GmbH
ATTITUDE AND HEADING REFERENCE SYSTEM
(AHRS)
LCR-92 PART NO. 141450-XXXX
LCR-92 PART NO. 141852-XXXX
LCR-92 PART NO. 124210-XXXX
LCR-92 PART NO. 142300-3200
INSTALLATION / MAINTENANCE INSTRUCTION
JUNE 1995
REVISION 4, NOVEMBER 1998
LITEF DOCUMENT NO. 141450-0000-840
GmbH
ATTITUDE AND HEADING REFERENCE SYSTEM
LCR-92 PART NO. 141450-XXXX
LCR-92 PART NO. 141852-XXXX
LCR-92 PART NO. 124210-XXXX
LCR-92 PART NO. 142300-3200
INSTALLATION / MAINTENANCE INSTRUCTION
June 1995
Revision 4, November 1998
LITEF GmbH
Loerracher Str. 18, D–79115 Freiburg Tel.: (0761) 49010
E 06.1995 LITEF GmbH
All rights reserved, including the right to copy, distribute and translate. No part of this document may be reproduced without the express prior written consent of LITEF,
not even for archive purposes and may e.g. not be made use of, reproduced or disseminated by use of electronic means.
LITEF DOCUMENT No: 141450–0000–840
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
To :
HOLDERS OF INSTALLATION / MAINTENANCE INSTRUCTION
( LCR-92 ) PART NO. 141450-0000-840
REVISION 4, DATED NOVEMBER 1998
The changes incorporated with this revision are :
(1).................. Complete re-working of the technical content (all text pages and illustrations)
and the re-structuring of the layout of the IMI,
with the main points highlighted as follows :
(2).................. Incorporating both FX-125 and FX-220 MSUs into one figure (previously two
figures).
(3).................. Modifications to figure 4 to give a clear interpretation to the technician (when installing
the MSU).
(4).................. Addition of a CalPROM drawing.
(5).................. Modifications to figure 15 to give a clear interpretation to the technician (when installing
and working on the cable and / or cable connector).
(6).................. System wiring tables simplified to facilitate ease of reading.
(7).................. Alterations to figures 13 and 14.
(8).................. Addition of Section 5.
(9).................. Addition of Appendix 1.
(10)................ PNs removed from INSTALLATION / MAINTENANCE INSTRUCTION title at the
top of each page,
and
(11)................ many minor alterations too numerous to be listed here.
HIGHLIGHTS
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GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
INTRODUCTION
The LCR-92 is an Attitude and Heading Reference System (AHRS). It combines the functions of a
vertical gyro, a gyro stabilized magnetic compass and 3 rate gyros within one single unit. The
LCR-92 is a strapdown system, in which the sensors - fiber optic gyros (FOG) and level sensors are literally “STRAPPED” to the aircraft structure. The AHRS provides attitude and heading data,
as well as information about the dynamics of the aircraft to the cockpit displays, the flight control
system and other users in the aircraft. The principal data provided by the LCR-92 AHRS is :
- pitch angle
- roll angle
- magnetic heading
- angular rates around the aircraft axes
The LCR-92 system consists of the following components :
- AHRU (Attitude and Heading Reference Unit)
- MSU CalPROM
- Flux-Valve
- CCU (Compass Controller Unit, optional)
AHRU
The AHRU is the main AHRS component, containing the sensors (FOG and level sensors), processor, power supply, and interfaces to the users.
MSU CalPROM
The MSU CalPROM is an external detachable device, located at the AHRU front panel. It stores the
aircraft specific information necessary to compensate the flux-valve errors and the misalignment of
the mounting tray.
Flux-Valve
The flux-valve provides the AHRU with information about the earth’s magnetic field. In an aircraft
it is usually fitted in an area selected to minimize interference by ferromagnetic materials and magnetic fields generated by the aircraft.
CCU
The compass control functions can be integrated into the cockpit design or, as an option, be installed
as a separate Compass Control Unit. The LITEF Compass Control Unit is an optional component
which allows the AHRU to be decoupled from the flux-valve and to set the system to any desired
heading. The system then operates in the DG mode with a heading performance equivalent to a free
directional gyro.
INTRODUCTION
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
PREFACE
THE LCR-92 INSTALLATION / MAINTENANCE MANUAL
IS COMPILED OF FIVE MAIN SECTIONS, NAMELY :
SECTION 1
installation instructions
SECTION 2
description and operation
SECTION 3
testing and troubleshooting
SECTION 4
removal and installation
SECTION 5
storage / packaging / transportation
AND AN APPENDIX :
APPENDIX 1
RTCA/DO-160C environmental
qualification form
AND WITH EACH SECTION BEING DIVIDED INTO PARAGRAPHS
AND SUB-PARAGRAPHS
For a more comprehensive listing refer to the table of contents
PREFACE
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
RECORD OF REVISIONS
REV
NO.
ISSUE
DATE
DATE
INSERTED
1
2
3
4
July 1996
October 1996
Nov. 1996
Nov. 1998
incorporated
incorporated
incorporated
incorporated
BY
REV
NO.
ISSUE
DATE
DATE
INSERTED
REVISIONS
BY
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
RECORD OF TEMPORARY REVISIONS
TEMPORARY
REV NO.
PAGE NO.
ISSUE DATE
BY
DATE
REMOVED
TEMPORARY REVISIONS
BY
Page 1/2
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
SERVICE BULLETIN LIST
SERVICE
BULLETIN
NO.
SUBJECT
MANUAL
REVISION
NO.
MANUAL
REVISION
DATE
141450-0000840-001
Power Supply Module
1
July 1996
141450-0000840-002
DO 160C, section 20 “ RF Susceptibility
1
July 1996
141450-0000840-003
DO 160C, section 20 “ RF Susceptibility
(supersedes SB no. 141450-0000-840-002)
1
July 1996
141450-0000840-004
(issue 2)
Software update and internal modification to
the AHRU (LCR-92 P/N 124210-XXXX) to
enable the environmental HIRF category to
be realized
3
Feb. 1998
141450-0000840-005
Software update and internal modification to
the AHRU (LCR-92 P/N 141450-XXXX) to
enable the environmental HIRF category to
be realized
3
Nov. 1996
141450-0000840-006
Software update and internal modification to
the AHRU (LCR-92 P/N 141852-XXXX) to
enable the environmental HIRF category to
be realized
3
Nov. 1996
141450-0000840-007
DELETED: RELEVANT INFORMATION
USED TO PUBLISH SB-004, ISSUE 2
–
–
141450-0000840-008
Hardware update to the Interface Module to
accomodate for variations of the flux-valve
output voltage level.
–
–
SERVICE BULLETIN LIST
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
LIST OF EFFECTIVE PAGES
SECTION
Title Page
Introduction
Preface
Record of Revisions
Record of Temporary Revisions
Service Bulletin List
List of Effective Pages
List of Illustrations
List of Tables
Table of Contents
Abbreviations
Frontispiece
Title Page, Section 1
Installation Instructions
Title Page, Section 2
Description and Operation
Title Page, Section 3
Testing and Troubleshooting
Title Page, Section 4
Removal/Installation
Title Page, Section 5
Storage / Packaging / Transportation
Appendix 1
RTCA/DO-160C Environmental
Qualification Form
PAGE
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1/2
1/2
1/2
1/2
1 through 4
1/2
1/2
1 through 52
1 through 8
1 through 10
1 through 2
1 through 6
1 through 2
EFFECTIVE PAGES
DATE
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GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
LIST OF TABLES
No.
TITLE
PAGE
SECTION 1
1
Connectors Configuration
4
2
Power Consumption
5
3
Mounting Discretes
8
4
DG-Mode Logic Selection Discretes
8
5
Source / Destination Discretes
9
6
Analog Yaw Rate Scale Factor Discretes
9
7
Control Discretes
10
8
Digital Binary Outputs
13
9
Digital Binary Outputs (cont.)
14
10
Digital Binary Outputs (cont.)
14
11
Digital BCD Outputs
15
12
Discrete Flag Warn Signals
16
13
Synchro Outputs
18
14
2-Wire AC Outputs
19
15
Digital Self-Test Outputs
21
16
Analog Self-Test Outputs
21
17
Discrete Self-Test Outputs
22
18
System Wiring (9 sheets)
39
19
AHRU / MSU Wiring
47
SECTION 2
1
Failure Transmission Frame (2 sheets)
6
SECTION 3
1
Maintenance Discrete Outputs (Label 350)
3
2
Maintenance Discrete Outputs (Label 351)
4
3
Maintenance Discrete Outputs (Label 352)
5
4
Maintenance Discrete Outputs (Label 353)
6
TABLES
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
LIST OF ILLUSTRATIONS
No.
