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.

Installation and Operating HandbookANNOGUE

Autohelm”

.-;-: AUTOHELM 5000

The Autohelm 5000 is a modern highperformance autopilot specifically developedfor sailing and motor vessels of up to 40’(13m)LOA. It is exceptionally easy to operate and itsadvanced micro-electronic control circuit givesoutstanding steering performance.

The Autohelm 5000 is distinguished by itsautomatic course locking capability whichpermits change-over from manual to automaticsteering by a single push-button control. Fromthen on the original heading is rigidlymaintained by the automatic trim system whichcontinuously monitors trim changes and offsetsthe mean wheel position to compensate. Inaddition, the rate of wheel rotation is regulatedin proportion to the rate at which the vesselmoves off course, giving the Autohelm 5000 thesmooth steering capability of an experiencedhelmsman.

The basic system comprises a Drive Unitand Control Unit inter-connected by apluggable multi-core cable. A complete rangeof optional remote control accessories areavailable which are also pluggable to theControl Unit. After fitting the system it is onlynecessary to make a single adjustment to theControl Unit in‘,order to match the system’sresponse range to the character of a particularvessel.

The Autohelm 5000 is exceptionally easy toinstall and prepare for sea trials. Soundinstallation however is vital if the system’s highstandard of performance and reliability is to beachieved. The installation notes should befollowed carefully and in cases where specialadvice may be needed you are encouraged tocontact our Technical Sales Department whereexpert assistance is always available.

I .O SYSTEM DESCRIPTION

The Autohelm 5000 is a modular systemthat can be built up from a minimum number ofstandardised units to match the individualrequirements of a wide range of sailing andpower vessels. The rudder drive system may bechosen from a range of rotary, linear andhydraulic drive units to best suit the vessel’sparticular steering system.

The most basic installation (Fig. 1) consistsof a control unit inter-connected by a pluggablecable system to a drive unit. This installationwould be suitable for a motor vessel with asingle enclosed steering position, and where norequirement exists for remote control facilities.Hand-held remote control unit type DO73 maybe plugged directly into the Control Unitauxiliary socket.

DRIVE UNIT

.20 AMP FUSE

DC SUPPLY

Fig. 1 Basic System

20 AMP FUSE

DC SUPPLY

A simple remote control installation isillustrated in Fig. 2. The auxiliary control unitrepeats the basic working controls of the maincontrol unit and is suitable for extendingautopilot control to a secondary steeringposition. Alternatively, in the case of a sailingyacht for example, the auxiliary control unitprovides a watertight cockpit control enablingthe control unit to be mounted in a protectedposition below deck.

The full remote control system (Fig. 3)provides the addition of a hand-held remotecontrol unit.

DIRECT REMOTECONTROL (D073)

CONTROL UNIT (OPTION)

DRIVE UNIT

Fig. 2 Basic Remote Control System

DRIVE UNIT

f \ CONTROL UNIT

D C

20 AMPF U S E

SUPPLY

1J HAND HELDREMOTE CONTROL

( 0 0 9 3 )REMOTE SOCKET m

/ Ef /AUXILIARY

CONTROL UNIT

Fig 3 Full Remote Contrd System

1 .l CONTROL SYSTEM

1.1 .l CONTROL UNITThe control unit is common to all installationsand is provided with six metres of multi-corecable with pre-connected plugs and sockets toconnect to the drive unit. It houses the maincontrol circuit PCB together with the automaticcourse following compass system. The controlunit case is splash proof, but not watertight, andis, therefore, intended for mounting in a dry andprotected position. Two sockets are providedon the rear case for connecting the drive unitand remote control system.

I-- -1

r - - i142mm (5 VI

.

Rotary controls for course alteration, rudderresponse and sea state are grouped on thecontrol unit facia, together with the push-buttonprimary working controls. A secondary gaincontrol is inset into the rear case to allowadjustment of the system’s rudder responserange to match the widely differing steeringcharacteristics of both planing anddisplacement vessels. The control unit issuitable for use on 12 volt systems.

1 .1.2 REMOTE CONTROLACCESSORIES1 .I .3 AUXILIARY CONTROL UN ITAutopilot control may be transferred to theauxiliary control unit by depressing the Remotepush-button on the main control unit facia. Theauxiliary control unit is watertight and designedfor flush mounting in severely exposedpositions.

It is provided with six metres of cableterminated in a waterproof plug for directconnection to the control unit. A connector issituated on the rear case for connecting hand-held remote control deck socket.

1 .1.4 REMOTE CONTROL UNITSThe remote control is a hand-held unit thatenables the autopilot to be overriden and thevessel to be power steered from anywhere onboard. The unit is fitted with a six-metre flyinglead, Type DO73 is suitable for directconnection to the Control Unit auxiliary socket.Type DO93 is fitted with a waterproof plug forconnection to a waterproof deck socket.

1.15 REMOTE SOCKETThe remote socket provides a watertightsocket for the hand-held remote control. Thesocket is supplied with 6 metres of 3 core cable

terminating in a plugfor direct connection tothe Auxiliary Control Unit.

1 .1.6 CABLE EXTENSIONThe cable extension facilitates the lengtheningof all multi-core cables in six-metre increments.The extension cable is terminated withcompatible waterproof connectors for insertioninto the cable harness in the positions shown inFig. 3.

