority setting of 1 is for the most crucial communication channels. A priority setting of
12 is the least significant. In the case where the primary converters are set to the same
priority the backup is available on a first-come, first serve basis. The backup converter
has no priority.
Switch Module
The signal paths of the units in the Redundancy Chain are linked together by the Switch
Modules. The Switch Module is fixed in a redundancy chain position with a frequency
converter. The Switch Module contains an IF frequency and/or an RF frequency four-
port transfer switch. The Switch Module is connected to the Control Unit via the Switch
Module Bus. The Switch Module depicted below has both an RF and an IF four-port
transfer switch. The push-wheel is set from zero to twelve to indicate redundancy chain
position of the Switch Module (Zero is reserved for the Polarization switch). The LED
will light green for online, amber for standby, and red if there is an internal fault. There
are two connectors provided for daisy-chaining the Switch Module Bus.
Figure 1-14. Front Panel, Switch Module (NSUN Only)
Active Fault
An Active Fault indicates the NSU is presently experiencing a failure that is impeding
ideal operation of the NSU. An active fault will cause the “STATUS” button on the front
panel to light red and the status contacts will indicate a fault. The Event Log will contain
information about the fault condition and the time and date that the fault occurred.
The Types of Active Faults that can be reported are:
• Power Supply ’A’ fault
• Power Supply ’B’ fault
• Converter bus fault
• Converter Contact Failure fault
• Switch fault
• Switch Bus fault

13
NSU-Converter Serial Link
The NSU-Converter Serial Link refers to a dedicated RS485 bus connection between the
NSU and the Backup and Primary converters in the redundancy chain. The NSU-
Converter Serial Link can be enabled or disabled for each chain position independently.
With the NSU-Converter Serial Link enabled for the Backup chain position, when a
Primary Converter fails, its settings are transferred from the NSU to the Backup
converter via the NSU-Converter Serial Link. Once the NSU-Serial Link is enabled for
particular chain positions, the NSU is continuously polling those units updating the
settings stored in the NSU.
Some units in the Redundancy Chain may not be equipped with remote control. An
example would be single band block converters without remote control. In the absence
of an available RS485 connection between the NSU and a particular chain position, the
NSU-Converter Serial Link should be disabled for that chain position.
If the Backup NSU-Serial Link is disabled, a fault in a Primary converter will cause the
transfer switches to switch but none of the settings of the Backup Converter will be
changed. If the Backup NSU-Serial Link is enabled and the NSU-Converter Serial Link
is disabled for a Primary Converter, a fault in that Primary converter will cause the
transfer switches to switch and the Backup converter would be updated with the
converter settings stored in the NSU by the operator.
1.2.5 REDUNDANCY OPERATION
The equipment is capable of being connected in a prioritized redundancy arrangement.
Each redundancy arrangement includes one Backup Unit, and up to twelve Primary
Units. A Switch Module is associated with each Primary Unit. The NSU is capable of
substituting the Backup Unit for any one of the twelve Primary Units on a prioritized
basis.
Redundancy operation is achieved via four-port transfer switches that are located in the
Switch Modules. A Switch Module can be set in one of two states, online or standby.
During normal operation, only one unit in the chain can be in the standby position.
Normally, this would be the Backup Unit. The Primary units would be online. The
Control Unit monitors the Primary Units as well as the Backup Unit via the converter bus.
In the event of a Primary Unit fault: the Control Unit reconfigures the Backup Unit,
switches the Backup Unit online into the primary path, and the faulty Primary Unit to
standby. The faulty unit can then be removed leaving the Switch Module in place
without interrupting signal traffic.
1.2.5.1 REDUNDANCY MODES
There are two redundancy modes available, manual and automatic.

14
Manual Redundancy Mode
The Manual Redundancy Mode is provided to allow the operator direct control of the
redundancy chain. With the Control Unit set to the Manual Redundancy Mode, the
operator has exclusive control of the transfer switch positions. This enables off-line
testing and maintenance to be performed.
Automatic Redundancy Mode
The Automatic Redundancy Mode provides the Control Unit with complete control of
switching operations. The Control Unit monitors the Primary Units, the Backup Unit and
the Switchover Modules. The Control Unit can back up only one Primary fault at a time.
In the event of more than one failure, the Control Unit will force the faulty unit with lowest
priority (highest numeric setting) back online while backing up a faulty unit of higher
priority (lowest numeric setting).
Placing the Control Unit into Automatic redundancy mode has the following
consequences:
• All Primary Units are switched online.
• The Backup Unit is switched to standby.
• The NSU Control Unit screen switches to the Redundancy Chain Status display.
• If a Primary Unit fails, it is switched into standby and the Backup Unit is switched
online in place of the failed Primary Unit (as long as there are no higher priority
units already in standby).
a) If the fault on the Primary Unit clears, the Primary Unit is never switched back
online unless another unit with higher priority (lowest numeric setting)
develops an active fault. In this case the unit with the active fault is switched
to standby, forcing the cleared unit back online.
The flowchart below illustrates the switching decisions performed by the Control Unit
when it is placed into the Automatic mode.

