![](https://pdfstore-manualsonline.prod.a.ki/pdfasset/8/48/8485f71e-19db-4add-88d1-4f240358ca08/8485f71e-19db-4add-88d1-4f240358ca08-bg60.png)
Chapter 5: Installing the ST4000+ 81
5 Installing the ST4000+
5.6 Rudder position sensor (wheel pilot option)
If you connect the optional Raymarine rudder position sensor (part
number: M81105) to your wheel drive system, the autopilot will use
the accurate rudder position information to improve performance.
The ST4000+ will also use this information to show the true rudder
angle in Standby and Auto modes.
Note: You must fit a rudder position sensor to your wheel drive
system if there is significant lost motion in your steering system or if
you are installing the wheel drive on a hydraulic steering system.
The rudder position sensor connects directly to the boat’s tiller arm or
quadrant. Installing the sensor involves five main steps:
• ensuring correct alignment
• securing the sensor to the boat
• attaching the sensor to the tiller arm
• checking alignment
• connecting to the control unit
Ensuring correct alignment
CAUTION:
Take care to ensure correct rudder sensor alignment. If the
sensor is not correctly aligned, the autopilot system will not
perform accurately.
Vertical alignment
When viewed from the front (as shown in the illustration below), the
connecting rod should be as level as possible, so the ball-joints at each
end are level. It should also remain parallel to the tiller arm’s plane of
rotation at all times.
Note: If misalignment exceeds +/-5° the ball-joints will bind or fail.