1 .I .7 CATALOGUE NUMBERS

CONTROL SYSTEMS

Control Unit 2068

Auxiliary Control Unit DO69

Remote Control DO93

Direct Remote Control DO73

Remote Socket DO91

Cable Extension DO59

DRIVE SYSTEMS 12v only

Rotary Z069

Linear 2070

Hydraulic 2071

Auxiliary control Unit DO69

35mm

I1 38”) 56mm (2.2”)

IHand Held Remote Control Unit (D093tDirect Remote Control (0073)

Remote Socket DO91

(3.2”) 81 mm

1 OOmm (3 9U

r

i86mm (3 38”)

0

1.2 DRIVE SYSTEMS

Mechanical steering systems may be driven byeither a rotary or linear drive unit. Some steeringsystems are fitted with an autopilot drive shaft,and in such cases the choice of a rotary drivesystem is straightforward. In general, if a driveshaft exists and lost motion does not exceed2% of total rudder movement, the rotary driveunit becomes the most economic choice. In allother cases the linear drive unit will provide thesimplest installation since it may be connecteddirectly to a tiller link on the rudder stock. Totalindependence of the mechanical steeringlinkage also allows the linear drive unit to beused to power steer the vessel in the event ofsteering linkage failure, and this is an importantsafety feature. In addition, minimisation ofworking parts improves the overall efficiency ofthe rudder drive system and reduces lostmotion to an absolute minimum.

All vessels with hydraulic steering systemswill require a hydraulic drive unit.

2 Holes: 12Smm (0.5”) diameter

1.2.1 ROTARY DRIVE UNITThe output shaft is driven by a continuouslyrated servo motor via an efficient reductiongearbox. The gearbox is dry lubricated to permitoperation in any attitude. A fail safe frictionclutch within the gear train engagesautomatically when the autopilot is switched toDuty and will disengage instantly even underextreme load when the autopilot is switchedto Set.

Supply voltage 12 voltsPeak output torque 240lb.in. (27Nm)Maximum shaft speed 18 rpmPower consumption (typical 1 S-3 ampsaverage)Suitable for vessels up to 40ft. LOA (12m)

175mm (6.88”)

r - - - - i

1.2.2 LINEAR DRIVE UNITThe output ram of the linear drive unit is drivenby a declutchable re-circulating ball leadscrewwhich enables the drive unit to .be permanentlycoupled to the rudder stock via a simple crankor tiller arm. The drive is automatically engagedby means of an internal friction clutch when theautopilot is switched to Duty and willdisengage instaltly even under heavy loadwhen the autopilot is switched to Set or Off.

25mm (1 .o”) 2 0 7 m m ( 6 . 1 5 ” )

Supply voltagePeak thrustMaximum stroke speed

Maximum strokeOverall length at mid strokeTiller arm length(+35” rudder)Maximum rudder torque

Power consumption (typicalaverage)Suitable for vessels up to

12 volts550lbs (225Kg)1.2in./sec.(30mm/sec.)12in. (300mm)27.5in. (700mm)1 Oin. (260mm)

500lb.in.(570Nm)1 Z-3 amps

40ft. LOA (12m)

51 mm (2.0”)

_ ,- _JJ

1, /

! 1 700mm lZ7.5”) I

I

mm (0.7”) RADIUS

260mm(10.0”)

--+j$--r

1.2.3 HYDRAULIC DRIVE UNITThe hydraulic drive unit consists of a precisiongear pump with integral valve block driven by acontinuously rated servo motor. A specialpressure balance valve corrects the effects ofhydraulic slip and isolates the pump from thesteering circuit when the autopilot is notenergised.

,

Supply voltageRegulated peak pressureFlow control

Peak flow rate (unloaded)

Maximum ram capacityPower consumption (typicalaverage)Overall length

12 volts4501b.in2 (30 bar)integral pilotcheck andpressurebalance valvesys tern40in3/mm(650cc/min)1 5in3 (25Occ)2-3.5 amps

9.5in. (240mm)

/L/240mm (9.5”) 117mm (4.6”)

2.0 INSTALLATION

The Atitohalm 5CCC is excepticnally easy tcinstall and prepare for sea trials. Soundinstallation however is vital if the system’s highstandard of performance and reliability is to beachieved. The installation notes should befollowed carefully and in cases where specialadvice may be needed you are encouraged tocontact our Technical Sales Department whereexpert assistance is always available.

2.1 CONTROL SYSTEM

2.1.1 CONTROL UNITThe control unit is the most sensitive part of thesystem and care should be taken to select amounting position that is reasonably free fromvibration and protected from external weatherconditions. The control unit is mounted in analuminium frame which can be pivoted topermit fixing to either horizontal or verticalsurfaces. The frame is finally fixed into positionby two No. 8 (4mm) diameter countersunk headstainless steel or brass screws.

