Furuno FEA-2107 Operator's Manual page 453

28. Trackpilot
Typical intermittent alarms not described in other chapters are:
Alarm "2010 Filter: Pos source change" appears if differential GPS used in filter positioning has changed its
operation mode either from differential mode to normal mode or normal mode to differential mode. If the steering
mode is "Goto Track" alarm "2492 Route: Needs diff Pos" also appears, if DGPS has changed its mode to normal
mode.
Alarm "2013 SOG&COG unreliable" appears when the system finds out that SOG and COG from sensors are
inaccurate. Speed/Course sensors and position sensors can be source of SOG and COG.
Alarm "2457 Route: Outside chl limits" appears when own ship goes outside the planned channel.
Alarm "2455 Route: off course", appears if the system needs more than a set limit (the limit is available in
Installation parameters) to keep the track. This alarm is repeated every five minutes, if the condition continues.
Alarm "2456 Route: WP approach error" appears if own ship speed is decreased more than waypoint approach
alarm time + 100 seconds away from the wheel over point after the user has already acknowledged alarm "2451
Route: WP approach alarm" to enable the next automatic turn. After the alarm 2456, the next turn is not enabled and
the system will generate a new alarm "2451 Route: Wp approach alarm" when appropriate.
Alarm "2460 Pilot: ROT will be exceed" appears if the set radius value in the Trackpilot panel together with the
current speed of the ship request rate of turn which is over the limit set for Max. rate of turn in the route
parameters.
Alarm "2461 Route: ROT will be exceed" appears if the planned radius for next waypoint together with the current
speed of the ship request rate of turn which is over the limit set for Max. rate of turn in the Route parameters. This
alarm is activated if the own ship is within value WP approach alarm time set in Route Parameters from the wheel
over point.
Alarm "2469 Trackpilot: off course" appears if the trackpilot needs more than a set limit (the limit is available in
Installation parameters for Go To Waypoint mode. Go To Track mode uses fixed value of 30 degrees) to keep the
track. This alarm is repeated every five minutes, if the condition continues.
Alarm "2488 Steering: Stop-System fail" appears if the system has internal failure, which prevents continuation of
Goto Waypoint or Goto Track.
Alarm "2497 Route: Stop - Sensor Fail" appears if no gyro data is received or if conditions of alarm 2475, 2476,
2478, 2492 or 2501 has been valid for last ten minutes.
Typical guidance alarms not described in other chapters are:
Alarm "2475 Route: Needs filter on", which appears if the position from the Kalman filter is not available. Alarm
2475 will be repeated every four minutes for next ten minutes and if condition still exists, alarm "2497 Route: Stop
- Sensor Fail" is generated and steering mode is automatically changed to Radius Control.
Alarm "2476 Route: Needs log sensor" appears if the position from the Kalman filter cannot be compared against
an independently operating log. Alarm 2476 will be repeated every four minutes for next ten minutes and if
condition still exists, alarm "2497 Route: Stop - Sensor Fail" is generated and steering mode is automatically
changed to Radius Control.
Alarm "2478 Route: Needs good Pos" appears if the Kalman filter did not have high precision position sensor for
route steering and position discrepancy limit between primary and secondary position or between own ship and any
position is exceeded. Alarm is repeated every 2 minutes for 10 minutes after which alarm "2497 Route: Stop -
Sensor Fail" appears.
Alarm "2492 Route: Needs diff Pos" appears for any use of Goto Track with Kalman filter but without a high
precision sensor (an example is DGPS). Alarm 2492 will be repeated every four minutes for next ten minutes and if
condition still exists, alarm "2489 Route: Changed to Goto WP" is generated and steering mode is automatically
changed to Goto WP.
Alarm "2498 Use manual rudder control" appears every two minutes to advise the operator to use manual control
of rudder, when the trackpilot has lost gyro and thus cannot control rudder.
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