TITLE
introduction
LCR-92 Attitude and Heading Reference System Frontispiece
PAGE
SECTION 1
1
Interface Diagram LCR-92
7
2
Examples of a typical wiring of a discrete output, e.g. AHRU Warn
17
3
AHRU Outline
28
4
KMT 112 MSU Outline and Mounting Diagram
29
5
FX-120 MSU Outline and Mounting Diagram
30
6
FX-125 / FX-220 MSU Outline and Mounting Diagram
31
7
CCU Outline and Mounting Diagram
32
8
Tray Outline - Without Fan (P/N 124260)
33
9
Tray Outline - With Fan (P/N 140691)
34
10
Tray Outline - Without Fan (P/N 124260-5000)
35
11
Tray Outline - With Fan (P/N 140691-5000)
36
12
CalPROM Outline
37
13
Interconnection Diagram CCU, LCR-92
48
14
Interconnection Diagram Ground Discrete Reference
49
15
Shield termination of connectors using Metal Backshell / Strain Relief method
50
16
Bonding Strap for the installation of AHRU P/N 141852-3211
51
SECTION 3
1
Typical LCR-92 AHRS Installation
2
SECTION 5
1
Packaging of Electrostatic Discharge Sensitive Devices
3
2
Electrostatic Discharge Sensitive Device Labels (typical examples)
4
3
Location of Identification Markings
5
ILLUSTRATIONS
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
TABLE OF CONTENTS
PARAGRAPH
PAGE
SECTION 1 INSTALLATION INSTRUCTIONS
1
INSTALLATION DATA
1
Dimensions and Weight
4
Location
4
Connectors
4
Power
5
2
WIRING
5
3
SIGNAL INPUT
6
Program Pins
6
Parity
8
Azimuth Mounting Discretes
8
DG-Mode Logic Selection
8
Source Destination Identifier
9
Analog Yaw Rate Scale Factor Selection
9
Turn Rate Select
9
Control Discretes
10
MSU Calibration Control Switch
10
Digital Inputs
10
ARINC 429 Inputs
10
RS-422 Input
11
Analog Inputs
4
11
SIGNAL OUTPUT
12
Digital Outputs
12
ARINC 429 Outputs
12
RS-422 Output
15
Discrete Flag Warn Signals
16
Analog Outputs
18
Synchro Outputs
18
2-Wire AC Outputs
19
2-Wire DC Outputs
19
CONTENTS
Page 1
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
PARAGRAPH
PAGE
Self-Test Outputs
21
5
COOLING REQUIREMENTS
23
6
AHRU ALIGNMENT REQUIREMENTS
23
Installation Tray
7
8
9
23
FLUX VALVE (MSU) CALIBRATION
23
General
23
Index Error
24
Calibration Procedure
24
MSU Calibration Procedure/Checklist
26
OUTLINE DRAWINGS
27
AHRU
28
MSU, Bendix/King
29
MSU, Honeywell (FX-120)
30
MSU, Honeywell (FX-125 / FX-220)
31
Compass Control Unit
32
Tray, without Fan (P/N 124260)
33
Tray, with Fan (P/N 140691)
34
Tray, without Fan (P/N 124260-5000)
35
Tray, with Fan (P/N 140691-5000)
36
CalPROM
37
SYSTEM WIRING
38
J1 (Power Supply)
39
J2 (Fan Supply)
39
J3 (Synchro) (only AHRU / P/N 124210-2011)
40
J3 (Synchro) (only AHRU / P/N 141XXX-2XXX)
41
J3 (Synchro) (only AHRU / P/N 141852-32XX)
42
J3 (Synchro) (only AHRU / P/N 141XXX-30XX and
141XXX-31XX)
43
J4 (I/O)
(only AHRU / P/N 124210-XXXX)
44
J4 (I/O)
(only AHRU / P/N 141450-XXXX and
141852-XXXX)
45
J5 (CalPROM)
47
CONTENTS
Page 2
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
PARAGRAPH
PAGE
SECTION 2 DESCRIPTION AND OPERATION
1
GENERAL
1
2
PURPOSE OF EQUIPMENT
1
3
LEADING PARTICULARS
1
4
DESCRIPTION
1
5
Location of Units in Aircraft
1
Outline and Mounting Drawings
1
AHRU
1
MSU
2
CCU (optional)
2
MODES OF OPERATION
2
Alignment
3
General
3
Alignment Phase 1
3
Alignment Phase 2
3
Normal Mode
6
4
Slaved Mode
4
DG-Mode
4
MSU Calibration Mode
4
Maintenance Mode
4
General
4
Failure Logging and Malfunction Storage
5
Output of the Failure History and Elapsed Time
5
POWER INTERRUPTIONS
8
General
8
Short Power Interrupt
8
Long Power Interrupt
8
SECTION 3 TESTING AND TROUBLESHOOTING
1
GENERAL
1
2
MAINTENANCE DISCRETE OUTPUTS
3
CONTENTS
Page 3
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
PARAGRAPH
3
PAGE
INITIAL INSTALLATION OF AN AHRU FAULT FINDING
CHECK-LIST
7
AHRS EQUIPPED WITHOUT A SYNCHRO CARD
7
Step 1 : EFIS does not display any data
7
Step 2 : Heading and Attitude Flags Displayed (invalid data)
7
Step 3 : Heading Flag Displayed (invalid data)
7
Step 4 : Attitude Flag Displayed (invalid data)
8
Step 5 : Heading Check
8
Step 6 : Attitude Check
8
Step 7 : CCU Check
8
Step 8 : Self-Test
8
Step 9 : Cal-Mode Switch
9
Step 10 : On Ground / In Air Switch
9
AHRS EQUIPPED WITH A SYNCHRO CARD
4
9
LITEF LCR-92 LEVEL 1 TEST SET
10
SECTION 4 REMOVAL / INSTALLATION
1
GENERAL
1
2
REMOVAL OF AHRU
1
3
INSTALLATION OF AHRU
1
SECTION 5 STORAGE / PACKAGING / TRANSPORTATION
1
GENERAL
1
2
STORAGE
1
3
PACKAGING
1
Special Packaging Requirements
4
TRANSPORTATION
2
2
APPENDIX 1 RTCA/DO-160C ENVIRONMENTAL
QUALIFICATION FORM
CONTENTS
Page 4
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
LIST OF ABBREVIATIONS
The following are a list of abbreviations that are used in the text:
AC
A/C
AF
AHRS
AHRU
ARINC
ATT
BIT
CalPROM
CCU
DC
DG
DITS
EEPROM
FOG
GND
HDG
HIL
I/F
MSU
MTBF
N/A
NCD
RAM
P/N
PROM
RF
RTCA
S/N
SAV
SDI
SSM
TR
TSO
UUT
YR
Alternating current
Aircraft
Audio Frequency
Attitude and Heading Reference System
Attitude and Heading Reference Unit
AERONAUTICAL RADIO, INCORPORATED
Attitude
Built-In Test
Calibration PROM
Compass Control Unit
Direct Current
Directional Gyro
Digital Information Transfer System
Electrically Erasable Programmable Read Only Memory
Fibre Optic Gyro
Ground
Heading
Hardware-In-the-Loop (test method)
Interface
Magnetic Sensor Unit
Mean Time Between Failures
Not Applicable
No Computed Data (ARINC 429)
Random Access Memory
Part Number
Programmable Read Only Memory
Radio Frequency
Radio Technical Commission for AERONAUTICS
Serial Number
Standard Applied Voltage
Source Destination Identifier (ARINC 429)
Sign Status Matrix (ARINC 429)
Turn Rate
Technical Standard Order
Unit Under Test
Yaw Rate
ABBREVIATIONS
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November 1998
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INSTALLATION / MAINTENANCE INSTRUCTION
FRONTISPIECE
AHRU
FRONT VIEW of AHRU showing connectors
MSU CalPROM
MSU (FLUX-VALVE)
OUTLINE DRAWINGS NOT TO SCALE
CCU (Optional)
LCR–92 Attitude and Heading Reference System Frontispiece
FRONTISPIECE
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November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
SECTION 1
INSTALLATION INSTRUCTIONS
LITEF DOCUMENT No: 141450–0000–840
TITLE PAGE SECTION 1
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
1
Installation Data
This section contains information that will aid in the installation of the Attitude and Heading Reference
System (AHRS, frontispiece). The dash number formats of the various versions of LCR-92 are as shown
below, and the ancillary equipment applicable to the various systems is laid out in the configuration on
page 3.
P/N 124210-XXXX
P/N 141450-XXXX
P/N 141852-XXXX
P/N 142300-XXXX
Standard Performance AHRU
High Performance AHRU
Standard Performance AHRU
Standard Performance AHRU
0
1
2
0
1
2
0
1
2
1
2
3
Basic Software Version
Software Upgrade 1
Software Upgrade 2 (except for P/N
124210-XXXX)
Basic Hardware Version
Improved Hardware for DO-160C Sec. 20 Cat. W
Improved Hardware for DO-160C Sec. 20 Cat. Y
(except for P/N 124210-XXXX)
Bendix/King Flux-Valve Interface
Honeywell Flux-Valve Interface
Honeywell Flux-Valve Interface and 167 mV/deg
two wire AC Output for Version -32XX only
Digital Interface only
Digital and Synchro Interface with 12 bit
A/D attitude resolution
Digital and Synchro Interface with 16 bit
A/D attitude resolution (except for P/N
124210-XXXX)
LCR-92 (P/N124210) CONFIGURATION
Unit
Part No. (Bendix/King Flux Valve Interface)
Attitude Heading and Reference
Unit
P/N 124210-1011
Digital Interface
P/N 124210-2011
Digital & Synchro Interface (12
bit D/A attitude resolution)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 1
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
LCR-92 (P/N141450) CONFIGURATION
Unit
Part No. (Bendix/King Flux Valve Interface)
Attitude Heading and Reference
Unit
P/N 141450-1000/1011/1022
Digital Interface
P/N 141450-2000/2011/2022
Digital & Synchro Interface (12
bit D/A attitude resolution)
P/N 141450-3000/3011/3022
Digital & Synchro Interface (16
bit D/A attitude resolution)
Part No. (Honeywell Flux Valve Interface)
P/N 141450-1100/1111/1122
Digital Interface
P/N 141450-2100/2111/2122
Digital & Synchro Interface (12
bit D/A attitude resolution)
P/N 141450-3100/3111/3122
Digital & Synchro Interface (16
bit D/A attitude resolution)
LCR-92 (P/N141852) CONFIGURATION
Unit
Part No. (Bendix/King Flux Valve Interface)
Attitude Heading and Reference
Unit
P/N 141852-1000/1011/1022
Digital Interface
P/N 141852-2000/2011/2022
Digital & Synchro Interface (12
bit D/A attitude resolution)
P/N 141852-3000/3011/3022
Digital & Synchro Interface (16
bit D/A attitude resolution)
Part No. (Honeywell Flux Valve Interface)
NOTE :
P/N 141852-1100/1111/1122
Digital Interface
P/N 141852-2100/2111/2122
Digital & Synchro Interface (12
bit D/A attitude resolution)
P/N 141852-3100/3111/3122
Digital & Synchro Interface (16
bit D/A attitude resolution)
P/N 141852-3200/3211/3222
P/N 142300-3200
Digital & Synchro Interface (16
bit D/A attitude resolution), and
167 mV / deg two wire AC Output
P/N 142300-3200 AHRU is identical to P/N 141852-3200 with the exception
of the nameplate and the deletion of TSO C4c.
