Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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4 RU SSPA Chassis Operations Manual 201627 REV X 41
When Auto Gain is enabled, the system will automatically back off from maximum
linear gain and reserve 5dB of attenuator range for gain compensation. When this
option is enabled, the Master Unit default System Information page will display:
AutoGain(dB):XX.X.
2.2.6.6.4 N+1 Info
When selected, the menu shown in
Figure 2-15
is displayed and used for N+1 system
troubleshooting.
Note: The values shown do not indicate the current system state,
but instead offer a history of any fault occurrences.
Last Fault/Ticks
— shows different information for Master and Slave units. On the
Master unit, it displays the unit address of the last detected fault in the N+1 system. If
the display shows “000”, that indicates no fault instances since the unit assumed its
Master state. On Slave units, the value displays the amount of system clock tick
remaining since the last Master unit call. The Slave unit will assume Master state when
the tick count reaches 0.
Fault Cause
— Master unit only. Displays the cause for the last detected N+1 unit
fault. Possible values include “None,” for no faults; “Timeout,” if a Slave unit fails to
respond to a Master request for three (3) consecutive queries; or “Summary,” if a unit
exhibited a Summary fault.
2.3 N+1 Operational Basics (single unit)
A single SSPA unit may be operated in N+1 mode in order to take advantage of the
Auto Gain Control features described in
Section 2.2.6.6.3
. In this case, each SSPA
module within the SSPA chassis is counted as a separate N+1 entity. For example, a
two-module 4RU chassis acts like a two-way N+1 array.
N+1 array indexing also accounts this type of functioning. Each 4RU chassis occupies
a segment of N+1 addressing equal to the number of modules; i.e., 2 modules = 2
addresses.
The remaining N+1 functions remain the same. When one of the internal modules
develops a failure, it will be forced to mute by the internal SSPA controller. The unit will
develop a summary alarm, but will remain in N+1 master mode (if it was prior to
failure). Multi-module units will delegate a new master mode only when all internal
modules develop a failure.
Figure 2-15: N+1 Info menu
LastFault/Ticks: XX
Fault Cause: XXXXXX