User manual AUTOHELM 4000

[. . . ] Distributed by Any reference to Raytheon or RTN in this manual should be interpreted as Raymarine. The names Raytheon and RTN are owned by the Raytheon Company. AUTOHELM 4 0 0 0 Autohelm 4000 is an up-to-the-minute digital autopilot which shares the same microprocessor technology built into our biggest and most sophisticated fully installed pilots. It will provide precise powerful steering for sailing yachts up to 13m (42ft) LOA. The basic system comprises the main control unit, wheel drive unit and mountinq fittinqs (Fiq. [. . . ] When changes in vessel trim occur due to variations in wind pressure or engine throttle setting the course can only be maintained by the application of permanent rudder off-set (standing helm) to restore balance. If permanent rudder off-set is not applied to restore balance the vessel will bear on to a new heading. Under these circumstances the Autohelm 4000 detects that the original course is not being restored and continues to apply additional rudder off-set in the appropriate direction until the vessel returns to the original heading. Automatic trimming capability ensures that the originally set course is held irrespective of any changes in balance that may occur during the course of a passage. The Autohelm 4000's computer also continuously monitors the pattern of applied rudder correction and can distinguish unnecessary repetitive corrections caused by pitch and roll of the vessel from those necessary to maintain the selected heading. Note + keys always turn the vessel to starboard. Push + 1 and + IO keys together once to initiate a tack to starboard. Push once to disengage the windvane for manual steering. or Push once to change over to automatic compass heading control and maintain the current heading. 44 The Auto Tack function operates by selecting a pre-set course change (1 OO") to bring the vesselbnto the 1 opposite tack. This indicates the autopilot is adjusting trim to acquire the new course. On completing the tack and having sheeted and retrimmed the sails, the vessel may be brought onto the desired apparent wind angle by fine adjustments to the course using the + I- 1 o keys. No adjustments should be made within 1 minute of completing the tack to allow the Autopilot to compensate for the helm trim on the new tack. 13 OPERATING MODE INDICATION The operating mode of the Autohelm 4000 is indicated by a flashing LED as follows:- FUNCTIONAL TEST PROCEDURE After completing the installation you should carry out the following functional test to familiarise yourself with the system before attempting sea trials. Plug the Autohelm 4000 into the power i socket and switch on the electrical supply. The unit will emit a short beep tone to indicate that it is active and the LED will i flash to indicate Stand by operating j &`apde. The unit will emit a short beep tone on each keypress to confirm valid entries. Should the wheel move to produce a turn to port the changeover switch is incorrectly set and must be adjusted as described on page 8. The LED will be lit constantly to indicate that the unit is in Auto mode. If the yacht is swinging about its mooring, you will see that small variations in heading cause the unit to apply corrective action to the rudder. : : : ; Rudder Control Adjustment Before attempting sea trials the rudder control must first be adjusted to suit the wheel reduction ratio of your particular vessel. The rudder control setting recommended for initial sea trials may be obtained from the following chart. OPERATING MODE LED FLASHING CODE STANDBY Provides power steering. AUTO Autopilot steers to maintain compass heading. WINDVANE Autopilot steers to maintain apparent wind angle. Windvane mode is also confirmed by a single beep tone emitted every 30 seconds. I The setting recommendations above will provide stable control for initial sea trials and may, if necessary, be fine tuned later (see page 19). n ON 0 OFF SECONDS' : : Hand Held Control Unit (Cat. 2076) An optional hand held control unit can be plugged into the control unit to provide full course change capability from anywhere on board. The unit duplicates the main control units four course change keys and may be used in both Standby and Auto modes. [. . . ] The tendency towards northerly heading instability is usually more obvious at higher speeds and when it occurs can be corrected by reducing the rudder control setting. Passage making under automatic pilot is a very pleasant experience which can lead to the temptation of relaxing permanent watch. ' Remember, a large ship can travel two miles in five minutes -just the time it takes to make a cup of coffee! MAINTENANCE All moving parts of the system have been lubricated for life at the factory. Should a fault develop the autopilot's plugability ensures that only t the defective unit need be returned. [. . . ]