In the case of a vessel with an enclosedwheelhouse, it would normally be desirable tomount the control unit sufficiently near to thewheel so that the controls are easily accessibleto the helmsman. However, since the controlunit incorporates a magnetic compass it isnecessary to position it at least 2ft 6in (80cm)away from the nearest steering compass in.order to avoid devi&on Df both compasses.Deviation of the control unit compass is muchless critical because of its auto-followingcapability. Nevertheless excessive deviationshould be avoided as far as possible in order tomaintain uniform sensitivity on all headings. Thecontrol unit should thus be mounted as faraway as possible from iron or other magneticdevices. If any doubt exists, the chosen siteshould be checked by means of a handbearingcompass. The handbearing compass should befixed into the chosen position and the vesselswung through 360 degrees. Relativedifferences in reading between thehandbearing compass and the main steeringcompass should not vary by more than 20degrees.

In rare cases even the above extremedeviation tolerance may not be achievable, inwhich case an alternative site remote from thesteering position must be selected. In such acase it will be necessary to operate theautopilot through an auxiliary control unitsituated near the steering position. Installationin steel hulled vessels invariably presentsdifficulties and the advice of a compassadjuster should always be sought.

Sarling yachts with a single externalsteering position are a special case where it is

8

essential to operate the autopilot via a weathsr-proof auxiliary control unit. The auxiliary controlunit would normally be mounted in the cockpitadjacent to the steering position and thecontrol unit situated below in a suitablyprotected position.

The compass within the control unit iscapable of satisfactory operation at roll andpitch angles of up to -r-30 degrees. The controlunit should, therefore, be positioned as near tohorizontal as possible to maximise gimbalaction in all directions. In the case of a sailingyacht where sustained heel angles may onoccasions exceed the above limit, it will benecessary to readjust the control unit to a nearhorizontal position on each tack. To faciliatethis, the control unit’s suspension frame shouldbe mounted parallel to the direction of the heelaxis.

2.1.2 AUXILIARY CONTROL UNITThe Auxiliary Control Unit is connected directlyto the auxiliary connector on the Control Unit.The unit is waterproof and should be positionedclose to the steering wheel. It is designed fordiscreet flush mounting and a pattern isprovided to assist panel cutting before fitting.Matching black self-tapping screws areprovided to secure the auxiliary control unitfacia in position. A good quality silicone sealantshould be used to seal between the facia andthe mounting panel.

2.1.3 HAND-HELD REMOTE’CONTROLSYSTEMIt is usually desirable to arrange for operationof the hand-held control unit from anywhere ondeck. For this purpose up to two remotesockets may be strategically positioned tomake this practical without the need for longand potentially hazardous flying leads on thehand-held unit. In the case of a sailing yacht forexample, one socket position in the foredeckarea and another in the cockpit usually makesa perfect arrangement. The sockets are flushmounted and a pattern is provided to simplifypanel cutting. Matching black self-tappingscrews are also supplied. A good qualitysilicone sealant should be used to seal the jointbetween the socket facia and the mountingface. When more than one remote controlsocket is required, the three core inter-connecting cables may be paralled togetherusing a standard cable junction box beforeconnection to the Auxiliary Control Unit.

2.2 DRIVE SYSTEMThe following notes describe the installation ofboth the rotary and linear drive units.

2.2.1 ROTARY DRIVE UNITThe rotary drive unit is coupled to the vessel’ssteering mechanism by a simple chain drive.Most steering gear manufacturers supplyspecial autopilot drive attachments and manyinclude this facility as standard.

Fig. 7 shows recommended rudder hardoverto hardover times for both planing anddisplacement vessels up to 42 feet (13m) LOA.The charts shown in Fig. 8 enables the chainreduction ratio for optimum rate of rudderapplication to be selected for both planing anddisplacement vessels. To use the charts, it isfirst necessary to determine the number of turnsof the driven sprocket when the rudder is drivenfrom hardover to hardover.

Example:A 40 foot (12m) LOA displacement vesselrequiring two turns of the driven sprocket todrive the rudder from hardover to hardover willrequire a chain reduction ratio of approximately3:l (as indicated by the dotted line on thechart). The table on the left hand side of thechart gives suitable sprocket combinations. Inthis example, the required reduction ratio of 3:lwould be best achieved by a 38 tooth sprocketdriven by a 13 Mti.mcket on the drive unit.

It should be borne in mind that thereduction ratios recommended are for the‘average case’ and that vessels broadlyclassified by length and hull type can varysignificantly in steering characteristics.Selection of the correct chain reduction ratio isnot over critical however, and any slightmismatch can usually be corrected later duringsea trials by an adjustment to the gain controlon the control unit.

Standard 3W’ pitch chain is recommendedfor the chain drive. Sprockets of 13, 15, 17, 19and 25 teeth are available as standardaccessories. Bore and keyway dimensions forthe drive unit sprocket are detailed in Fig. 4. Ifsprockets other than those supplied byNautech are fitted, it is essential that bore andkeyway dimensions specified in Fig. 4 arestrictly adhered to. The recommended drivensprockets tabulated In Fig. 8 are commonstandard sizes and should be obtainable fromlocal suppliers of chain drive equipment. Allsprockets must be “keyed” and grub screwedto their shafts, and finally secured with ‘Loctite’.

The drive unit is mounted by bolting to asubstantial frame member (Fig. 5). The ‘1shaped mounting foot is secured by four

equally spaced caphead screws, and may berotated through 90 degrees to provide a moreconvenient mounting position if required (Fig. 6)tn some cases, it may be necessary tofabricate a special frame to mount the driveunit. It should be noted that chain tension canexceed 3OOlb (.l.50kg), and thus an extremelyrigid mounting structure is vital to maintaingood chain alignment. Installation failuresfrequently occur in this area, and as a generalrule it is desirable to ‘over engineer’ the driveunit mounting.

