Trio Avionics EZ Pilot - v 2.3 - Manual (Page 33)

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the servo. Set the override force to a value that seems strong enough to give a fairly
good roll authority, but not so strong as to be difficult to override with the control stick.
Work toward setting the servo slip clutch to the minimum torque necessary to give
enough roll authority to handle a reasonable amount of turbulence.
Slip
Clutch Adjustment
If you tighten the clutch enough to exceed the maximum torque rating, you may hear a
loud clacking sound in the servo and the servo may disengage. This clacking happens
when the force pushing the gears apart exceeds the solenoid’s ability to hold the gear
train engaged. This is a redundant safety feature – just back off on the control nut a little
and recycle the power switch to re-engage the servo.
7.6 Adjustment of Servo Rotation Direction and Servo Neutral
With the autopilot now fully installed, it is necessary to perform a preliminary adjustment
to the servo neutral position. This procedure will set the neutral position and also
determine the direction of servo rotation for a left or right roll correction.
7.6.1 Setup Mode Entry
With the GPS receiver turned off, turn on the EZ Pilot power switch while
simultaneously holding down the DISPLAY pushbutton. Then release the
DISPLAY pushbutton. The EZ Pilot is now in the “setup” mode. Press the
SERVO button on the control head to engage the servo. You should hear the
solenoid engage the gears and you may see some brief movement of the
ailerons. The autopilot will now be in the “servo calibration” mode with the
SERVO POSITION screen displayed. If this is an LCD model, advance to the
servo positioning screen by pressing the mode button 1 time.
Note: In older systems it was sometimes necessary to reverse internal servo wiring and/or to
fly the aircraft several times, and adjust the servo push rod position several times, to accurately
fix the neutral position. The EZ Pilot incorporates an electronic method to “zero” the servo once
it has been properly installed. This setting is then stored in the autopilot permanent memory,
thus eliminating the need to perform repetitive mechanical adjustments to achieve an accurate
neutral position.