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 2
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
CONFIGURATION FOR EQUIPMENT THAT IS APPLICABLE
EITHER TO THE :LCR-92 (P/N124210) CONFIGURATION
or
LCR-92 (P/N141450) CONFIGURATION
or
LCR-92 (P/N141852) CONFIGURATION
Magnetic Sensor Units (MSU)
(Flux-valve)
P/N 1071-1052-00*
Bendix/King KMT 112
P/N 620359**
Honeywell FX-120
P/N 656520**
Honeywell FX-125 / 656520
P/N 2594484**
Honeywell FX-220 / 2594484
MSU Calibration PROM
P/N 124282-0000
Installation Kit
(Mating Connector Set)
P/N 124284-0000
P/N 124284-1100
AHRU Mounting Tray
Compass Controller Unit
(CCU, optional)
Installation Kit for CCU
(if fitted)
NOTE
P/N 124284-2100
(AHRU with Synchro Interface) plastic
(AHRU with Synchro Interface and
Bonding Strap) metal
(AHRU with Synchro Interface) metal
P/N 124285-0000
P/N 124285-2100
(AHRU without Synchro Interface) plastic
(AHRU without Synchro Interface) metal
P/N 124260-0000
(excluding Fan)
P/N 124260-5000
(excluding Fan)
P/N 140691-0000
(including Fan)
P/N 140691-5000
(including Fan)
P/N 140855-0010
(5V Lighting, black panel)
P/N 140855-0020
(28V Lighting, black panel)
P/N 140855-0030
(5V Lighting, grey panel)
P/N 140855-0040
(28V Lighting, grey panel)
P/N 141468-0000
* to be ordered directly from Bendix-King
** to be ordered directly from Honeywell
Systems with P/N 141450-3111 and P/N 141852-3111 shall be installed with
tray P/N 124260-5000 or P/N 140691-5000 ONLY.
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 3
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
1.1
Dimensions and Weight
Dimensions
Configuration
AHRU, see Fig. 3
MSU, see Figs. 4 to 6 incl.
Weight
with synchro interface
less than 2.5 kg (5.5lbs)
without synchro
interface
less than 2.1 kg (4.6lbs)
Bendix/King
Honeywell
Honeywell
Honeywell
KMT112 ; 136 gms (0.3lbs)
FX-120 ; 680 gms (1.5lbs)
FX-125 ; 680 gms (1.5lbs)
FX-220 ; 680 gms (1.5lbs)
0.4 kg (0.8lbs) max
CCU, see Fig. 7
Mounting Tray, see Figs. 8 to 11
with cooling fan
approx. 0.5 kg (1.1lbs)
without cooling fan
approx. 0.3 kg (0.6lbs)
MSU CalPROM, see Fig. 12
1.2
less than 35 gms (0.08lbs)
Location
The AHRU is generally located in the aircraft’s equipment bay electronics rack, and its major axes must
be parallel or perpendicular to the major axes of the aircraft. The CCU is installed on a panel in the
cockpit. The MSU should be located as far as possible from all sources of local magnetic disturbances
such as engines, electrical cables or radio equipment. A wing tip or tail section location will usually be
satisfactory.
1.3
Connectors
The AHRU external connectors are Sub-Min-D type with metric M3 screw lock and having the
following pin configurations :
Connector
Function
Pins/Sockets
Connector type
Mating connector
J1
Power
15
HDC15M
HDC15F
J2
Fan Supply
9
HDC09F(not required)*
HDC09M(not required)*
J3
Synchro Output
44
DD44M
DD44F
J4
Input/Output
62
DD62M
DD62F
J5
MSU CalPROM
15
DD15F(not required)*
DD15M(not required)*
Table 1 Connectors Configuration
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 4
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
* No wiring is required for connector J2 (Fan Supply), and for connector J5 (CalPROM),because the
mating connectors are integral parts of the Mounting Tray with Fan and the CalPROM itself. If a Fan is
not used a plastic cap should be installed on connector J2. The metal block attached to the end of the
CalPROM retaining cable should be permanently affixed to the Mounting Tray with the two machine
screws provided.
The mating connectors with metric (M3) screw lock shall have metal or metallized plastic backshells.
The mating connector for the KMT 112 flux valve is Allied Signal P/N 030 2190 00
The CCU mating connector is made up of connector M83723/75R-1415N with M85049/52-1-14N
backshell.
1.4
Power
The AHRU is designed to operate from either one of two independent 28 VDC input power supplies.
The power consumption of the AHRU is listed below. The maximum power consumption of the optional
cooling fan is less than 3 Watts (which is not included in table 1 below). Maximum nominal current is 2.5
amperes (at 13 volts). At power on, surge currents can be as high as 10A for 10ms.
Power Consumption
Configuration
nom.
max.
without Synchro Interface
20 W
25 W
with Synchro Interface (max. load)
35 W
40 W
with Synchro Interface (high impedance load)
25 W
30 W
Table 2 Power Consumption
2
Wiring
Wiring details are provided in Table 18 at the end of this section.
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INSTALLATION / MAINTENANCE INSTRUCTION
3
Signal Input
In case of installation of dual systems do not connect the switched input discretes such as On
Ground / In Air, Maintenance, and Self Test in parallel. It is recommended that these inputs be kept
isolated by the use of relay contacts or optocouplers.
3.1
Program Pins
There are ten AHRU connector pins allocated for external program control as follows:
Pin
Function
J4-32
Program Pin Common
J4-14
Mount Position No. 1
J4-35
Mount Position No. 2
J4-34
SDI 1
J4-54
SDI 2
J4-12
DG-Mode Logic Select
J4-53
Yaw Rate Scale Factor Select No. 1
J4-11
Yaw Rate Scale Factor Select No. 2
J4-17
Turn Rate Select
J4-13
Parity (odd)
Program Pin Common is grounded inside the AHRU. External jumpers from the other program pins to
Program Pin Common or to 28 VDC for Turn Rate Select respectively, allow the AHRU to be
programmed to get various installations and customized functions as described on pages 8 and 9.
(Program Pin Common should not be grounded to aircraft system ground).
An overview of signal inputs / outputs is shown in Figure 1.
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INSTALLATION / MAINTENANCE INSTRUCTION
+/– 15Vdc Aux. Power (**)
FAN
FOR LAB TESTS ONLY
(**) not present in systems with P/N -XX11/-XX22
Figure 1 Interface Diagram LCR–92
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3.1.1
Parity
Parity check of Discrete Input Program Pins:
Mounting Position 1 + Mounting Position 2
+ DG-Mode Logic Select
+ Yaw Rate Select 1 + Yaw Rate Select 2
= odd
+ Turn Rate Select
+ Parity Pin
If the number of selected ( i.e. grounded or set to 28 VDC respectively ) pins is even, then the parity pin
J4-13 has to be grounded, in order to get an odd parity.
3.1.2
Azimuth Mounting Discretes
Azimuth mounting orientation in the A/C is identified by Mounting Position No.1 and No.2 Pins.
Program Pins
Plug Fwd.
Plug Aft.
Plug Rt. Wg.
Plug Lt. Wg.
Mount Pos. 1 (J4-14)
open
jump to common
open
jump to common
Mount Pos. 2 (J4-35)
open
open
Table 3
3.1.3
jump to common jump to common
Mounting Discretes
DG–Mode Logic Selection
The DG-Mode Logic Selection discrete is applied to the program pin (J4-12). This results in the
DG/MAG Mode shown under the derived input control discrete.
Program Pin J4-12
DG–Mode Logic Select
DG/MAG Mode J4-57
Input = 28 VDC
DG/MAG Mode J4-57
Input = open
open
DG-Mode
Slaved Mode
jump to common
Slaved Mode
DG-Mode
Table 4 DG-Mode Logic Selection Discretes
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INSTALLATION / MAINTENANCE INSTRUCTION
3.1.4
Source Destination Identifier
Program Pins
n/a
System No. 1
System No. 2
System No. 3
SDI 1
(J4-34)
open
jump to common
open
jump to common
SDI 2
(J4-54)
open
open
jump to common
jump to common
Table 5 Source/Destination Discretes
3.1.5
Analog Yaw Rate Scale Factor Selection
NOTE
Applicable only for AHRS equipped with a synchro card.
Program Pins
200 mV/_/s
100 mV/_/s
333 mV/_/s
666 mV/_/s
YR-Scale 1
(J4-53)
open
open
jump to common
jump to common
YR-Scale 2
(J4-11)
open
jump to common
open
jump to common
Table 6 Analog Yaw Rate Scale Factor Discretes
3.1.6
Turn Rate Select
Output of Turn Rate at ARINC label 330 instead of Yaw Rate is selected by J4-17 (referenced to J4-36*).
For calculation and bandwidth of the Turn Rate output refer to paragraph 7.3 (page 24).
Program Pin J4-17
ARINC Label 330
open
Yaw Rate
+ 28 VDC
Turn Rate
* see figure 14 (page 49).
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INSTALLATION / MAINTENANCE INSTRUCTION
3.2
Control Discretes
There are 15 AHRU connector pins allocated for control discretes as follows:
In case of multiple installations each control discrete shall be wired and controlled independently.
J4-38
MSU Calibration Discrete
+28 V = MSU Calibration Enable**
J4-55
Selftest data enable
GND = Test data enable (TTL logic)
J4-33
Maintenance data enable
GND = Maintenance data enable (TTL logic)
J4-57
DG mode select
see Table 4
J4-16
Slew Left*)
+28 V = Slew Left Platform Hdg
J4-58
Slew Right*)
+28 V = Slew Right Platform Hdg
J4–37
On ground/in air Logic
( weight on wheels )
GND = in air
Open = on ground (28 VDC logic)
J4-36
Ground Discrete Ref.
Reference for SAV input discretes
Connect to J1-15 ( see figures 13 and 14, pages
48/49)
Table 7 Control Discretes
*)
Slew function is enabled after alignment is finished.
In DG-Mode initial slew rate is 2 _/s , after 3 secs, 8 _/s.
In Slave Mode platform heading will be set to MSU heading input.
**
3.3
valid for P/N 141XXX-XX22
MSU Calibration Control Switch/Discrete
The MSU calibration control switch, located on the front of the AHRU, sets the system into the MSU
Calibration Mode. For P/N 141XXX-XX22 a SAV Control Discrete (J4-38) also sets the system into the
MSU Calibration Mode.
3.4
Digital Inputs
3.4.1
ARINC 429 Inputs
The system provides two independent ARINC 429 low speed (12.5kHz) input interfaces. The current
system mechanisation requires no ARINC 429 input. However, these interfaces are implemented for
growth potential reasons.
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INSTALLATION / MAINTENANCE INSTRUCTION
3.4.2
RS-422 Input
The system provides two independent RS-422 input interfaces. Interface 1 is used for test and calibration
purposes. Interface 2 is a spare input.
Hardware provisions are made to operate these interfaces as RS-485 bus interfaces.
Transmission Rate:
Data:
Control:
NOTE :
3.5
9600 Baud
8 Data Bits
1 Start Bit
1 Parity Bit (odd)
2 Stop Bits
The interface may be operated using the LITEF LCR-92 Level 1 Test
Set 309444.
Analog Inputs
Magnetic Heading Input
The AHRU requires a magnetic heading input direct from a flux valve.
MSU Reference Input/Output
The input MSU REF. IN (J4-60) has to be connected to MSU REF. OUT (J4-39) inside connector J4.