3.22-3.24mm(0.127”-0 1275”)

1

9 46 -9 61 mm LJG R U B S C R E W

(0.3725”-0.3765”l

/ /

19mm(0.75” )

127mm(0 .5” )

Fig. 4

Rrovision must also be r;;ade for chainadjustment, which is most easily achieved byremovable shims placed under the mountingfoot, or by elongated clearance holes in themounting frame as illustrated in Fig. 6. Bothsprockets must be accurately aligned to run inthe same plane, and this must be carefullychecked by means of a straight-edge.

The grease lubricated gearbox permitsmounting of the drive unit in any convenientattitude without risk of oil leakage. The driveunit’s sprocket may also face any direction,since steering sense can be corrected bymeans of a phase switch located in the controlunit.

Finally, the chain should be tensioned untilit is ‘just’ tight and contributes negligible lostmotion to the drive system. Total lost motionbetween the driven sprocket attached to thesteering system and the rudder stock shouldnot exceed 2% of total movement. If lost motionexceeds this level, it should be corrected,otherwise steering performance will beimpaired.

Fig. 8

HARDOVER-HARDOVERTIME RECOMMENDATIONS

40

1

Fig. 7

.-., FFFT

-.

2.2.2 LINEAR DRIVE UNITThe linear drive unit couples directly to therudder stock at the tiller arm lengthrecommended in Fig. 9. It is usuallypreferable to couple the linear drive unit to therudder stock via an independent tiller arm(Edson offer a standard fitting). In certain cases,however, it may be possible to couple thepushrod to the same tiller arm or rudderquadrant employed by the main steeringlinkage. It is important to note that the lineardrive system can exert a thrust of 550lbs. If anydoubt exists about the strength of the existingtiller arm or rudder quadrant the steering gearmanufacturer must be consulted.

The method of bolting the pushrod ball endto the tiller arm or rudder quadrant is illustratedin Fig. 11. It is vitally important that thecoupling bolt is fully tightened and the nutlocked by means of the locking tab provided.The standard ball end fitting will allow for amaximum angular misalignment between thepushrod and the tiller crank plane of rotation ofup to 5”. Accurate angular alignment isextremely important and under nocircumstances should the above extreme limitsbe exceeded. The body of the drive unit ismounted by bolting to a substantial framemember (Fig. 10). As a general rule it isdesirable to ‘over engineer’ the linear driveunit’s mounting structure to ensure reliabilityand maintenance of correct alignment. Anexcessively fletibk mount can also severelyimpair the steering performance of theautopilot.

It is important to ensure that the total ruddermovement is limited by the rudder stops builtinto the vessel rather than the end stops of thelinear drive output.

LINEAR DRIVETILLER ARM LENGTHS

INS CM

‘*- 3 0

1’- ‘._ .,

lI: *;L.-.yy

5-METRES

I I 1 1 I I8 9 10 11 12 13

FEETI I I I

25 3 0 3 5 40LOA

Fig. 9

1 1

2.2.3 HYDRAULIC DRIVE UNITThe hydraulic drive unitshould be mountedclear of spraj/ and the possibility of immersionin water. It should be located as near aspossible to the hydraulic steering cylinder. It isimportant to bolt the hydraulic drive unitsecurely to a substantial member to avoid anypossibility of vibration that could damage theinter-connecting pipework.

The drive amplifier (Fig. 13) should bemounted between the drive unit and the powersupply (batteries) in order to minimise the totallength of power cable. It should also bemounted in a position clear of bilge water andspray. The drive amplifier is mounted by firstremoving the cover marked ‘Autohelm’ andbolting or screwing to a suitable verticalbulkhead through the four holes in the .base(Fig. 14).

There are three basic types of hydraulicsteering system (Fig. 12). Typical connectionpoints for the drive unit are shown in each case.In all cases it is strongly recommended thatthe steering gear manufacturer beconsulted. The drive unit valve block is tappedl/4” BSP to accept suitable pipe fittings andDowty sealing washers are supplied (Fig. 15).

CONTROL UNIT POWER SUPPLY CABLECOiVfylECTlON SOCKET fve I

Two Line System

222mm (8 7”)*

8Fig. 13 Drive Amplifier

I DRIVE UNITEARTHING TERMINAL CONNECTION

Two LinePressurised System

-RESERVOIR LINE

-ve

Fig. 14 Drive Amplifier Wiring Diagram.

Three Line System

PRESSURISED

wFig. 12

RESERVOIR LINE

Minimisation of hydraulic fluid loss duringconnection of the drive unit will help to reduce.the time and effort required later to bleed thesystem of trapped air. Absolute cleanliness isessential since even the smallest particle offoreign matter could interfere with the correctfunction of precision check valves in thesteering system.

When the installation has been completedthe hydraulic pump may be operated byswitching the control unit to Duty and operatingthe Steer control. Greater motor movements willbe obtained if the gain control on the coursecomputer is set to No. 10 and the ruddercontrol set to maximum.

The hydraulic steering system should bebled according to the manufacturer’sinstructions. From time to time during thebleeding process the drive unit should be runin both directions to clear trapped air from thepump and inter-connecting pipe work.