15
A
ny unit fault with greater
Y
fault?
Switch faulty converter with
Y
N
N
Begin
Check converter status via converter bus.
A
ny Primary Unit fault?
priority than unit in standby?
Backup Unit
highest priority to standby.
Switch Backup Unit into Standby position and
t
Backup Unit fault?
Place all Primary Units into Auto Mode.
Y
N
Y
N

16
SECTION 2
INSTALLATION
2.1 UNPACKING, STORAGE, RESHIPMENT
Carefully open the shipping container and remove the equipment. Inspect the
equipment thoroughly and report any damage.
If the equipment is to be stored, it should be wrapped in plastic and kept in a clean, dry
place.
If the equipment is to be re-shipped for any reason, wrap the unit in heavy plastic and
ship in a heavy (275-lb. test) double wall carton. At least three inches of a solid packing
material should be used on all sides of the unit. The carton should be marked to indicate
that it contains fragile electronic equipment.
2.2 MOUNTING
THIS EQUIPMENT IS NOT FOR USE IN A DOMESTIC ENVIRONMENT.
THIS EQUIPMENT IS INTENDED FOR RACK MOUNTING.
OPERATOR INJURY MAY OCCUR IF UNIT IS NOT PROPERLY MOUNTED.
THIS EQUIPMENT MUST BE SECURELY MOUNTED.
Slides are provided for mounting the Control Unit in a standard 19" equipment rack.
Physical Arrangement of Converters in a Redundancy Chain
The converter remote interface configuration must be set to RS485, Odd Parity, and
19200 Baud with the following addresses
Backup Unit: Address 64
Primary Unit 1: Address 65
Primary Unit 2: Address 66
Primary Unit 3: Address 67
Primary Unit 4: Address 68
Primary Unit 5: Address 69
Primary Unit 6: Address 70
Primary Unit 7: Address 71
Primary Unit 8: Address 72
Primary Unit 9: Address 73
Primary Unit 10: Address 74
Primary Unit 11: Address 75
Primary Unit 12: Address 76

17
Mounting of Switch Modules in a Redundancy Chain
Brackets and associated hardware are provided such that a converter can be removed
from the rack without disconnecting the Switch Module from the redundancy chain. See
Figures 3-1 and 3-2 below for the proper arrangement for the supplied hardware. Each
successive Switch Module must be no more than one rack unit (1RU, 1.75”) from the
unit that precedes it. If additional space is required between Switch Modules, consult
the factory for an accessory package of hardware and cables to accommodate your
physical arrangement.
2.3 TURN-ON PROCEDURE
After mounting, make all external connections per Tables 1-1, 1-2, 1-3 and 2-1.
Apply power to the equipment using the power On/Off switches.
System is now operational.
DESIGNATION DESCRIPTION
Ground Lug Connect the Ground Lug on the rear panel of the equipment to the
Protective Earth connection of the building.
Power Cords Attach the power cords to the rear panel AC power inlet. Connect the
other end to the power source. Refer to national wiring standards for
the correct connection to the power source.
Converter Monitor and
Control Connectors
(J1 to J13)
This connector accepts form-c contacts from Backup and Primary
Units 1 through 12 and provides a means of converter control from the
control unit. See Paragraph 1.2.3 for wiring information.
Switch Module Monitor
and Control
Connectors
(J14, J15 NSUN Only)
The Switch Module Bus Interface connectors are daisy-chained
internally for added reliability. This is the communication link to the
Switch Modules for redundancy operation. Connect J14 to the first
Switch Module and J15 to the last Switch Module.
NSU Monitor and
Control Connector
(J16)
This is an optional connection allowing the operator to monitor and
control the equipment from a remote location. This connector also
provides form-c contacts that indicate the active fault state of the
Control Unit. See Paragraph 1.2.3 for wiring information.
Ethernet Interface
Connector (J17) The Ethernet Interface connector is an optional connection. This allows the operator to monitor and control the equipment via an
Ethernet network connection. See Paragraph 1.2.2 for wiring
information.
Table 2-1. External Connections

