Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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42 201627 REV X 4 RU SSPA Chassis Operations Manual
Note: With multi-module RM SSPA chassis configurations, the N+1 system will require
fewer chassis to form a N+1 redundancy array.
Examples of 4-way N+1 systems:
1 four-module 6RU, 7RU or 10RU chassis;
2 two-module 4RU or 3RU chassis;
4 one-module 4RU or 3RU chassis.
2.4 N+1 Operational Basics (two or more units)
A system which utilizes two or more SSPA chassis in an N+1 configuration may be
operated directly from the front panel as if it was a single very high power SSPA. Any
SSPA chassis in the system can serve as the Master SSPA single point of control.
2.4.1 Selecting the Master Unit
The selection of the Master chassis is fully automatic and shifts from one 4RU SSPA
chassis to another based on the priority ranking assigned to the modules comprising
each SSPA unit. A lower priority index number (referred hereafter as the N+1 Address)
means a higher rank in the N+1 hierarchy. The fault-free unit with the lowest N+1 ad-
dress is selected as the N+1 Master unit. The remainder of the units become N+1
Slave units. Slave unit settings are under full control of the Master unit. Any system-
related setting change made on the Master unit automatically propagates to the Slave
units to keep all units under N+1 control in sync.
If the Master unit develops any kind of major fault condition, it delegates its Master
privileges to the unit which is next in N+1 ranking and becomes a slave unit. This type
of control architecture eliminates a single point of failure and achieves true N+1 system
redundancy.
The Master unit is designated with a lit Online indicator and VFD display showing the
overall system state. See
Figure 2-16
.
The Online indicators of the Slave units are always turned off and the VFD displays the
message shown in
Figure 2-17
.
Figure 2-17: Front Panel Display, Slave Unit (Online indicator dark)
Figure 2-16: Front Panel Display, Master Unit (Online indicator illuminated)