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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.