Simrad AP70 MK2, Руководство оператора

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monitor compass heading takes place. When acknowledging the alarm, the autopilot goes to
Standby mode.
When monitor compass is not available
Rudder is kept at fixed angle (i.e. heading is approximately maintained if failing when
heading keeping, turn is approximately maintained if failing when turning), alarm is given
and autopilot goes to Standby mode.
Magnetic variation missing
If heading source is set to be adjusted for magnetic variation, variation is taken from available
sensors in following order:
• position source
• navigation source
• compass
• any other variation available on CAN bus.
If variation disappears, last valid variation will be used until automatic steering is cancelled
and heading shown will then be corrected according to alternative variation in the order
given above.
Jump in heading data, check heading
If there is an abnormal heading jump in steering compass heading, an alarm will be given
and a smooth transition to new heading will take place. There may also be a compass
difference alarm if a monitor compass is in use.
Boat speed missing
If speed in use is lost, there will be an alarm and smooth transition (2 min. filter) to fallback
speed. Speed for steering and speed for navigation will use following priority and fallback:
Steering
• STW
• STW backup
• SOG
• SOG backup
• Manual speed
• Cruising speed
Navigation
• SOG
• SOG backup
• STW
• STW backup
• Manual speed
• Cruising speed
Position data missing
During NoDrift steering, alarm is given and a smooth transition to position backup source
takes place. If there is no position backup steering source, steering mode will change to auto
heading.
Navigation data missing
If lost during Nav. steering, an alarm will sound and steering will change to auto heading
steering.
Local supply voltage missing
When control unit(s) and CAN bus have different power source, alarm will be given on active
control unit with sound and flashing red power button led (display will go “black”). Main
steering computer will go to Standby mode and activate alarm on all other control units.
The alert system | AP70 MK2 Operator Manual
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