Kongsberg cJoy OT
Reference high variance
You should disable the position-reference system if the event of high variance is
recurring. No corrective actions are necessary if the problem is intermittent only.
Prediction test
The prediction test detects sudden jumps in the measured position, and immediately
rejects those that lie outside the limits as illustrated in Figure 18. The test will also reject
data that drift away from the Vessel Model's predictions. The limit for the Prediction test
is a function of the actual measurement accuracy (calculated variance).
Figure 18
Prediction test
POSITION N/E
TIME
Rejected measurement
Rejection limit
Model prediction
Measurement
Rejection limit
(CD3293)
If the Prediction test limits are exceeded, the following warning message is displayed:
Reference prediction error
When this message is displayed, you should verify that the position-reference system is
rejected so that you can then disable the position-reference system.
Irrespective of the accuracy of the position-reference system, the prediction error
limit is usually not set to less than 4 m. This is done to avoid rejecting accurate
position-reference system data.
Enabling the position-reference system
Before enabling the position-reference system, ensure that the vessel speed is as low as
possible.
If the system has been in
Joystick
mode for more than a few minutes without the
position-reference system enabled, first go to
Standby
mode and then back to
Joystick
mode to reset the Vessel Model.
106
385585/C
Summary of Contents for cJoy OT
Page 207: ...Message explanations A 86 385585 C...
Page 208: ...2015 Kongsberg Maritime...
