Kongsberg cJoy OT, Руководство оператора

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Message explanations
A-52 385585/C
Reference high offset
Description: This message is reported if a position reference system has an offset from the
Vessel Model. The system is not rejected. The purpose of the test is to give an
early indication of systematic errors before the position reference system is
rejected by the prediction test.
The reason for the message may be a fault in the position reference system or, if
all position reference systems show the same bias, possibly a Vessel Model failure.
The method of detection is the offset from the Vessel Model being continuously
estimated.
The limit is taken as 70 % of the prediction error limit, which in turn is a function
of the actual measurement accuracy (calculated variance).
Additional
information:
•
Limit
•
Value
Possible
consequences:
Unstable positioning.
Corrective
actions:
Check the Refsys view to verify which position reference systems are
biased/drifting.
Consider disabling one or more of the position reference systems.
Reference high variance
Description: This message is reported if the standard deviation of the measurements from a
position reference exceeds the limit.
The reason for the fault may be a fault in the position reference system, a fault in
the position reference interface to the DP-system or environmental disturbances
(air/sea).
The method of detection is the comparison of the continuously calculated standard
deviation of position reference measurements against the standard deviation limit.
Additional
information:
•
Limit for acceptable standard deviation.
•
Calculated standard deviation.
Possible
consequences:
The position reference system is rejected.
Corrective
actions:
If only intermittent, none.
Reference median deviation
Description: This message is reported if the difference between the measurements from a
position reference system and the median of all position reference systems
exceeds the limit. The system is not rejected.
The reason for the fault may be a fault in the position reference system, a fault in
the position reference interface to the DP-system or environmental disturbances
(air/sea).
Note that several GPS systems may experience the same error if they use the
same satellite system and correction signals.