Simrad AUTOPILOT SYSTEM AP50 - Manual (Page 83)

Installation
20221032B
81
The feedback unit has an external ground terminal an must have
a proper ground connection to the hull. The grounding wire
should be as short as possible and at least 10 mm wide.
The RF14XU can be powered either from the rudder angle
indicator supply (19-40V DC) or directly from the autopilot
junction unit. If a rudder angle indicator is connected, the
RF14XU is powered from the rudder angle indicator supply. If
the rudder angle indicator voltage disappears, or rudder angle
indicator is not connected to the RF14XU, the feedback unit is
powered directly from the autopilot. The change over is done
automatically.
Note ! If RF14XU is connected to rudder angle indicators, and the
indicators are powered from an unfiltered 24V supply, the
enclosed 470uF capacitor should be connected across the
supply. Without the capacitor, a deviation may occur between
the autopilot feedback midposition reference and that of the
rudder angle indicator(s). Scaling of rudder angle of indicators
may be required. Refer to Figure 4-9, note 2.
Cable
screen
Figure 4-8
Screen termination