For P/N 124210-XXXX J4-59 has to be connected to J4-18 as well.
AC Synchro Reference Input
The AHRU requires the following 26 VRMS, 400 Hz reference signals :
PNs XXXXXX-20XX, -21XX
Attitude Reference
Heading 1 Reference
PNs XXXXXX-30XX, -31XX, and
-32XX
Attitude Reference
Heading 1 and 2 References
These signals are to be the same phase as the reference used by the connected analog indicator or control
computer.
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INSTALLATION / MAINTENANCE INSTRUCTION
4
Signal Output
The AHRU provides following power for system use :
+24 VDC
cooling fan power
+28 VDC
CCU power / discrete inputs
10.8 - 40 VRMS, 400 Hz flux valve excitation
4.1
Digital Outputs
4.1.1
ARINC 429 Outputs
The system provides three identical two-wire digital data output busses per ARINC 429, all of which
include the binary and BCD data described as follows:
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Digital Binary and Discrete Outputs
The digital binary and discrete outputs are described in the following tables:
Octal Label
Parameter
Minimum
Numbering
Update Rate Range
(Hz)
Units
Digital Binary Word Output
300**
Magnetic Sensor Input
16
"180
deg
320
Mag Heading
64
"180
deg
324
Pitch Angle
64
"180
deg
325
Roll Angle
64
"180
deg
326*
Body Pitch Rate
64
"128
deg/sec
327*
Body Roll Rate
64
"128
deg/sec
330*
Body Yaw Rate / Body Turn Rate
64
"128
deg/sec
334***
334****
Platform Heading /
Magnetic Sensor Input
64
"180
deg
302
System Time
16
65535
sec
340* 1)
Body Yaw Rate
64
"512
deg/sec
Table 8 Digital Binary Outputs
*
The system is capable of operating up to 600 deg/sec. The output is limited to "128 deg/sec, to comply with ARINC
Specification.
**
Label 300 is the filtered and compensated magnetic sensor unit heading.
***
PNs XXXXXX-XXX0. The platform heading (label 334) is identical to label 320 (mag. heading), except if the magnetic
heading reference or the magnetic sensor unit fails, then no failure is indicated on this output.
**** PNs XXXXXX-XXX1/-XXX2. Label 334 is identical to Label 300 ( Magnetic Sensor Input )
1)
P/Ns 141XXX-XX22
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Octal Label
Parameter
Minimum
Update
Rate (Hz)
Numbering Units
Range
Maintenance Discrete Word Output
350
Maintenance Discretes
16
N/A
N/A
351
Maintenance Discretes
16
N/A
N/A
352
Maintenance Discretes
16
N/A
N/A
353
Maintenance Discretes
16
N/A
N/A
354
MSU Calibration Error
16
"1.8
deg
303
Input Discrete Word 1
16
N/A
N/A
304
Input Discrete Word 2
16
N/A
N/A
Discrete Word Output
270
AHRS Discrete
16
N/A
N/A
271
AHRS Discrete
16
N/A
N/A
Table 9 Digital Binary Outputs (cont.)
Octal
Label
Parameter
Signif. Approx.
Signal
Bits
Resolution Bandwidth
(Hz)
Positive
Sense
300
Mag Sensor Input
15
.0055_
Nose Rt
320
Mag Heading
15
.0055_
Nose Rt
324
Pitch Angle
14
.01_
Nose Up
325
Roll Angle
14
.01_
R. W. Dn
326
Body Pitch Rate
13
.015_/s
8
Nose Up
327
Body Roll Rate
13
.015_/s
8
R. W. Dn
330
Body Yaw Rate
13
.015_/s
8
Nose Rt
330
Body Turn Rate* * P/N -XX00 + 0.3 Hz /
P/N -XX11 / -XX22 +0.2 Hz
13
.015_/s
0.3 / 0.2
Nose Rt
334
Platform Heading / Mag. Sensor Input
15
.0055_
302
System Time
18
1.0 s
354
MSU Cal. Error
15
.00005_
340
Body Yaw Rate (P/N -XX22)
15
.015_/s
Nose Rt
8
Nose Rt
Table 10 Digital Binary Outputs (cont.)
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INSTALLATION / MAINTENANCE INSTRUCTION
Digital BCD Outputs
The table below shows the digital BCD outputs of the AHRU.
Label (Octal)
Function
Min. Update Rate (Hz)
046
Software Version
1
377
Equipment Identification
1
Table 11 Digital BCD Outputs
4.1.2
RS-422 Output
The system provides two independent RS-422 output interfaces. Interface 1 is used for maintenance data
output and test and calibration purposes. Interface 2 is a spare output.
Hardware provisions are made to operate these interfaces as RS-485 bus interfaces.
Transmission Rate:
Data:
9600 Baud
8 Data Bits
Control:
1 Start Bit
1 Parity Bit (odd)
2 Stop Bits
NOTE :
The interface may be operated using the LITEF LCR-92 Level 1 Test
Set 309444.
NOTES : applicable to Table 12 :
*For PNs, XXXXXX-2XXX and -3XXX only.
** The autopilot heading interlock contact is open when:
–heading is invalid
–the system is switched from DG to slave mode, open for two seconds.
-slew right or left is selected, open for at least two seconds.
–MSU Calibration Mode is selected.
***
****
For PNs, 141450-XXXX and 141852-XXXX only.
For PNs, 124210-XXXX only
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INSTALLATION / MAINTENANCE INSTRUCTION
4.1.3
Discrete Flag Warn Signals
The system discrete outputs are described below ;
Parameter
Connector
Pin
Load
Capability
(mA)
Logic
Synchro Module *
J3
Attitude Warn
J3-03
J3-18
110
Contact closed = Attitude valid
Contact open = Attitude invalid
Turn Rate Warn ***
J3-02
J3-31
110
Contact closed = Turn Rate valid
Contact open = Turn Rate invalid
Yaw Rate Warn **** J3-02
J3-31
110
Contact closed = Yaw Rate valid
Contact open = Yaw Rate invalid
Heading Warn 1
J3-32
J3-17
110
Contact closed = Heading valid
Contact open = Heading invalid
Heading Warn 2
J3-16
J3-01
110
Contact closed = Heading valid
Contact open = Heading invalid
Interface Module
J4
AHRS Warn
J4-21
J4-42
110
Contact closed = AHRS valid
Contact open = AHRS invalid
DG Mode
J4-62
J4-20
110
Contact closed = DG Mode
Contact open = Slaved Mode
Yaw Rate Warn ***
J4-41
J4-61
110
Contact closed = Yaw Rate valid
Contact open = Yaw Rate invalid
Turn Rate Warn **** J4-41
J4-61
110
Contact closed = Turn Rate valid
Contact open = Turn Rate invalid
Autopilot Heading
Interlock **
110
Contact closed = Autopilot Heading valid
Contact open = Autopilot Heading invalid
J4-19
J4-40
Table 12 Discrete Flag Warn Signals
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INSTALLATION / MAINTENANCE INSTRUCTION
Figure 2 Examples of a typical wiring of a discrete output, e.g. AHRS Warn
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INSTALLATION / MAINTENANCE INSTRUCTION
4.2
Analog Outputs
4.2.1
Synchro Outputs
Notes :
1)
2)
PNs XXXXXX-20XX, -21XX
PNs XXXXXX-30XX, -31XX, -32XX
Table 13
Synchro Outputs
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4.2.2
2–Wire AC Outputs
Notes :
1)
2)
3)
**
PNs XXXXXX-20XX, -21XX
PNs XXXXXX-30XX, -31XX,
PNs XXXXXX-32XX
Positive sense in phase with reference
Table 14 2-Wire AC Outputs
4.2.3
2-Wire DC Outputs
Mag Heading Slaving Error
Defined as
Format
Scaling
Platform Heading - Magnetic Sensor Input
2-wire DC current "200 mA
"200 mA, "15 deg (full scale) into 1 kohm load
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Yaw Rate Output
PNs
XXXXXX-2XXX, -3XXX
2-wire DC "4 V full scale
100, 200, 333 or 666 mV/deg/sec depending on program pin wiring, see Table 6
or :
single DC Output, referenced to Turn Rate RTN / Yaw Rate RTN and
1/2 Scalefactor ( PNs XXXXXX-3XXX only ).
Bandwidth
output is filtered with an 8 Hz low pass filter.
Sense
Output voltage shall be positive for CW rate as viewed from above.
Range
0 – "40, "20, "12 or "6 deg/sec.
Scale Factor Accuracy"10 %
Offset
50mV
Load
1 kW
Format
Scale Factors
Turn Rate Output
PNs
XXXXXX-2XXX, -3XXX
2-Wire DC "4 V full scale
333mV/deg/sec
or :
single DC Output, referenced to Turn Rate RTN / Yaw Rate RTN and
1/2 Scalefactor ( PNs XXXXXX-3XXX only ).
Turn rate is calculated from yaw rate and roll angle:
Turn rate = yaw rate / cos ( roll angle p60° )
Bandwidth
Output is filtered with a low pass filter.
PNs XXXXXX-XXX0 : time constant 0.6s.
PNs XXXXXX-XXX1/-XX22 : time constant 0.9s.
Range
0 – "12 deg/sec
Scale Factor Accuracy"10%
Offset
50mV
Load
1 KW
Format
Scale Factor
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INSTALLATION / MAINTENANCE INSTRUCTION
4.3
Self-Test Outputs
Functional selftest can be activated when aircraft is on ground and the selftest data discrete is grounded.
These values are latched for 1 second* after the ground from J4-55 is removed. The values are listed in
the tables which follow.
* 1 minute ONLY applicable to units with the PN 124210-XX00.