If air is left in the system the steering willfeel spongy particularly when the wheel isrotated to the hardover position. Trapped air willseverely impair correct operation of theautopilot and the steering system and must beremoved.

During the installation of the system it hasnot been necessary to keep track of theconnection sense to the hydraulic steeringcircuit since operating sense of the autopilotcan be corrected if necessary by reversing thepolarity of* pump drive motor connections(see section 3.3.1).

To check correct phasing of the_autopilot,switch to Duty and rotate the Steer controlclockwise. If phasing is correct starboardrudder movement will result. If opposite ruddermovement occurs, reverse the phase switchdirection to correct as described in Section 3.2.

The gain control located on the back of theControl, Unit sets the rudder response of theautopilot to match the particular installation.The recommended gain control setting is givenin Fig. 16.

CONNECTION OFHYDRAULIC LINES TO PUMP

DOWTY SEAL

’ BSP FITTING

Assembly for W’ BSP Line Fitting

Fig. 15DOWTY SEAL

- I

#=%I ‘h” NPT FllTlNG

Assembly for l/d’ NPT Line Fitting

ii3 IN3 RECOMMENDED GAI50b 3 0 -1 CONTROL SETTINGS

5-

O-

1 _#” __.ii.

15/

N

I I I II ” 11 11 2 3 4 5 6 7 8 9 1 0

GAIN CONTROL AVERAGE SE-tllNG

Fig. 161 3

2.3 CABLING AND POWER SUPPLIES

2.3.1 SIGNAL CABLINGCable inter-connections between system sub-units are shown schematically in Figs. 1, 2, and3. The interconnecting multi-core cablebetween the control unit and drive unit is 20feet (6m) long, and is supplied with the controlunit. All other interconnecting cables aresupplied with their related sub-unit and are also20feet (6m) in length. All 7 core cables aresupplied with pre-wired waterproof connectorsand are extendable in 20 feet (6m) incrementsby the addition of standard cable extensions(Cat. No. 059) as shown in Fig. 3.

Cable connector clamp nuts should besecurely tightened to ensure watertight joints.All cables should be run at least 3ft (1 m) fromexisting cables carrying radio frequency orpulsed signals, and should be clamped at 1.5foot (05m) intervals.

2.3.2 DC SUPPLY CABLEAs a general rule the DC supply cable to thedrive unit should be kept as short as possible,and have a conductor area of 1 .O sq.mm permetre run to minimise voltage drop.

Example:Length of cable Conductor area Cable sizeUp to 2.5m 2.5 sq.mm 50/0.25mmUpti4m 4 scpnm 56/0.3mm

The two supply cables must run directly fromthe vessel’s battery or alternatively from themain distribution panel, and a 20 amp fuse oroverload trip should be included in the circuit.It is important not to tap into supplies to otherinto supplies to other equipment to avoid thepossibility of mutual interference.

The drive unit is supplied with 1.5ft (0.5m)power supply cable tails. These should beconnected to the main power supply cable viaa heavy-duty terminal block. The red cable tailshould be connected to the positive supply andthe black cable to the negative supply. Ifpolarity is accidentally reversed the equipmentwill not operate, but no damage will result.

The drive unit case must be bonded to themetal hull or engine frame and a heavy dutyconductor (2.5mm2) should be used for thispurpose.

14

3.0 OPERATION

3.1 BASIC PRINCIPLES

The following description of the Autohelm 5000principle of operation will help in providing acomplete understanding of its controls. Thecontrol unit houses an extremely sensitive auto-setting electronic compass. When the autopilotis in operation, deviation from course iscontinuously monitored by the compass andcorrective rudder is applied by the drive unit toreturn the vessel to course. The amount ofapplied rudder is proportional to the courseerror at any time, and thus when the originalcourse is restored the rudder will beneutralised. The amount of the rudder appliedfor a given off-course error is adjustable tomatch both the steering characteristics of thevessel and speed through the water. A vesselwith a small rudder for example, will requiremore corrective helm than a similar sized vesselwith a larger rudder. Similarly, a high speedpower boat will require considerably lesscorrective helm at planing speeds than it will atlower displacement speeds (Fig.1 8.)

The characteristic which distinguishes theAutohelm 5000 is its ability to make automaticcorrection for changes in trim or weather helm.When changes in trim occur the set course canonly be maintained by the application ofpermanent rudder offset to restore balance.Many automatic pilots are incapable of this andwill allow the vessel to bear on to a newheading to achieve a new state of balance.

Under these circumstances the Autoheim 5000detects that the original course has not beenrestored and will continue to apply additionalhelm in the appropriate direction until thevessel returns to the original heading. Thisfacility ensures that the originally set course isheld irrespective of changes in balance thatmay occur during the course of a passage.

3.2 CONTROLS

3.2.1 CONTROL UNITFig.1 .I shows the position of all controls. Eachcontrol has the following functions:

OFFPush to de-energise the autopilot. The electro-magnetic clutch in the drive unit is disengagedfor manual steering.

SETPush to energise the compass circuit andinitiate the automatic compass settingsequence. The compass is finally set to themanually steered heading when both the redand green pilot lights are extinguished.

DUTYPush to fully energise the autopilot forautomatic steering duty.

