Saab R5 SUPREME AIS, Operation & Installation Manual

Page: 116 / 156

R5
SUPREME - Navigation System
TROUBLESHOOTING
7000 118-301, A Page 116
Green = ―Safe‖ state, estimated position error is with a 95% probability smaller than the
currently used RAIM level (shown in the upper right corner beneath the time in the
CDU).
Yellow = ―Caution‖ state, position error is unknown.
Red = ―Unsafe‖ state, estimated position error is with a 95% probability larger than the
currently used RAIM level.
8.4.3 MODE LED (multi-coloured)
This LED is not used in the R5 SUPREME Navigation System.
8.5 Troubleshooting with Alarm Messages
The R5 SUPREME Navigation System constantly monitors itself for failures, abnormal
conditions and other important parameters. Some of the monitoring trigger alarms and
those alarms are excellent aids in the troubleshooting process.
An active alarm can have two states, unacknowledged or acknowledged. The state of an
alarm will affect the STATUS LED.
A new alarm (unacknowledged) will raise a pop-up window that needs to be acknowledged
by the user. Refer to section 5.6.
The active alarms can be found in the Alarm view. Refer to section 5.11.8.
All alarms, active and inactive, can be outputted on the User Ports if configured in the
―Output Config‖, refer to section 4.2.17. The alarm status can for example be used in
interfacing centralized alarm systems. The alarms can also be monitored or recorded for
troubleshooting purposes by for example a terminal application.
The status of an alarm can be identified by two letters in the alarm sentence, ―
A
‖ and ―
V
‖.
The alarm sentence is constructed as: $GPALR,hhmmss.ss,xxx,A,A,c-c , where:
hhmmss.ss = Time (UTC) of alarm condition change
xxx = Unique alarm identifier
A = Alarm condition (A = Active, V = Inactive)
A =
Alarm’s acknowledge state, A = acknowledged, V = unacknowledged
c-c
= Alarm’s description text
$GPALR,hhmmss.ss,xxx, V ,A,c-c: Position Data Lost : Alarm is Inactive
$GPALR,hhmmss.ss,xxx, V ,V,c-c: Position Data Lost : Alarm is Inactive
$GPALR,hhmmss.ss,xxx, A , A ,c-c: Position Data Lost : Alarm is Active and Acknowledged
$GPALR,hhmmss.ss,xxx, A , V ,c-c: Position Data Lost : Alarm is Active and
Unacknowledged
The alarms that can occur in the R5 SUPREME Navigation System are listed below:
8.5.1 NAV: HDOP Limit Exceeded (ID 151)
This alarm is active when the HDOP (horizontal dilution of precision) exceeds 4.0.
8.5.2 NAV: Position Data Lost (ID 152)
This alarm is active when no valid position information is available from the R4
Navigation Sensor.