Output Signal
Octal Label
Self-test Values
Discrete Words
270/271
N/A
Magnetic Sensor Input
300
N/A
Mag Heading
320
15 deg
Pitch Angle
324
+ 5 deg (Nose Up)
Roll Angle
325
+ 45 deg (Right Wing Down)
Pitch Rate Body
326
10 deg/sec (Nose Up)
Roll Rate Body
327
10 deg/sec (Right Wing Down)
Yaw Rate Body
330/340*
10 deg/sec (Nose Right)
334
22.5 deg
Platform Heading / Mag. Sensor Input
* P/N -XX22
Table 15 Digital Self-Test Outputs
Synchro Outputs
Output Signal
Self–test Value
Heading 1
Heading 2
15 deg
15 deg
Nose Right
Nose Right
Pitch
Roll
+ 5 deg
+45 deg
Nose Up
Right Wing Down
DC Voltage Outputs
Slaving Error
Yaw Rate
Turn Rate
+15 deg
+6 deg/sec
+3 deg/sec
Nose Right
Nose Right
Nose Right
Table 16 Analog Self-Test Outputs
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ATT WARN
+
Attitude invalid
HDG WARN 1
+
Heading 1 invalid
HDG WARN 2
+
Heading 2 invalid
AHRS WARN
+
AHRS valid
YAW RATE WARN
+
Yaw Rate invalid
TURN RATE WARN
+
Turn Rate invalid
DG MODE
+
DG Mode selected
AUTOPILOT HDG INTERLOCK
+
AUTOPILOT HDG invalid
Table 17 Discrete Self-Test Output
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5
Cooling Requirements
In order to improve the system reliability, the AHRU installation tray optionally incorporates an integral
cooling fan. Increased reliability will result from operation with the optional cooling fan.
6
AHRU Alignment Requirements
6.1
Installation Tray
The outline drawings of the installation trays with and without fan are shown in Figures 9, 10, 11 and 12.
The orthogonal alignment of the installation tray with respect to the pitch, roll and azimuth axis of the
aircraft is fundamental for the operation of the AHRS. Therefore, the AHRU Installation Tray, for
hard-mount as well as palletized installation, must be aligned to within $0.2 degrees to the aircraft axes.
In order to increase the alignment accuracy, the measured actual installation alignment errors can be
stored in the MSU calibration PROM. The AHRU uses the stored coefficients for misalignment
correction during operation.
NOTE :
The alignment errors can be stored using the LITEF LCR-92 Level 1 Test Set
309444.
7
Flux Valve (MSU) Calibration
7.1
General
An automatic flux valve calibration procedure is implemented in the AHRU software. The procedure
does not require supporting equipment. The procedure must be performed in a position without local
disturbances of the earth’s magnetic field as no compensation for such disturbances can be made. To
ensure that all of the factors requiring compensation are present the procedure must be performed with
the engine(s) running and all electrical systems used in flight switched on. Particular attention should be
paid to systems in the neighbourhood of the flux valve, strobe and/or position lights, pitot tube heating
etc. Prior to an initial Flux-valve installation a survey should be carried out to determine the magnetism
parameters of the location. If readings are greater than the acceptable limits the affected parts must be
degaussed, until all readings are within the limits laid down. One possible approach is to use a needle
compass and check that the magnetism readings are within the acceptable limits. When the procedure
has been completed, both single and dual cycle magnetic disturbances produced by the aircraft and its
systems are practically eliminated. A reference direction is not required. Any initial aircraft heading can
be used. If the Air/Ground discrete indicates that the aircraft is on the ground the flux valve calibration
mode may be engaged. If the Air/Ground discrete indicates that the aircraft is in the air the MSU
CAL MODE switch position is ignored and the normal mode of operation remains selected.
Note If Electrical systems, which can only be switched on in the air, must remain off, the heading
system may exhibit uncompensated errors during flight. A way should be found to switch them
on without changing the ’On Ground’ indication to AHRU.
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7.2
Index Error
When a new flux valve is installed perform a four point cardinal swing in order to eliminate the index
error.The index error of the MSU is not compensated by the automatic MSU calibration. Prior to the
procedure the MSU has to be pre-aligned manually with an accuracy of "1 degree. After the MSU
calibration the MSU may be realigned manually to eliminate the residual index error.
During the procedure the aircraft is turned clockwise to eight (initial heading, plus seven positions)
different headings about 45_ apart; a "5_ error in spacing is acceptable. These headings are indicated on
the appropriate system’s primary heading indicator.
The aircraft can be rotated about it’s vertical axis or taxied in a circle to align with the required headings.
The operator supervises the procedure via the aircraft instruments (HSI, RMI). The displayed heading
and the heading flag are used to reach the 7 headings used and to determine when the next heading
change is to be made. See the detailed procedure which follows this general description.
7.3
Calibration Procedure
The calibration mode is selected by the MSU CAL MODE switch on the front panel of the LCR-92
AHRU being placed in the up (ON) position.
As long as a heading change is less than 5_ in the calibration mode initial position the displayed heading
is the raw flux valve heading input.
When the heading change exceeds 5_ away from the position heading, the heading relative to the initial
procedure heading (0 degrees) is displayed. This means that headings do not have to be calculated by the
ground crew, the next required heading is always the next multiple of 45_ " 5° ( e.g. 45°, 90°, 135°,
180° etc.).
In each of the eight positions, including the initial position, the system accepts heading from the flux
valve. The time required for data collection depends on aircraft movements, caused for example by wind
or propeller rotation. During data collection and the turns between positions the Heading Warn Flag is
displayed. At the end of each data collection period the flag disappears, generally in less than 20 seconds,
to indicate that the turn to the next heading can be started.
If the flag does not disappear, it indicates that either the heading is outside the "5_ tolerance, or data has
not been correctly collected because of excessive aircraft motion. When this happens the procedure must
be rerun.
The Attitude Warn flag is displayed throughout the performance of the procedure.
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After data has been collected for each of the eight headings (0 to 315 degrees indication on the compass
card irrespective of the initial heading), the system calculates the compensation factors and stores this
data in the MSU calibration PROM. The MSU calibration PROM is attached to the AHRU mounting
tray. AHRU replacement does not require a new flux valve calibration.
The heading display after the compensation factors have been calculated, immediately switches to an
indication of the quality of the compensation available. The value indicated is the standard deviation of
the residual error multiplied by 100. A sucessful calibration is indicated by the retraction of the HDG
WARN flag.
If the heading warn flag continues to be displayed, the procedure failed. The indicated results are not
stored in the MSU calibration PROM and the last valid values are retained. If the heading is greater than
100_ (residual error 1_) the calibration should be regarded as invalid, even if the heading warn flag is
retracted. In this case the procedure must be re–run.
After a successful calibration, the system is returned to the normal mode of operation by placing the
AHRU switch MSU CAL MODE down to the OFF position. All warning flags disappear and normal
operation is resumed.
If the MSU CAL MODE is accidentally left in the ON position, the attitude warn flag will continue to be
displayed during ground operation. The display of these flags should prevent flight with the switch in
this position. However if the aircraft takes off despite the warning, normal operation will be resumed
when the Ground/Air discrete input indicates ’in air’. On the ground, incorrect headings will be
displayed.
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INSTALLATION / MAINTENANCE INSTRUCTION
7.4
MSU Calibration Procedure/Checklist
A/C in location with no external magnetic disturbances
engine(s) running
all electrical equipment switched on
AHRS switched on
alignment completed, all flags out of view
MSU CAL MODE switch switched to ”ON” (up)
ATT Flag in view
HDG Flag in view
Initial HDG indication: ____
HDG Flag disappears
A/C to 45_ indic. HDG
HDG Flag in view
HDG Flag disappears
A/C to 90_ indic. HDG
HDG Flag in view
HDG Flag disappears
A/C to 135_ indic. HDG
HDG Flag in view
HDG Flag disappears
A/C to 180_ indic. HDG
HDG Flag in view
HDG Flag disappears
A/C to 225_ indic. HDG
HDG Flag in view
HDG Flag disappears
A/C to 270_ indic. HDG
HDG FLag in view
HDG Flag disappears
A/C to 315_ indic. HDG
HDG Flag in view
HDG Flag disappears
Indication of calibration quality
HDG indication on compass: _____
MSU CAL MODE switch to ”OFF” (down)
HDG Flag out of view
ATT Flag out of view
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 26
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8
Outline Drawings
The outline drawing of the AHRU is shown in Fig. 3. Outline drawings of the various MSUs produced
by Bendix/King and Honeywell are shown in Figs. 4 to 6 inclusive. Likewise, the outline drawing for the
CCU is shown in Fig. 7. Figs. 8, 9, 10 and 11 show the mounting trays with or without fans fitted.
Lastly, the CalPROM is illustrated in Fig. 12.
The outline drawings are shown on the following pages (28 to 37 inclusive).
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 27
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.1
AHRU
Figure 3 AHRU Outline
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 28
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.2
MSU, Bendix/King
.49
(1.24)
1.81
(4.64)
2.375
(6.03)
3.37
(8.56)
CONNECTOR 030-2189-00
MATING CONNECTOR 030-2190-00
SUPPLIED WITH UNIT
2.38 DIA. +.020/–.000
(6.04)
089-7009-10
120°
TYP.
KMT 112
MOUNTING PLATE
.156 DIA. MOUNTING HOLES
089-8036-19(2)
089-2157-15
2.900 DIA.
(7.36)
MOUNTING HOLES LAYOUT
NOTES
1
2
3
RECOMMENDED MOUNTING
ALL DIMENSIONS IN ( ) ARE IN CENTIMETRES
WEIGHT 0.3 POUNDS (150 GRAMS)
MOUNT RIGID WITH 3 – NO. 6 NON-METALLIC SCREWS IN A REMOTE MAGNETICALLY STABLE AREA.
MOUNTING HARDWARE SUPPLIED WITH UNIT
Figure 4 KMT 112 MSU Outline and Mounting Diagram
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 29
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.3
MSU, Honeywell
Figure 5 FX-120 MSU Outline and Mounting Diagram
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 30
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.4
MSU, Honeywell
Figure 6 FX-125 / FX-220 MSU Outline and Mounting Diagram
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 31
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.5
Compass Control Unit
MATING CONNECTOR M83723-75R1415N
GEGENSTECKER M83723-75R1415N
Figure 7 CCU Outline and Mounting Diagram
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 32
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.6
Tray, without Fan
Figure 8 Tray Outline - Without Fan (P/N 124260)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 33
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.7
Tray, with Fan
Figure 9 Tray Outline - With Fan (P/N 140691)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 34
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.8
Tray without Fan
Figure 10 Tray Outline - Without Fan (P/N 124260-5000)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 35
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.9
Tray with Fan
Figure 11 Tray Outline - With Fan (P/N 140691-5000)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 36
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
8.10
CalPROM
CalPROM Module
Lettering i.a.w. MIL-STD-130 or equivalent lettering
Description. PN. SN. REV
ESD-label
Connector end housing
On delivery connector will be fitted with a dustcap
Nylon strap
Dimensions in millimetres
Figure 12 CalPROM Outline
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 37
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9
System Wiring
The following notes apply, where indicated.
NOTES
Twisted and Shielded Wires - Wires should be shielded or twisted and shielded as indicated with
an insulating jacket over the shield: The shield should be carried through each break and should
be connected at both ends external to the equipment using metal backshell / strain relief of the
respective connector, (refer to Figure 15). The Pigtail method shall be avoided.