REMOTEPush to transfer basic automatic pilot control tothe auxiliary control unit.

SEARotate to adjust compass sensitivity to suit seaconditions. In position ‘0’ the compass is fullysensitised for operation in calm sea conditions.Clockwise rotation to position ‘7’ progressivelydensensitises the compass for operation inrough sea conditions. Adjustment of thisimportant control is fully discussed later.

R U D D E RRotate to adjust rudder response. In position ‘0’rudder movement is minimised. Clockwiserotation to position ‘7’ progressively increasesthe amount of applied rudder. Adjustmenttechnique is fully discussed later.

STEERRotate counter-clockwise or clockwise to altercourse to port or starboard respectively. Eachscale division represents 5 degrees of coursealteration. The steer control will rotateautomatically when the control unit is switchedto Set.

The controls on the rear case are used toadjust the auto-pilot’s response to suit theparticular installation and the vessel’s steeringcharacteristics.

Each control has the following functions:GAINPresets the overall system gain to compensatefor variations in the mechanical reductionbetween the drive unit and the rudder and thevessel’s steering characteristics. For initial seatrial purposes this control is set according tothe recommendations given in Fig.1 8.

PHASE SWITCHThe phase switch is located on the internalPCB and is accessible by removal of a blankrubber grommet from the rear case. The phaseswitch reverses the direction of correctiverudder action and its setting procedure isdescribed later.

NB Recommended gain control settings forhydraulic drive installations are given inthe hydraulic drive unit instructions.

GAIN DRIVE UNIT AUXILIARYCONTROL SOCKET CONTROL SOCKET

Fig. 17 PHASE SWITCH

3.2.2 AUXILIARY CONTROL UNITAutopilot control may be transferred to theauxiliary control unit (Fig.1 9) by depressing theRemote push-button on the main control unitfacia.

Two independent rotary switches areprovided on the auxiliary control unit. The firstpermits Mange-over betweenSet and Dutymodes. The second control permits remotealteration of heading. Switch movement to theleft or right initiates course alteration to port orstarboard respectively at approximately onedegree per second.

3.2.3 REMOTE CONTROL UNITThe hand-held remote control unit (Fig.20)enables the autopilot to be switched out andthe vessel to be power steered from anywhereon board. Its flying lead may be plugged intoany one of the remotely positioned waterproofsockets and should be switched to Auto fornormal automatic steering operation. Theautopilot may be overriden by switching toManual and the vessel then power steered bymeans of the control wheel. The automatic trimsystem continues to operate in the manualsteering mode and a straight course will besteered when the ‘boat’ on the control wheel isaligned with the remote control centre line. Theoriginal course is remembered and will beresumed immediately the change-over switch isreturned to Auto. If the vessel has been powersteered by the remote control for a long periodit is important to check that there is no chanceof collision when the original automaticheading is acquired by switching back to Auto.

16

RECOMMENDED GAINCONTROL SETTINGS

l - l

METRES/ I I I I I 1

7 8 9 10 1 1 12 13

FEETI I I I

2 5 3 0 35 40

‘,_ LOA

,,. _s., . I”

Fig. 18

Fig. 19

Fig. 26

I

.CONTROL WHEEL

4.0 FUNCTIONAL TEST PROCEDURES

The following functional test procedure isrecommended before attempting sea trials.

4.1 MAIN CONTROL UNIT

0

0

0

0

.*

Switch to Set and observe that the compassautomatically sets to the present heading.The Steer control will rotate while thecompass is setting and slow down as thenull position is approached. When thecompass is finally set both pilot lights will beextinguished.

Switch to Duty and check that the drive unitclutch is engaged by attempting to rotatethe steering wheel.

Adjust the Sea and Rudder controls to ‘0’.Then adjust the Steer control one or twodivisions clockwise and then counter-clockwise. The steering wheel should rotatein the same direction as the Steer control. Ifopposite wheel rotation occurs, reverse thephase switch. (A small screwdriver will berequired to operate the phase switch afterremoval of the blank rubber grommet fromthe rear case).

Increase Rudder control setting and notethat larger wheel movements result when theSteer control is adjusted.

Increase theSea control setting and notethat larger movements of the Steer controlare necessary in either direction b.eforesteering wheei movement commences.

The automatic trimming capability of the 0 Ensure that the chain and sprockets drivingautopilot can be observed by the following test: the actuator move freely and in alignment.

Switch to Set to realign the compass. Thenswitch to Duty and offset the Steer control byapproximately two divisions i.e. approximately10 degrees of heading change. This effectivelysimulates a condition where the need forstanding helm has developed and the vessel isnot returning to course. You will notice that afteran initial fixed helm has been applied the driveunit continues to apply further helm movements,but at a much slower rate. If left in this conditionthe wheel will eventually rotate hardover. If,however, the vessel is moving through the waterthe progressive application of additional helmwill eventually return the vessel to its originalcourse with the necessary standing helmapplied. This can be simulated by rotating thesteer control back to the original courseposition. The progressive application ofstanding helm will cease when the compasssenses that the original course has beenrestored.

0 Ensure that chain tension is adjustedcorrectly (see 2.2.1)

0 Select Duty and rotate the Rudder controlseveral turns to the right to drive the rudderhardover.

0 When the actuator drives the rudder onto themechanical limit stops ensure that themounting of the drive actuator shows nosign of movement.

