Existing Sensors - Garmin Apollo CNX80 Installation Manual

Installation Procedures
not meet the acceptable field-of-view requirement above but have been evaluated by the FAA and
determined to be acceptable.
If the CNX80 installation is outside the acceptable field-of-view and the aircraft type is not
listed in Appendix E it does not mean that the installation is unacceptable – the FAA has
not yet evaluated it. The installation can be completed and the aircraft returned to service
pending an FAA evaluation of the installation, provided it is placarded "GPS LIMITED
TO VFR USE ONLY" in clear view of the pilot. IFR VOR/LOC/GS operations are still
permitted in this instance.
Contact Garmin AT for guidance on how to proceed in this case.
2.5.2 E
XISTING
When the CNX80 is installed with external sensors, these sensors must be installed in accordance with the
manufacturer's data. This manual does not provide information for the installation of specific external
sensors.
The CNX80 can accept data from multiple altitude, heading, and baro correction sources. If multiple
sources are used, the CNX80 will accept data as described below.
2.5.2.1 Multiple Altitude Sources
The CNX80 can accept altitude from an RS232 altitude encoder, fuel/air data computer (FADC), ARINC
429 air data computer (ADC), an SL70/SL70R transponder, and another CNX80.
If multiple sources of altitude data are supplied to the CNX80, only valid data from the highest priority
source is used (input priority cannot be configured). If the highest priority source becomes unavailable,
data is taken from the next-highest priority source. The priorities of the altitude sources are as follows
(from highest to lowest):
1. ARINC 429 ADC
2. FADC
3. RS232 Altitude Encoder
Although the CNX80 can be configured to accept data from an RS232 altitude encoder on
different ports, the CNX80 cannot accept data from two RS232 altitude encoders.
4. SL70/SL70R Transponder that receives Gray code altitude
Altitude data received from a second CNX80 will also be derived from one of the above
sources. Data received on the CNX80 cross-talk input is treated as if it is received directly
from the source that is supplying altitude to the second CNX80. If the direct input and the
CNX80 cross-talk input have the same priority, data from the direct input is used.
2.5.2.2 Multiple Heading Sources
The CNX80 can accept heading from an ARINC 429 Heading Source, an FADC or an XYZ synchro
source.
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ENSORS
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Apollo CNX80 Installation Manual