18
2.4 SET-UP
Description
Once all the connections from the converter to the NSU are made, the NSU detects a
set of normally open or normally closed contacts connected at the connectors from J1 to
J13. After detecting the contacts, the NSU polls the converter and the associated switch
module in each chain position for a response. If both respond, the NSU Redundancy
Chain Status display will show the switch module position (ST or ON) and the NSU then
will consider the chain position active. If the NSU-Converter Serial link is disabled for a
chain position, communication with the converter is unnecessary. If a unit does not
respond to a poll a fault will be generated and the blinking characters will appear on the
Redundancy Chain Status display in that chain position. If the NSU cannot
communicate with the converter the upper numeric characters will blink, if the NSU
cannot communicate with the Switch Module the lower characters will blink. In the case
of the switch module, if communications has never been established with the switch
module in this position the lower characters will blink ”??”. Otherwise, the last known
switch position will be displayed and blink. An event will be entered into the Event Log
as well. If the system configuration does not require a serial connection between the
NSU and a converter, the NSU-Converter Serial Link should be disabled for that
position. It is important to note that disabling the NSU-Converter serial link will prevent
the NSU from becoming automatically updated with any operational changes to that unit
although fault status will still be sensed. Once all the converters and switch modules
have been connected to the NSU and been properly setup the NSU can be switched to
the AUTO redundancy mode where it will monitor the redundancy chain.
Converter failures are determined by detecting the state of the form-c redundancy switch
contacts that come from each converter. If a Primary converter faults, the NSU will
back-up the failing unit and generate Event log entries related to the failure. If a problem
occurs with a converter’s redundancy switch contacts, they open up or they become
shorted together (states other than a normally open or normally closed fault), the NSU
will treat that as a fault and back-up the affected position. If a converter stops
responding to NSU polling, the NSU will retain the last known operational parameters
and continue to protect the converter.
If a switch module for a given path stops responding to NSU polling or the switch
indicates a fault, a fault will be reported in the NSU. The NSU will continue to operate.

19
2.4.1 RECOMMENDED SET-UP STEPS
The recommended steps for setting up the NSU are highlighted below:
• Place NSU into Local Control mode.
• Place NSU in Manual mode.
• For an NSUN Set the Switch Module push wheel, located on the rear of the switch
module to the proper address for the primary position it occupies.
• Set the converters to the recommended remote settings.
• Set NSU-Converter Serial Link enable/disable option for each chain position.
• For any converter that NSU-Converter Serial Link is disabled set converter settings
in NSU.
• Connect all of the Switch Modules to the NSUN.
• Connect all of the converters to the NSU.
• On the Redundancy Chain Status screen verify that the lower line for each converter
position in the chain reports “ST”, “st”, “ON”, or “on” and is not blinking.
• Place all converters into Remote control mode.
• Press the “AUTO” indicator button it should light green to indicate Auto mode and the
Primary converters should be Online and the Backup should be in Standby.
• Press the “AUTO” indicator button again. It should no longer be lit indicating the NSU
is now in Manual mode.
• Follow the next three steps for setting the Gain Equalization for each chain position.
• Apply an input signal to the Primary converter and measure the output signal
level of the chain position.
• From the Redundancy Chain Status screen place the Primary converter into
Standby and the Backup converter Online in its place.
• Apply an input signal to the Backup converter and from the Converter Settings
Subscreen for that chain position adjust the Gain Equalization until output level is
consistent with the measurement made on the Primary Converter.
• Follow the next four steps for setting the Slope for each chain position.
• From the Redundancy Chain Status screen place the Primary converter Online.
• Apply an input signal to the Primary converter and measure the response of at
the output. If the Primary converter is so equipped adjust the slope setting on
the Primary converter to achieve the desired response at the output.
• From the Redundancy Chain Status screen place the Primary converter into
Standby and the Backup converter Online in its place.
• Apply an input signal to the Backup converter and from the Converter Settings
Subscreen for that chain position adjust the Slope setting on the NSU until
output response is consistent with the measurement made on the Primary
Converter.
• From the Converter Settings Subscreen for each chain position set the Priority
• If using a polarization switch, from the Converter Settings Subscreen for each chain
position, Backup first, set the polarization of each converter.
• From the Converter Settings Subscreen for each chain position verify that the
settings reported by the NSU are correct and match the settings of the Primary
converters.
• Check the Status screen by pressing the “STATUS” indicator to be sure there are no
Active Faults.

20
• Press the “AUTO” indicator button it should light green to indicate Auto mode and the
Primary converters should be Online and the Backup should be in Standby.
• The system is now armed and operational.