0 Rotate the Rudder control in the oppositedirection to reverse the rudder drive to theopposite end stop. Check for any movement.

4.2 AUXILIARY CONTROL UNIT

0 Switch the auxiliary control unit to Set andthen depress Remote on the main controlunit. In this position the compassautomatically sets to the present heading.

0 Switch the auxiliary control unit to Duty andcheck that.the drive unit clutch is engagedby attempting to rotate the steering wheel.

4.3 MECHANICAL TESTPROCEDURES

Before attempting sea trials it is important toverify that the vital link between the Autohelm5000 drive actuator and the vessel’s steeringsystem is free of obstruction and operatingcorrectly.

It is strongly advised that the followingsimple checks are carried out.

WarningWhen the steering system is being movedmanually or under drive from the actuator donot touch any part of the system, sprockets,chains or limit stops. The forces exerted areconsiderable and could cause injury.

Rotary Drive UnitLocate the actuator and with an assistant toturn the main steering wheel switch on the pilot.

0 Press Set - turn the steering wheel fromhardover to hardover. ’

Linear Drive Unit0 Proceed as for rotary drive unit.

0 Check that at no point during movement ofthe steering quadrant and linear driveactuator from hardover to hardover does theactuator foul any part of the quadrant,steering mechanism or yachts structure. Anyfouling under load could damage the driveactuator.

0 Check that the Drive actuator operateshorizontally and that angular movement ofthe ball end fitting is minimal (So maximum).

0 Select Duty and rotate the Rudder controlseveral times to drive the rudder hardover.

0 When the rudder is driven hardover checkthat the mechanical limit stop on thevessel’s steering system is reached beforethe actuator reaches its mechanical limit.

0 When the rudder drives hard against the endstop check there is no visible movement ofthe actuator mounting pedestal or thestructure supporting it.

0 Rotate the Rudder control in the oppositedirection and repeat the checks with therudder driven hardover inthe oppositedirection.

Hydraulic System0 Proceed as for the rotary drive unit.

l Check that all unions are tight and there isno seepage of hydraulic fluid.

l Select Duty and rotate the Rudder controlseveral times to drive the rudder hardover.

l Rotate the Rudder control in the oppositedirection and drive the rudder hardover inthe opposite direction.

0 Check that the steering ram moves smoothlyand that there is no excessive play orjerkiness in the movement.

The performance of the Autohelm 5000 willonly reach the designed levels if the installationof the actuator and steering system is correctlyengineered and adjusted. It is strongly advisedthat these be checked before sea trials.

5.0 SEA TRIALS

Initial sea trials should be carried out in calmconditions and with plenty of sea room. Thepreviously conducted functional test will haveverified that the autopilot is operating correctlyand that you are familiar with all of its controls.

Check that the gain control on the rear ofthe control unit is adjusted to the settingrecommended for the particular vessel categorygiven in Fig. 3.1, Then set the Sea control to ‘0’and the Rudder control to ‘4’.

Initial sea trials on fast planing vesselsshould be conducted at no more than halfengine throttle under which conditions therecommended mid-way setting of the ruddercontrol should give acceptable steeringperformance. A mid-way setting of the ruddercontrol will also give acceptable steeringperformance in sailing and displacement powervessels under all conditions for initial trialpurposes. Fine setting of the Rudder control isdiscussed later.

5.1 FIRST TRIALS.The following initial trial procedure isrecommended:

0 Steer manually on to a fixed heading andhold the course steady.

0 Switch the autopilot to Set and allow up to1.5 seconds for the compass to adjustautomatically to the manually steered

: heading.0 Switch to Duty and the autopilot will

automatically take control. In calmconditions an extremely constant headingwill be maintained.

0 Increase the setting of the Sea control untila good heading is achieved with a minimumnumber of wheel movements. Correct settingof this control for varying sea conditions isessential to avoid unnecessary wear andtear on the autopilot and to minimiseelectrical power consumption.

0 Alter course to port or starboard using theSteer control on the main control unit, (orthe Left/Right control on the auxiliarycontrol unit with the main control unitswitched to Remote). Major coursealterations are best applied by switching toSet and then manually steering the vesselon to the new heading. When the newcourse is acquired, hold for a few secondsand then switch the autopilot back to Dutyto maintain the new heading.

0 If a hand-held remote control is fitted, switchfrom Auto to Manual and then power steerthe vessel by the control wheel. Switch backto Auto and the vessel will return promptlyto the original heading.

0 When the autopilot is set to Duty return tomanual steering may be instantly achievedby switching to Set or Off on the maincontrol unit. It is very important to rememberthat manual control can only be obtained onthe auxiliary control unit if the main controlunit is switched to Remote. The importanceof being able to regain manual control ofsteering must-be stressed. The Off button iscoloured red for easy identification andmanual take-over procedures should bepractised at an early stage.

5.2 RUDDER CONTROL ADJUSTMENT

The gain control on the rear of the control unithas been previously set according to therecommendation given in Fig. 3.1. This controlsets the range of adjustment available on themain panel Rudder control and in all butextreme cases should not need furtheradjustment.