External Program Control - Refer to Paragraph 3 for usage of external program control pins.
MSU Shield Grounding - The shielded multiple conductor cable carrying the sensitive signals
from the MSU should have its shield grounded at the backshell of the respective connector.
Figures 13 and 14 illustrate the interconnection between the CCU and LCR-92, and the interconnection
of the ground discrete reference respectively.
Figure 16 shows the Bonding Strap for the installation of AHRU with the P/N 141852-3211.
NOTE
The system wiring is laid out with particular reference to the various part numbers for the
LCR-92, i.e., J1, J2 and J5 are the same for all systems, whereas
J3 and J4 are laid out in full under the designated part number concerned.
This is for ease of use by the technician concerned.
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 38
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.1
J1 (Power Supply)
Electrical Pin Assignment J1 (Power Supply)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
+28 VDC PRIM A/C POWER
+28 VDC PRIM A/C POWER
28 VDC PRIM RETURN
28 VDC PRIM RETURN
J1-01
J1-09
J1-02
J1-10
–––––––––––––––––––
–––––––––––––––––––
–––––––––––––––––––
–––––––––––––––––––
I
I
I
I
(22)*
(22)*
(22)*
(22)*
AIRCRAFT 28 VDC
AIRCRAFT 28 VDC
DC POWER GROUND
DC POWER GROUND
2 A MAX
2 A MAX
2 A MAX
2 A MAX
+28 VDC AUX A/C Power
+28 VDC AUX A/C Power
28 VDC AUX RETURN
28 VDC AUX RETURN
J1-03
J1-11
J1-04
J1-12
–––––––––––––––––––
–––––––––––––––––––
–––––––––––––––––––
–––––––––––––––––––
I
I
I
I
(22)*
(22)*
(22)*
(22)*
AIRCRAFT 28 VDC
AIRCRAFT 28 VDC
DC POWER GROUND
DC POWER GROUND
2 A MAX
2 A MAX
2 A MAX
2 A MAX
+24 VDC SYSTEM
24 VDC SYST. RETURN
J1-13
J1-05
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
FOR LAB TEST ONLY
FOR LAB TEST ONLY
+28 VDC CCU/DISCRETES
28 VDC RTN
J1-08
J1-15
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
+28 VDC FOR CCU/INPUT DISCRETES
28VDC RETURN
SPARES
J1-06, J1-07, J1-14
* For P/N -1XXX AWG 24 may be used
9.2
J2 (Fan Supply)
Note : This connector is permanently attached to the fan wiring, therefore no installation wiring is required.
Electrical Pin Assignment J2 (Fan Supply)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
+24 VDC FAN POWER
24 VDC RETURN
J2-03
J2-02
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
FAN TEST ENABLE A
FAN TEST ENABLE B
J2-04
J2-05
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
SPARES
J2-01, J2-06 to J2-09
LOAD
100 mA MAX
100 mA MAX
JUMPER INSIDE THE
FAN CONNECTER
Table 18 System Wiring (Sheet 1 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 39
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.3
J3 (Synchro)
(only AHRU / PN 124210-2011)
Electrical Pin Assignment J3 (Synchro)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
ATTITUDE
REFERENCE
HI
LO
J3-04
J3-19
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
10 mA RMS MAX.
PITCH SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-11
J3-26
J3-40
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
ROLL SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-10
J3-25
J3-39
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
HEADING 1
REFERENCE
HI
LO
J3-05
J3-20
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
HEADING
SYNCHRO
No. 1
X(S1)
Z(S2)
Y(S3)
J3-13
J3-28
J3-42
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES HDG.1 REF)
HEADING
SYNCHRO
No. 2
X(S1)
Z(S2)
Y(S3)
J3-12
J3-27
J3-41
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
10 KW MIN.
400 Hz (USES HDG.1 REF)
PITCH AC
200mV/deg
HI
LO
J3-09
J3-24
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
200 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
ROLL AC
200mV/deg
HI
LO
J3-07
J3-22
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
200 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
PITCH AC
50mV/deg
HI
LO
J3-08
J3-23
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
ROLL AC
50mV/deg
HI
LO
J3-06
J3-21
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
YAW RATE
DC OUTPUT
HI
LO
J3-15
J3-30
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-wire DC"4V
Programmed scale see Table 6
1 KW
TURN RATE
DC OUTPUT
HI
LO
J3-14
J3-29
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-WIRE DC "4 V
0.333V/deg/sec
1 KW
ATTITUDE WARN DISCR. A
ATTITUDE WARN DISCR. B
J3-03
J3-18
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 1 A
HEADING WARN DISCR. 1 B
J3-32
J3-17
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
YAW RATE WARN DISC. A
YAW RATE WARN DISC. B
J3-02
J3-31
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 2 A
HEADING WARN DISCR. 2 B
J3-16
J3-01
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
5VRTN
J3-44
–––––––––––––––––––
O
(24)
FOR LAB TEST ONLY
SPARES
J3-43, J3-33 to 38
10 mA RMS MAX.
Table 18 System Wiring (Sheet 2 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 40
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.4
J3 (Synchro) (only AHRU / PN 141XXX-2XXX)
Electrical Pin Assignment J3 (Synchro)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
ATTITUDE
REFERENCE
HI
LO
J3-04
J3-19
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
10 mA RMS MAX.
PITCH SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-11
J3-26
J3-40
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
ROLL SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-10
J3-25
J3-39
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
HEADING 1
REFERENCE
HI
LO
J3-05
J3-20
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
HEADING
SYNCHRO
No. 1
X(S1)
Z(S2)
Y(S3)
J3-13
J3-28
J3-42
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES HDG.1 REF)
HEADING
SYNCHRO
No. 2
X(S1)
Z(S2)
Y(S3)
J3-12
J3-27
J3-41
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
10 KW MIN
400 Hz (USES HDG.1 REF)
PITCH AC
200mV/deg
HI
LO
J3-09
J3-24
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
200 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
ROLL AC
200mV/deg
HI
LO
J3-07
J3-22
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
200 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
PITCH AC
50mV/deg
HI
LO
J3-08
J3-23
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
ROLL AC
50mV/deg
HI
LO
J3-06
J3-21
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
TURN RATE
DC OUTPUT
HI
LO
J3-15
J3-30
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-wire DC"4V
0.333V/deg/sec
1 KW
YAW RATE
DC OUTPUT
HI
LO
J3-14
J3-29
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-WIRE DC "4 V
Programmed scale see Table 6
1 KW
ATTITUDE WARN DISCR. A
ATTITUDE WARN DISCR. B
J3-03
J3-18
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 1 A
HEADING WARN DISCR. 1 B
J3-32
J3-17
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
TURN RATE WARN DISC. A
TURN RATE WARN DISC. B
J3-02
J3-31
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 2 A
HEADING WARN DISCR. 2 B
J3-16
J3-01
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
5VRTN
J3-44
–––––––––––––––––––
O
(24)
FOR LAB TEST ONLY
SPARES
J3-43, J3-33 to 38
10 mA RMS MAX.
Table 18 System Wiring (Sheet 3 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 41
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.5
J3 (Synchro) (only AHRU / PN 141852-32XX)
Electrical Pin Assignment J3 (Synchro)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
ATTITUDE
REFERENCE
HI
LO
J3-04
J3-19
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
10 mA RMS MAX.
PITCH SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-11
J3-26
J3-40
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
ROLL SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-10
J3-25
J3-39
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
HEADING 1
REFERENCE
HI
LO
J3-05
J3-20
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
HEADING
SYNCHRO
No. 1
X(S1)
Z(S2)
Y(S3)
J3-13
J3-28
J3-42
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES HDG.1 REF)
HEADING 2
REFERENCE
HI
LO
J3-33
J3-34
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
HEADING
SYNCHRO
No. 2
X(S1)
Z(S2)
Y(S3)
J3-12
J3-27
J3-41
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES HDG.2 REF)
PITCH AC
167mV/deg
HI
LO
J3-09
J3-24
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
167 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
ROLL AC
167mV/deg
HI
LO
J3-07
J3-22
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
167 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
PITCH AC
50mV/deg
HI
LO
J3-08
J3-23
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
ROLL AC
50mV/deg
HI
LO
J3-06
J3-21
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
TURN RATE
DC OUTPUT
HI
LO
J3-15
J3-30
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-wire DC"4V
0.333V/deg/sec
1 KW
YAW RATE
DC OUTPUT
HI
LO
J3-14
J3-29
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-WIRE DC "4 V
Programmed scale see Table 6
1 KW
ATTITUDE WARN DISCR. A
ATTITUDE WARN DISCR. B
J3-03
J3-18
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 1 A
HEADING WARN DISCR. 1 B
J3-32
J3-17
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
YAW RATE WARN DISC. A
YAW RATE WARN DISC. B
J3-02
J3-31
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 2 A
HEADING WARN DISCR. 2 B
J3-16
J3-01
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
TURN RATE RTN
J3-43
–––––––––––––––––––
O
(24)
VIRTUAL GROUND FOR TURN RATE
YAW RATE RTN
J3-44
–––––––––––––––––––
O
(24)
VIRTUAL GROUND FOR YAW RATE
10 mA RMS MAX.
10 mA RMS MAX.
SPARE DC
OUTPUT/INPUT
HI
LO
J3-35
J3-36
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
FOR LAB TEST ONLY
SPARE
DC OUTPUT
HI
LO
J3-37
J3-38
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
FOR LAB TEST ONLY
1 KW
Table 18 System Wiring (Sheet 4 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 42
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.6
J3 (Synchro)
(only AHRU / PN 141XXX-30XX and PN 141XXX-31XX)
Electrical Pin Assignment J3 (Synchro)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
ATTITUDE
REFERENCE
HI
LO
J3-04
J3-19
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
10 mA RMS MAX.
