Trio Avionics EZ Pilot - v 1.9 - Manual (Page 8)

4
3. Control and Display Unit
The control and display unit is designed to fit in a standard 3 1/8 inch instrument cutout in the
instrument panel and requires approximately a 3 inch clearance behind the instrument panel.
The unit is powered from the airframe +12V DC system. All controls are located on the front
panel.
This unit contains all of the controls and displays that are required for autopilot mode
selection, display data selection, servo power control, setting CRS direction and INT angle
selection.
3.1 Switch Function and Operation
3.1.1 ON/OFF Switch
The ON/OFF switch controls
application of aircraft power to the EZ
Pilot. In the OFF position the EZ Pilot
is completely disconnected from the
aircraft control system. On power up
the display presents a logo and the
current EZ Pilot firmware code version
(or a customized screen) and sets
several default conditions as follows:
Upon power up the TRK mode is
selected and the
TRK LED is illuminated. This mode is
not fully operational until valid GPS
data is available. When GPS is
unavailable for seven seconds, or after
initial power up, the display will default to a flashing
"NO GPS" message. In this
condition the autopilot may still be used to provide a wing leveler function and the L-R
switch can be used to initiate turns to the left or right. Once GPS data is present and
validated, full navigation function is available.
Servo power is initially off on power up. The Servo Power Switch must be pressed
momentarily to activate the system servo for either normal navigation or wing leveler
functions. When the SERVO POWER LED is not illuminated the servo motor is
completely disconnected from the aircraft control system.
3.1.2 Mode Switch
The MODE switch controls the selection of the TRK (track), CRS (course) and INT
(intercept) modes. The default mode during power up is TRK.
Pressing the MODE switch momentarily advances the mode from TRK ---> CRS ---> INT
and then back to TRK. The appropriate LED illuminates in each mode.
The automatic transition from the INT mode to the TRK mode is a function of the
L-R
Switch
LED
The MODE switch also provides the “AUTOMATIC COURSE REVERSAL” feature which does an automatic
servo engage and ground track reversal. Please paragraph 3.2.12 for operation instructions for this feature.
Also, the MODE switch function may be connected to an external switch (in lieu of the display dimming
function) to provide a remote method of changing the EZ Pilot mode setting. See paragraph 4.0 for additional
details.
Push Button
Switch