In all cases, excessive rudder applicationresults in ‘oversteer’ which can be recognisedby the vessel swinging slowly from side to sideof the controlled heading. In addition, distinctovershoot will be observed when the course ischanged. This extreme condition may becorrected by reducing the Rudder controlsetting.

Similarly, insufficient rudder application willresult in sluggish steering response which isparticularly apparent when changing courseusing the Steer control. This condition iscorrected by increasing the Rudder controlsetting.

Oversteering and understeering tendenciesare most easily recognised in calm seaconditions where wave action does not maskbasic steering performance.

The operational adjustment technique for theRudder control varies significantly betweenplaning and displacement craft and is ,,described separately below.

5.2.1 PLANING CRAFTPlaning craft operate over a very large speedrange. Rudder effectiveness increases verysignificantly at higher hull speeds and it is thusnecessary to reduce the Rudder control settingas speed increases to avoid oversteer. Innormal cases the rudder control setting wouldbe reduced almost to ‘0’ at maximum planingspeed and increased towards ‘7’ at minimumdisplacement speeds. Oversteer can beextremely violent at planing speeds and it isthus essential to reduce the rudder settingbefore opening the throttle.

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5.2.2 DISPLACEMENT POWERVESSELSThe Rudder control setting is much less criticalon this type of vessel and it is not normallynecessary to change the setting for differentengine speeds. As a general guide initialtesting should be carried out at setting ‘4’ andreduced as much as possible ‘consistent withgood heading control to minimise wear andtear on the steering ‘system.

5.2.3 SAILING CRAFTSailing craft average hull speeds do not varygreatly and thus the Rudder control setting canremain fixed most of the time. Initial testingshould be carried out at setting ‘4’. Sailing craft,however, are particularly stable when sailingclose hauled and under these conditions it isusually possible to reduce the Rudder controlsetting to minimise rudder movement andhence power consumption. Conversely, whensailing down wind, directional stability is least,and improved course holding will result fromincreasing the rudder setting. The optimumrange of adjustment is easily found byexperiment.

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6.0 OPERATING HINTS

Unlike sailing yachts, power vessels do notgenerally suffer with violent changes in trim,and thus, provided the operating instructionsare carefully followed, extremely good courseholding performance will result in all weatherconditions.

Sailing yachts are very different since ingusting wind conditions violent changes in trimoften occur. When a yacht is sailing badly outof balance, sudden gusts will generally cause itto luff violently to windward. When handsteering, the tendency is overcome by applyingsufficient weather helm to maintain the originalheading. The Autohelm 5000’s automaticweather helm compensation circuit however, isintended only to take account of the gradualchanges in standing helm that typically occurwhen passage making due to changing windconditions.

When a sudden change in helm balanceoccurs the automatic compensation circuit willtake approximately one minute to restore theoriginal heading. In gusty conditions the coursewill tend to meander particularly if the sails arebadly balanced. Significant improvement tocourse keeping can be obtained by ensuringthat sail balance is maintained.

Bear in mind the following important points.

: 0 00 notallow the yacht to heel excessive!y.

0 Ease the mainsheet traveller to leeward toreduce heeling and weather helm.

0 If necessary reef the mainsail a little early.

It is also worth mentionina the more obviousand that is that an autopilot cannot anticipate.Sailing downwind in breaking seas needsparticular care.

One should avoid sailing under autopilotwhen the wi‘nd.is dead astern. Ideally, the windshould be brought at least 30 degrees towardsthe beam, and in breaking seas it is often betterto remove the mainsail altogether and to sailunder boomed out headsail alone.

Providing you ensure that your vessel isproperly canvassed for the prevailingconditions, your Autohelm 5000 will be capableto sailing you through gale force winds.Moreover, it is at times like this that it willendear itself most of all by leaving you freshand alert to sail in safety.

Passage making under automatic pilot is awonderful experience that can easily lead youinto the temptation of relaxing permanentwatch-keeping. This must be avoided howeverclear the sea ahead may appear to be.Remember, a large ship can cover two miles infive minutes - just the time it takes to brew acup of coffee!

7.0 ROUTINE MAINTENANCE

The autooilot is one of the most used andhardest working items of equipment on boardand, therefore, must receive its fair share ofattention and routine maintenance. The workingparts of the drive unit and the control unit aresealed and lubricated for life during manufactureand do not need servicing

Regular inspection and routine maintenanceof the installation is recommended in thefollowing areas:

1 Check tension and alignment of the drivechain and lubricate with a good qualitywaterproof light grease.

2 Check for the development of excessive lostmotion (backlash) in the steering gear andcorrect if necessary. Lost motion at the wheelshould not exceed 5% of the total wheelmovement from lock to lock.

3 Check that all inter-connecting cable socketsare fully tightened and free from corrosion.

4 Check that external waterproof sockets arecapped when not in use and periodicallyspray with WD40 (or similar) to protect fromcorrosion. ..

5 Check that the power supply cableconnections are tight and free fromcorrosion.

The Autohelm 5000 has an advanced micro-electronic circuit requiring special equipmentand knowledge to service. In the unlikely eventof failure occuring in any part of the system youare advised to contact your nearest appointedService Agent who will provide you withcompetent and efficient service.

Nautech Limited, Anchorage Park, PortsmouthHampshire PO3 5TD, England. Telephone (0705) 693611

Fax (0705) 694642, Telex 86384 NAUTEC G