Garmin GTX 327, Руководство по установке

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GTX 327 Installation Manual Page 4-3
190-00187-02 Revision K
4.2 Altitude Functions
Parallel gray code altitude inputs are considered active if either the voltage to ground is < 1.9 V or the
resistance to ground is < 375
Ω
. These inputs are considered inactive if the voltage to ground is
11-33 Vdc. Refer to Figure C-3 for parallel gray code and serial data altitude interconnection. Carefully
check encoder input lines for correct connection after wiring is complete.
NOTES
The GTX 327 contains internal altitude code line isolation diodes to prevent
the unit from pulling the encoder lines to ground when the transponder is
turned off.
If two separate altimeters are connected to the GTX 327, one providing
parallel gray code and the other, serial data, the unit selects only one for use
at a time, with serial data input receiving the highest priority.
For altimeters that can be connected in both serial data and parallel gray code
format, such as the Garmin GAE 43 (Garmin P/N 013-00066-00), select one
or the other but not both wiring connections.
When connecting two GTX 327 transponders to a GPS, the unit can only
receive RS-232 serial data from one unit at a time. Use a DPDT switch for
connecting both serial data and External Standby Select. Refer to Figure
C-3.
4.2.1 Altimeter Inputs
Table 4-4. Encoded Altitude Pin Assignments
Pin Name Pin Number I/O
ALTITUDE D4 18 In
ALTITUDE A1 3 In
ALTITUDE A2 5 In
ALTITUDE A4 6 In
ALTITUDE B1 9 In
ALTITUDE B2 11 In
ALTITUDE B4 12 In
ALTITUDE C1 10 In
ALTITUDE C2 4 In
ALTITUDE C4 7 In
ALTITUDE COMMON SIGNAL GROUND 13 or 25* --
RS-232 IN 2 19 In
* Altitude Common may be connected to pin 13 or 25. See Note 10 on Figure C-1, and Note 7 on
Figure C-2.