Paradise Datacom 4 RU Chassis, Руководство по эксплуатации

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4 RU SSPA Chassis Operations Manual 201627 REV X 45
2.4.7 N+1 Fault Detection
The N+1 system carries comprehensive fault detection logic. Each SSPA chassis proc-
esses its internal fault conditions as if it was a standalone unit. All N+1 Slave units re-
port any fault state to the Master unit, which is responsible for system wide fault state
handling. Failure of any single SSPA unit leads to a minor N+1 alarm on the Master
unit. This type of fault condition will not produce a summary system alarm.
The user may view the number of faults in a system from the front panel by selecting
the [MAIN MENU] key of the Master unit
→ up [ ▲ ] arrow to get to N+1 Master Info
Page 2. Any detected SSPA unit alarms present in the system will be displayed at the
“N+1 Alarms” screen.
If the Master unit detects two or more failed units, it will report a system-wide Summary
alarm (Summary alarm LED on the Master unit will illuminate). The cause of the alarm
will not be evaluated by the Master. To find cause of the failure, the operator will need
to evaluate the local fault conditions of the failed SSPA unit.
2.5 Reflected Power Option
When this option is installed, the user may measure the amount of reflected RF power
present at the amplifier’s output flange, with a dynamic range of 12 dB starting at the
maximum RF output. For example, an amplifier with 50 dBm (100W) of maximum
forward RF would be capable of reading reflected power levels from 38 dBm (6W) to
50 dBm (100W). The amount of reflected power can be viewed on the Front Panel
Display screen; select Main Menu
→ 1.Sys Info.
2.5.1 Reflected Power Alarm
Because the reflected power circuitry is not a true VSWR measurement, but simply a
measure of absolute reflected power, it is possible to set an alarm level. The alarm
level is factory pre-set at 80% of the HPA’s rated power. For example, an amplifier with
50 dBm (100W) of output power would have an alarm level set to 49 dBm (80W). The
alarm level is not user selectable due to possible frequent false alarms that may be
generated if set at a much lower level. The reflected power is reported to the M&C and
the user can set adjustable alarms using their M&C application.