PITCH SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-11
J3-26
J3-40
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
ROLL SYNCHRO
X(S1)
Z(S2)
Y(S3)
J3-10
J3-25
J3-39
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES ATT. REF)
HEADING 1
REFERENCE
HI
LO
J3-05
J3-20
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
HEADING
SYNCHRO
No. 1
X(S1)
Z(S2)
Y(S3)
J3-13
J3-28
J3-42
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES HDG.1 REF)
HEADING 2
REFERENCE
HI
LO
J3-33
J3-34
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
26 VRMS AC 400 Hz
FLOATING INPUT
HEADING
SYNCHRO
No. 2
X(S1)
Z(S2)
Y(S3)
J3-12
J3-27
J3-41
–––––ø––––♦––––––––
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
O
(24)
(24)
(24)
3-WIRE SYNCHRO OUTPUT
11.8 VRMS LEG TO LEG
3 x (120 + j450)W
400 Hz (USES HDG.2 REF)
PITCH AC
200mV/deg
HI
LO
J3-09
J3-24
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
200 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
ROLL AC
200mV/deg
HI
LO
J3-07
J3-22
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
200 mV/deg VRMS
400 Hz FLOATING OUTPUT
5 KW MIN
PITCH AC
50mV/deg
HI
LO
J3-08
J3-23
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
ROLL AC
50mV/deg
HI
LO
J3-06
J3-21
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
50 mV/deg VRMS
400 Hz FLOATING OUTPUT
10 KW MIN
TURN RATE
DC OUTPUT
HI
LO
J3-15
J3-30
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-wire DC"4V
0.333V/deg/sec
1 KW
YAW RATE
DC OUTPUT
HI
LO
J3-14
J3-29
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
2-WIRE DC "4 V
Programmed scale see Table 6
1 KW
ATTITUDE WARN DISCR. A
ATTITUDE WARN DISCR. B
J3-03
J3-18
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 1 A
HEADING WARN DISCR. 1 B
J3-32
J3-17
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
YAW RATE WARN DISC. A
YAW RATE WARN DISC. B
J3-02
J3-31
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
HEADING WARN DISCR. 2 A
HEADING WARN DISCR. 2 B
J3-16
J3-01
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
TURN RATE RTN
J3-43
–––––––––––––––––––
O
(24)
VIRTUAL GROUND FOR TURN RATE
YAW RATE RTN
J3-44
–––––––––––––––––––
O
(24)
VIRTUAL GROUND FOR YAW RATE
10 mA RMS MAX.
10 mA RMS MAX.
SPARE DC
OUTPUT/INPUT
HI
LO
J3-35
J3-36
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
FOR LAB TEST ONLY
SPARE
DC OUTPUT
HI
LO
J3-37
J3-38
–––––ø––––♦––––––––
–––––ø––––♦––––––––
O
O
(24)
(24)
FOR LAB TEST ONLY
1 KW
Table 18 System Wiring (Sheet 5 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 43
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.7
J4 (I/O)
(only AHRU / PN 124210-XXXX)
Electrical Pin Assignment J4 (I/O)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
MSU
SIGNAL
INPUT
GND
J4-51
J4-09
J4-30
J4-50
––––––ø––––♦–––––––
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
I
O
(24)
(24)
(24)
(24)
ANALOG SIGNAL ( see Table 19 )
ANALOG SIGNAL ( see Table 19 )
ANALOG SIGNAL ( see Table 19)
FOR LAB TEST ONLY
MSU REFERENCE
GND
OUT
GND
J4-39
J4-59
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
CONNECT TO J4-60
CONNECT TO J4-18
MSU REFERENCE
GND
IN
GND
J4-60
J4-18
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
CONNECT TO J4-39
CONNECT TO J4-59
FLUX VALVE
EXCITATION
HI
LO
J4-02
J4-22
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
7.2 - 40VRMS
400Hz (depends on MSU type)
SLAVING ERROR
HI
LO
J4-10
J4-31
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
2-WIRE DC CURRENT
"200 mA/"15_ FULL SCALE 1 KW
RS 422 TXD1
HI
LO
J4-04
J4-25
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
RS 422 RXD1
HI
LO
J4-26
J4-46
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
RS 422 TXD2
HI
LO
J4-24
J4-44
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
RS 422 RXD2
HI
LO
J4-45
J4-03
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
PROG. PIN COMMON
J4-32
–––––––––––––––––––
O
(24)
SIGNAL GROUND
MTG. POS #1
MTG. POS #2
J4-14
J4-35
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
ORIENTATION DISCRETE
ORIENTATION DISCRETE
J4-34
J4-54
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
J4-13
–––––––––––––––––––
I
(24)
SELFTEST DATA ENABLE
J4-55
–––––––––––––––––––
I
(24)
GND = SELFTEST DATA SELECTED
MAINTENANCE DATA
J4-33
–––––––––––––––––––
I
(24)
GND = MAINTENANCE DATA ENABLE
DG MODE LOGIC SELECT
J4-12
–––––––––––––––––––
I
(24)
GND or OPEN ( SEE TABLE 4 )
YAW RATE SF NO.1
YAW RATE SF NO.2
J4-53
J4-11
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
SCALE FACTOR OF THE ANALOG YAW
RATE OUTPUT
DG / MAG MODE SELECT
J4-57
–––––ø––––♦––––––––
I
(24)
+28 VDC or GND (SEE TABLE 4 )
SLEW LEFT
SLEW RIGHT
J4-16
J4-58
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
+28 VDC = HEADING SLEW LEFT
+28 VDC = HEADING SLEW RIGHT
ON GND/IN AIR DISCRETE
J4-37
–––––––––––––––––––
I
(24)
GND = AIRCRAFT AIRBORNE
OPEN = AIRCRAFT ON GROUND
TURN RATE SELECT
J4-17
–––––––––––––––––––
I
(24)
+28VDC = TURN RATE SELECTED ON ARINC
LABEL 330
SPARE DISCRETE
J4-38
–––––––––––––––––––
I
(24)
28 VDC LOGIC
GROUND DISCRETE REF.
J4-36
–––––––––––––––––––
I
(24)
REFERENCE FOR SAV ( Standard Applied
Voltage ) INPUT DISCRETES
SOURCE DESTINATION
IDENTIFIER
PARITY DISCRETE
No.1
No.2
Table 18 System Wiring (Sheet 6 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 44
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
DG MODE ANNUNCIATOR A
DG MODE ANNUNCIATOR B
J4-62
J4-20
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = DG MODE SEL.
110 mA
AHRS WARN DISCRETE
AHRS WARN DISCRETE
A
B
J4-21
J4-42
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = AHRS VALID
110 mA
TURN RATE WARN DISC. A
TURN RATE WARN DISC. B
J4-41
J4-61
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
AUTOP. HDG INTERLOCK A
AUTOP. HDG INTERLOCK B
J4-19
J4-40
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
ARINC 429 OUTP.
DATA BUS No.1
A
B
J4-08
J4-29
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
ARINC 429
HIGH SPEED 100 KHz
40 mA DC
ARINC 429 OUTP.
DATA BUS No.2
A
B
J4-49
J4-07
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
ARINC 429
HIGH SPEED 100 KHz
40 mA DC
ARINC 429 OUTP.
DATA BUS No.3
A
B
J4-28
J4-48
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
ARINC 429
HIGH SPEED 100 KHz
40 mA DC
ARINC 429 INP.
DATA BUS No.1
A
B
J4-06
J4-27
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
ARINC 429
LOW SPEED 12.5 KHz
3 KW MIN
ARINC 429 INP.
DATA BUS No.2
A
B
J4-47
J4-05
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
ARINC 429
LOW SPEED 12.5 KHz
3 KW MIN
15 V RTN
+ 15 V
J4-56
J4-52
––––––––––––––––––––
––––––––––––––––––––
O
O
(24)
(24)
FOR LAB TEST ONLY
FOR LAB TEST ONLY
SPARES
J4-01 ,J4-15 ,J4-23 ,J4-43
9.8
J4 (I/O)
(only AHRU / PN 141450-XXXX and 141852-XXXX)
Electrical Pin AssignmentJ4 (I/O)
FUNCTION
CONNECTOR PIN
MSU
SIGNAL
INPUT
GND
J4-51
J4-09
J4-30
J4-50
––––––ø––––♦–––––––
––––––ø––––♦–––––––
––––––ø––––♦–––––––
IN/OUT
I
I
I
O
AWG SIGNAL FORMAT
(24)
(24)
(24)
(24)
ANALOG SIGNAL (see Table 19)
ANALOG SIGNAL (see Table 19)
ANALOG SIGNAL (see Table 19)
FOR LAB TEST ONLY
LOAD
MSU REFERENCE
GND
OUT
J4-39
J4-59
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
CONNECT TO J4-60
FOR LAB TEST ONLY
MSU REFERENCE
GND
IN
J4-60
J4-18
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
CONNECT TO J4-39
FOR LAB TEST ONLY
FLUX VALVE
EXCITATION
HI
LO
J4-02
J4-22
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
7.2 - 40VRMS
400Hz (depends on MSU type)
SLAVING ERROR
HI
LO
J4-10
J4-31
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
2-WIRE DC CURRENT
"200 mA/"15_ FULL SCALE 1 KW
RS 422 TXD1
HI
LO
J4-04
J4-25
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
RS 422 RXD1
HI
LO
J4-26
J4-46
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
RS 422 TXD2
HI
LO
J4-24
J4-44
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
Table 18 System Wiring (Sheet 7 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 45
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
RS 422 RXD2
J4-45
J4-03
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
PROG. PIN COMMON
J4-32
–––––––––––––––––––
O
(24)
SIGNAL GROUND
MTG. POS #1
MTG. POS #2
J4-14
J4-35
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
ORIENTATION DISCRETE
ORIENTATION DISCRETE
J4-34
J4-54
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
PARITY DISCRETE
J4-13
–––––––––––––––––––
I
(24)
SELFTEST DATA ENABLE
J4-55
–––––––––––––––––––
I
(24)
GND = SELFTEST DATA SELECTED
MAINTENANCE DATA
J4-33
–––––––––––––––––––
I
(24)
GND = MAINTENANCE DATA ENABLE
DG MODE LOGIC SELECT
J4-12
–––––––––––––––––––
I
(24)
GND or OPEN ( SEE TABLE 4 )
YAW RATE SF NO.1
YAW RATE SF NO.2
J4-53
J4-11
–––––––––––––––––––
–––––––––––––––––––
I
I
(24)
(24)
SCALE FACTOR OF THE ANALOG YAW
RATE OUTPUT
DG / MAG MODE SELECT
J4-57
–––––ø––––♦––––––––
I
(24)
+28 VDC or GND (SEE TABLE 4 )
SLEW LEFT
SLEW RIGHT
J4-16
J4-58
–––––ø––––♦––––––––
–––––ø––––♦––––––––
I
I
(24)
(24)
+28 VDC = HEADING SLEW LEFT
+28 VDC = HEADING SLEW RIGHT
ON GND/IN AIR DISCRETE
J4-37
–––––––––––––––––––
I
(24)
GND = AIRCRAFT AIRBORNE
OPEN = AIRCRAFT ON GROUND
TURN RATE SELECT
J4-17
–––––––––––––––––––
I
(24)
+28VDC = TURN RATE SELECTED ON ARINC
LABEL 330
MSU CALIBRATION DISCRETE
J4-38
–––––––––––––––––––
I
(24)
+28VDC = MSU CALIBRATION ENABLE*
GROUND DISCRETE REF.
