Raymarine Autohelm 6000 User Manual

Contents

Raymarine Autohelm 6000 User Manual Manual pdf 34 page image

5.0 OPERATING HINTSAutohelm 6000’s central course computercontinuously optimises automatic steeringperformance eliminating the need for operatorsupervision.It is, however, very important to understand theeffect of sudden trim changes on steeringperformance. When a sudden change in trimoccurs the automatic trim compensation systemrequires approximately 20 seconds to apply thenecessary rudder off-set to restore the automaticheading. In gusting conditions, therefore, thecourse may tend to wander slightly, particularly inthe case of a sailing yacht with badly balancedsails. In the latter case, a significant improvementin course keeping can always be obtained byimproving sail balance. Bear in mind the followingimportant pojnts:-0 Do not allow the yacht to heel excessively.0 Ease the mainsheet traveller to leeward toreduce heeling and weather helm.0 If necessary reef the mainsail a little early.It is also advisable whenever possible to avoidsailing with the wind dead astern in very strongwinds and large seas. Ideally, the wind should bebrought at least 30” away from a dead run and insevere conditions it may be advisable to removethe mainsail altogether and sail under boomedheadsail only. Providing these simple precautionsare taken the autopilot will be able to maintaincompetent control in gale force conditions.It may be noticed that the autopilot tends to bea little less stable on northerly headings in thehigher latitudes of the norther hemisphere (andconversely southerly headings in the southernhemisphere). This is caused by the increasingangle of dip of the earth’s magnetic field at higherlatitudes which has the effect of amplifying rudderresponse on northerly headings. The tendencytowards northerly heading instability is usuallymore obvious in higher speed craft and when itoccurs can be corrected by reducing the ruddercontrol setting.Passage making under automatic pilot is avery pleasant experience which can lead to thetemptation of relaxing permanent watch. This mustalways be avoided no matter how clear the seamay appear to be.Remember, a large ship can travel two miles infive minutes - just the time it takes to make a cupof coffee!5.1 UNSATISFACTORY STEERINGPERFORMANCElf the Autohelm 6000 has been correctlyspecified, installed in accordance with theinstructions and adjusted correctly it willprovide outstandingly good steering precisionover a very wide range of wind and seaconditions.If the performance falls below yourexpectations and the pilot appears to beworking correctly the fault will normally befound by carrying out the simple checksoutlined below. Before reporting your difficultiesto an Autohelm specialist, please check thefollowing:-0 Have the test procedures and adjustmentsdetailed in Sections 3.3 and 4.0 beencarried out correctly? Check again0 Has the fluxgate compass been installed inan area free from large magnetic deviation?If in doubt use a hand bearing compass tocheck6 If performance has changed recently nas amagnetic influence been introduced nearthe fluxgate compass? - anchor/chain/radioequipment/loudspeaker/tools/AC. generatoretc.l Is battery voltage correct? 12~ or 24vl Are fuses intact and of correct rating?@ Are circuit breakers engaged@ Is wiring of correct diameter and are screwconnectors firmly tight@ If pilot fails to hold course - check gainsetting at course computer and control unitsIf vessel wanders under pilot control0 Verify that drive actuator size is correct forsize and type of vessele For rotary actuator - check that reductionratio is correct for steering system of vessel0 For linear actuator - check tiller arm lengthis correct@ For hydraulic actuator - check steering ramand actuator are of compatible type andbleed system to remove air