Autohelm Inboard Autopilots (ST6000 and ST7000 systems) Service ...

AutohelmUnsatisfactory Steering PerformanceIf the 5T7000 has been installed and set upin accordance with the instructions in theInstallation Manual it will provide excellentsteering performance over a wide range ofconditions.If performance drops but the autopilot is stillworking correctly, the following simplechecks should find the fault:-• Has a magnetic influence beenintroduced near the fluxgate compass? i.e.anchor, chain, radio equipment,loudspeaker, tools, generator etc. Checkthat the autopilot compass heading stillcorresponds with the steering compass.• Are all fuses intact, circuit breakersengaged?• Are all screw connections tight and freeof corrosion.• If the autopilot fails to hold course checkthe Rudder Gain level. Has it been changedfrom the initial sea trials level (check inInstallation Manual)?• If the vessel wanders check that theRudder Reference Transducer linkage issecure with no free play.Hydraulic Drive Units only:-• Check that all unions are tight and bleedsystem to remove air.Failure to DisengageThe mechanical drive actuators of theST7000 are designed to ‘Fail Safe’ — Whenpower is disconnected the drive unit willdisengage leaving the steering system freefor manual control.When Standby is selected the actuator willDisengage leaving the steering free.It is remotely possible that a fault coulddevelop which could cause the actuator toremain engaged even when Standby isselected. If this happens:-• DISCONNECT THE MAIN CIRCUITBREAKER TO THE AUTOPILOT — THESTEERING WILL IMMEDIATELY BE FREE.or• IN AN EMERGENCY THE ACTUATORCLUTCH CAN NORMALLY BEOVERRIDDEN BY TURNING THESTEERING WHEEL HARD.It is emphasised that this fault is extremelyunlikely and can be immediately correctedas described.If preferred a separate Override switch canbe fitted close to the steering position whichwill break the actuator clutch drive forEmergency Use.SafetyPassage making under autopilot is avery pleasant experience which can leadto the temptation of relaxing permanentwatch. This must always be avoided nomatter how clear the sea may appear tobe.It is the responsibility of the skipper toensure the safety of his vessel at alltimes by careful navigation and that allcrew members are familiar with theprocedures required to engage anddisengage the autopilot.When searoom is restricted, a crewmember must be close to a control unitat all times if under Autopilot control.On Power craft permanent watch shouldbe maintained at the steering stationwhen at speed with the Autopilotengaged.SeaTalk Service Manual 9