Trio Avionics EZ Pilot - v 1.9 - Manual (Page 27)

23
TRIO AVIONICS
P4EP2 XXXXXXXXX
NO GPS TURN
[--------X-------]
6.0 Installing the Control Head
The EZ Pilot control head mounts from the rear side of
the instrument panel. It is held in place by 4 ea. Number
6 screws. When mounted, the visible area is contained
within a standard 3-1/8 inch instrument cutout.
The autopilot system (including servo) normally draws
less than 1 amp of current from the 12 volt source.
While the unit is internally fused, it is strongly
recommended that an external fuse or circuit breaker be
provided to protect against the possibility of a short in the
wiring harness to the system. A three amp fuse or
breaker is recommended for the wire sizes
recommended in the installation procedures
.
Once the unit is installed, turn on aircraft power and
energize the control head using the POWER toggle
switch at the top of the faceplate.
The display will illuminate showing a brief message
that describes the software version contained within
the control head. Alternatively, it may present a
customized message (example – your name, aircraft
type and tail number) if you have customized the startup screen.
After a few seconds, the display will show a “NO
GPS” message. At this point, you should turn on
your GPS and move your aircraft to a position where
it will obtain reliable GPS signals. Once you enter a
flight plan into your GPS, and/or attain a groundspeed of several knots, you should observe
normal flight data similar to that shown in earlier pages of this manual.
6.1 Your GPS
If you do not get a proper display (once your GPS is turned on and has a clear view of the sky)
check the wiring connections between the GPS unit and the EZ Pilot. The signal input requires a
data input and a ground, and these must be wired as shown in the wiring diagram (Section 8.6).
Although GPS receivers generally conform to industry standards (NMEA 0183 for portables and
Aviation Data Link for most panel mount receivers) they do vary in the format of the output data
stream. This is especially true for older systems. Some do not put out enough information for
navigational purposes, as they were designed before it was realized that such outputs could be
useful to other devices. The EZ Pilot is compatible with most mainstream receivers. It scans and
analyzes the data and configures itself to process it so it is useful for navigation. If your receiver
does not provide data that the EZ Pilot recognizes, the autopilot display will present the message
“NO GPS”. You should notify the factory if you cannot sync to the signal. However, it is
important to check for the following:
1. Your GPS probably has a setup mode where you must enable the output. Some have
several possible output modes. The proper mode must be enabled for the GPS to
communicate with the autopilot. For the NMEA format the desired output is NMEA 0183
Rev 2.0 (or greater), 4800 baud rate, 8 data bits, no parity, 1 stop bit (8, N, 1). The
AVLINK is 9600 baud, 8 data bits, no parity, 1 stop bit (8, N, 1). Refer to your GPS user’s
manual for guidance.