EFD1000 E5 Dual Electronic Flight Instrument (EFI) Install Manual
DOCUMENT # 900-00041-001
PAGE 93-226
REVISION D
© Copyright 2019 Aspen Avionics Inc.
8.2.5.11
GPS Selected Output
Active low discrete output indicating GPS1 or GPS2 is the current coupled sensor on the
HSI.
GPS coupled: ................. Sinks to ground
GPS not coupled: ........... Open
Load Current: ................ 100ma maximum
8.2.5.12
ARINC 429 Output
The ACU transmits the following labels on P3 pins 4 and 5 for GPS receivers and
systems that require ARINC 429 magnetic heading and selected course.
Note- Except as shown in the wiring diagrams (Section 9) no ARINC 429 interface is
approved under the Aspen STC, and must be approved separately.
ARINC
Label
EFD Data
Rate
(ms)
100
Selected Course
200
320
Magnetic Heading
200
Table 8-8: ACU A429 Output
8.3
ACU2 Electrical Specifications (910-00004-10x only)
The ACU2 has the same interfaces as the ACU above on connectors J1/J2/J3 plus it adds the
following interfaces on connector J4.
8.3.1
Heading Synchro Out
The ACU2 will output a heading synchro (bootstrap) signal per ARINC 407 to external
equipment.
Heading Reference In:
Input Range: ...................... 17Vac to 30Vac
Frequency Range: .............. 300Hz to 5500Hz
Load: ................................. at least 68100 ohm
Heading Reference Out:
Output Voltage: ................. 17Vac to 30Vac (26Vrms nominal) into a 10000 ohm load
Frequency Range: .............. 350Hz to 450Hz
Load: ................................. 10000 ohm
Synchro Output:
Output Format: .................. V
X-z
= V
Ref
sin(
Ө
- 120⁰)
V
Y-Z
= V
Ref
sin(
Ө
+ 120⁰)
Output Range: ................... 0 to 11.8Vrms
The ACU2 will disable the heading reference output when an external reference of greater
than 18Vac is applied across pins 26V-REF-H and 26V-REF-C.
Heading Valid:
Open Collector output to the heading valid flag. It can sink up to 100mA to ground at
28Vdc.
