Kongsberg cJoy OT, Руководство оператора

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Operating procedures
To avoid this, the system performs the following test:
• A wind speed measurement is rejected by the system if the wind speed is above
a predefined limit (for example 15 m/s) and increases by more than a predefined
value (for example 10 m/s).
• A wind direction measurement is rejected by the system if the wind speed is above a
predefined limit (for example 10 m/s) and the wind direction changes by more than a
predefined value (for example 60 degrees).
The wind sensor will be rejected if more than a predefined number (for example 15)
of consecutive readings are rejected according to the limits described in the previous
paragraphs. If this happens, the following alarm message is displayed:
Wind 1 rejected <current speed/direction>
In order to adapt quickly to dynamic change in wind, the input data to the test is the
difference between new measurements, and low pass filtered speed data with a small
time constant (5 seconds).
The filter is reset on three different conditions:
• Continuously reset in Standby mode.
• When the sensor
Enable
changes from
Off
to
On
.
• If there is a long time (5 minutes) since a Ready signal was received from the wind
sensor.
Operating without wind sensor input
There can be situations where you want to temporarily stop using the input from the wind
sensor, such as during helicopter operations or when operating close to another large
structure where there may be sudden disturbances of the measured wind. If you disable
the wind sensor, the system continues to use the wind speed and direction values that
were measured just before the wind sensor was disabled.
Vertical reference sensor
The vertical reference sensor (VRS) should be enabled at all times to provide the system
with pitch and roll information.
If the optional Station Keeping mode is available, this information is used to adjust the
measurements received from the position-reference system for the vessel's pitch and roll
motions. If the VRS is equipped with a heave sensor, the heave information is used for
monitoring purposes only.
If VRS information is lost, the system will be unable to compensate the received position
measurements for vessel motion. The positioning capability of the system can then
be degraded.
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