Garmin Approach G5 - GPS-Enabled Golf Handheld, Install Manual & Pilot'S Manual

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Garmin G5 Install Manual & Pilot's Guide 190-02072-00 Rev. E
11
Unit Installation
Installation Manual
Pilot's Guide
Appendix
Index
1.2.2.2.2 Can B
uS
w
irinG
Wiring used for the CAN bus should be shielded twisted-pair cable, MIL-C-27500 or
equivalent. 22 AWG or larger wire is recommended for physical robustness and ease
of installation. The shields for each CAN bus wire segment should be interconnected,
forming a continuously connected shield from one end of the CAN bus to the other
(Figure 1-6). At a minimum, the CAN bus shield should always be grounded to the
device connector backshells at the two extreme ends of the bus, but it is recommended
to also ground the shield at all other devices on the CAN bus.
CAN-H AND CAN-L WIRING SHOWN IS TWISTED SHIELDED PAIR
CAN BUS TERMINATION
CAN-H
CAN-L
SHIELD GROUND
CAN BUS TERMINATION
CAN-H
CAN-L
SHIELD GROUND
SHIELD GROUNDED AT CAN BUS TERMINATIONS, REQUIRED
DAISY-CHAINED
LRU ON CAN BUS
CAN-H
CAN-L
SHIELD GROUND
SHIELD GROUNDED AT EACH
DAISY-CHAINED LRU, RECOMMENDED
Figure 1-6 CAN Bus Shield Grounding
For proper CAN bus operation, it is important for all devices on the CAN bus to share
a common power ground reference. Connect all LRU power ground pins to a single
common ground point - do not use local ground points or use the aircraft structure as
a ground return path.
1.2.2.2.3 Can B
uS
t
ermination
At each of the two extreme ends of the CAN bus backbone, a 120
Ω
resistor is
installed to terminate the bus. Separate resistors are not required, termination resistors
are provided either within the LRUs themselves, or via termination adapters that plug
into an LRU’s CAN connection.
• The GAD 29, GMU 11, GPS 20A, and G5 installation kits each provide a
9-pin termination adapter that provides CAN bus termination when attached
between the LRU and the cable assembly. The termination adapter contains
a 120
Ω
resistor that is connected between pins 1 and 2 (Figure 1-7).