Comtech EF Data KPA-020IN, Installation And Operation Manual

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Ku-Band Solid-State Power Amplifier Revision 0
Redundant Configuration MN/KPA.IOM
5-2
5.2.1 Control Cabling for a 1:1 System
Figure 5-1. Control Cabling of a 1:1 System
The position of the waveguide/coax switch also is automatically changed to route the signal
through the backup unit, thereby minimizing the loss of traffic.
Control cable assemblies are required to set up either a 1:1 or a 1:2 system (other RF coaxial
cables and waveguides are required as shown in Figure 5-1).
Figure 5-1 shows the control cabling for a 1:1 system. The redundant loop cable connecting the
two KPAs together provides a number of functions.
•
This cable assembly is not a straight through cable.
•
The cable assembly is labeled “backup” on one end, and KPA #1 on the other end.
•
The cable assembly is wired so that when connected to two KPAs, one KPA will
automatically configure itself as the Backup Controller and the other KPA will
automatically configure itself as the ‘Primary KPA’.
The backup KPA communicates to the primary KPA via a serial interface also provided by this
redundant loop cable assembly. This interface is used by the Backup KPA to acquire
configuration information from KPA #1. In addition, this interface provides the link for virtual
addressing as described in this manual.
Summary fault relay contacts also are included in this cable assembly and are used by the backup
KPA as an input to its switching logic. The second cable assembly is a six-wire assembly
between the backup KPA and the Waveguide Switch Assembly. Figure 5-2 shows the cabling for
a 1:2 system. Note that the functionality describes for the 1:1 cable assembly is directly
applicable for the 1:2 cable assembly. The only difference is that there is now a third connector
daisy-chained onto the cable assembly.