J4-36
–––––––––––––––––––
I
(24)
REFERENCE FOR SAV ( Standard Applied
Voltage ) INPUT DISCRETES
DG MODE ANNUNCIATOR A
DG MODE ANNUNCIATOR B
J4-62
J4-20
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = DG MODE SEL.
110 mA
AHRS WARN DISCRETE
AHRS WARN DISCRETE
A
B
J4-21
J4-42
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = AHRS VALID
110 mA
YAW RATE WARN DISC.
YAW RATE WARN DISC.
A
B
J4-41
J4-61
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
AUTOP. HDG INTERLOCK A
AUTOP. HDG INTERLOCK B
J4-19
J4-40
–––––––––––––––––––
–––––––––––––––––––
O
O
(24)
(24)
RELAY CONTACT
CLOSED = VALID
110 mA
ARINC 429 OUTP.
DATA BUS No.1
A
B
J4-08
J4-29
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
ARINC 429
HIGH SPEED 100 KHz
40 mA DC
ARINC 429 OUTP.
DATA BUS No.2
A
B
J4-49
J4-07
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
ARINC 429
HIGH SPEED 100 KHz
40 mA DC
ARINC 429 OUTP.
DATA BUS No.3
A
B
J4-28
J4-48
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
ARINC 429
HIGH SPEED 100 KHz
40 mA DC
ARINC 429 INP.
DATA BUS No.1
A
B
J4-06
J4-27
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
ARINC 429
LOW SPEED 12.5 KHz
3 KW MIN
ARINC 429 INP.
DATA BUS No.2
A
B
J4-47
J4-05
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
ARINC 429
LOW SPEED 12.5 KHz
3 KW MIN
15 V RTN
+ 15 V
J4-56
J4-52
––––––––––––––––––––
––––––––––––––––––––
O
O
(24)
(24)
FOR LAB TEST ONLY
FOR LAB TEST ONLY
SPARES
J4-01, J4-15, J4-23, J4-43
SOURCE DESTINATION
IDENTIFIER
HI
LO
No.1
No.2
* P/N 141XXX-XX22 only, all other P/N “spare discrete”.
Table 18 System Wiring (Sheet 8 of 9)
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 46
November1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
9.9
J5 (MSU CalPROM)
NOTE : No wiring is required for the MSU CalProm upon installation.
Electrical Pin AssignmentJ5 (MSU CalPROM)
FUNCTION
CONNECTOR PIN
IN/OUT
AWG SIGNAL FORMAT
LOAD
+5 VDC CalPROM POWER
5 VDC RETURN
J5-01
J5-02
–––––––––––––––––––
–––––––––––––––––––
O
I
(24)
(24)
AHRU +5 VDC
DC POWER GROUND
SPROMCS
STXCLK
STXD
SRXD
J5-06
J5-05
J5-03
J5–04
–––––––––––––––––––
–––––––––––––––––––
–––––––––––––––––––
–––––––––––––––––––
O
O
O
I
(24)
(24)
(24)
(24)
TTL
TTL
TTL
TTL
RS-422 TXD1
HI
LO
J5-14
J5-15
––––––ø––––♦–––––––
––––––ø––––♦–––––––
O
O
(24)
(24)
FOR LAB TEST ONLY
RS-422 RXD1
HI
LO
J5-12
J5-13
––––––ø––––♦–––––––
––––––ø––––♦–––––––
I
I
(24)
(24)
FOR LAB TEST ONLY
PROGRAM LOAD ENABLE*
J5–07
–––––––––––––––––––
I
(24)
FOR LAB TEST ONLY
CAL.PROG. LOAD DISCR.*
J5-08
–––––––––––––––––––
I
(24)
FOR LAB TEST ONLY
HIL TEST ENABLE*
J5-09
–––––––––––––––––––
I
(24)
FOR LAB TEST ONLY
TIME TAG C. RESET
J5-10
–––––––––––––––––––
I
(24)
FOR LAB TEST ONLY
SPARE
J5-11
––––♦–––– twisted wire
––––♦––––
––ø–♦–––– twisted and shielded wire
––ø–♦––––
Table 18 System Wiring (Sheet 9 of 9)
AHRU Input
Connector Pin
Bendix./King
KMT 112
Honeywell
FX-120
Honeywell
FX-125
Honeywell
FX-220
J4–51
A
B
B
B
J4–09
D
A
A
A
J4–30
B
C
C
C
J4–02
H
D
D
D
J4–22
E
E
E
E
F
F
F
not con.
Table 19 AHRU/MSU Wiring
LITEF DOCUMENT No: 141450–0000–840
SECTION 1 Page 47
November 1998
GmbH
INSTALLATION / MAINTENANCE INSTRUCTION
GND DISCRETE REF
*
28
+28 VDC
J1-15
J1-08
* not necessary for P/N -XX11 / -XX22
Figure 13 Interconnection Diagram CCU, LCR-92
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*
* not necessary for P/N -XX11 / -XX22
Figure 14 Interconnection Diagram Ground Discrete Reference
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Figure 15 Shield termination of connectors using Metal Backshell/Strain Relief method
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Figure 16 Bonding Strap for the installation of AHRU P/N 141852-3211
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SECTION 2
DESCRIPTION AND OPERATION
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1
General
This section provides on-aircraft maintenance procedures for the LCR-92 Attitude and Heading
Reference System (AHRS). A system consists of an Attitude and Heading Reference Unit (AHRU), a
Magnetic Sensor Unit (MSU) and, optionally, a compass controller unit (CCU).
Section 1, Installation Instructions, contains information that can be pertinent to on-aircraft maintenance
of the AHRS; that information should be used in conjunction with this section when applicable.
2
Purpose of Equipment
The LCR-92 Attitude and Heading Reference System (AHRS) is an all attitude inertial sensor system
which provides aircraft attitude, heading and flight dynamics information to display, flight control,
weather radar antenna platform and other aircraft systems and instruments.
3
Leading Particulars
Leading particulars for the AHRS are provided in Section 1, Paragraph 1, Installation Data.
4
Description
Descriptive information pertaining to the AHRS units is provided in the following Paragraphs:
4.1
Location of Units in Aircraft.
Provided in Section 1, Paragraph 1.2, Installation Data.
4.2
Outline and Mounting Drawings
Outline and mounting drawings for the AHRU, MSU, CCU, AHRU trays and CalPROM are provided in
Figures 3 through 12 of section 1.
4.3
AHRU
The LCR-92 is mechanized as a strapdown inertial measurement system using fiber optic rate gyros
which are ”strapped down” to the aircraft axes. A digital computer mathematically integrates the rate
data to obtain heading, pitch and roll. A flux valve (MSU) and one dual axis level sensor provide long
term references for the system.
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4.4
MSU
The magnetic sensor unit detects the horizontal component of the earth’s magnetic field and transmits it
to the AHRU for use as long term correction information.
4.5
CCU (Optional)
The CCU contains controls and annunciators to facilitate manual slaving of the AHRU to the MSU and
provides the following additional capabilities to the AHRS:
–
Slaved or free gyro (DG) operation mode selection..
–
Setting of compass heading during free gyro (DG) mode operation.
–
Fast slaving during operation at extreme latitudes.
–
Nulling of compass error after alignment in areas of high magnetic disturbances.
The CCU allows crew selection of either DG or slaved magnetic modes. A slaving error annunciator and
slew switch are provided for setting the compass heading in DG mode and to provide an indication of
synchronization in slaved magnetic mode. The slew switch may also be used to manually correct
heading information during operation in extreme latitudes.
5
Modes of Operation
The AHRS provides the following modes of operation:
*
Alignment (On ground or in air)
*
Normal Mode –
–
Slave Mode (Valid MSU data)
DG Mode (MSU data not valid or manually selected DG Mode)
*
MSU Calibration Mode
*
Maintenance Mode
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5.1
Alignment
5.1.1
General
Following initial power application, the system performs an alignment sequence which consists of two
alignment phases. During the alignment sequence, the attitude and heading warn discretes are set to warn
condition and bits 15 and 11 are set in Label 270 of the DITS (Digital Information Transfer System)
output, together with no computed data (NCD) in Label 320 to 325.
After short power interrupts (duration less than 500 ms) the AHRS provides a short initialization
sequence which results in valid attitude, heading and rate data after less than 45 ms. Power interrupts
longer than 500 ms will result in an IN AIR Alignment
5.1.2
Alignment Phase 1
The minimum duration of alignment phase 1 is 15 seconds whether the aircraft is on ground or in air. If
the system ambient temperature is outside the range of +15_C to +35_C, the duration may increase up to
30 seconds.
During alignment phase 1, the analog outputs are set to zero, thereafter the actual computed values are
output on the synchro and AC outputs of pitch, roll and heading. However, the discrete valids are set to
valid only after the successful completion of the alignment phase 2.
The DITS outputs of pitch, roll and yaw rate as well as the analog output of yaw and turn rates are valid
after completion of alignment phase 1.
5.1.3
Alignment Phase 2
For static conditions this mode lasts 15 seconds (after phase 1). Static conditions are defined as follows:
On Ground Alignment
The aircraft has to be stationary for the first 30 seconds after power-on. However, wind buffeting, cargo
loading etc. does not affect the alignment duration.
In order to lower the heading drift in DG-Mode, the earth rate and gyro drift are estimated during and
after alignment. The maximum estimation time is 120 seconds, if no excessive motion has been detected.
The estimated value is stored after 120 seconds and the AHRU takes this value for initialization of the
next estimation..
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In Air Alignment
The aircraft has to be flying under straight and level flight conditions for the alignment period. Under
normal flight conditions with moderate turbulance alignment will not take longer than 2 minutes.
When excessive motion is detected the AHRS is switched automatically to the moving alignment
sequence. In this sequence the completion of attitude and heading alignment depends on internal
calculated parameters, which indicate a sufficient alignment accuracy. After both have been set valid
alignment phase 2 is completed.
After successful completion of alignment phase 2 all output data are set valid and the accuracies
specified are applicable.
5.2
Normal Mode
5.2.1
Slave Mode
In Slave Mode the system heading loop is supplied with valid MSU data.
5.2.2
DG Mode
The Directional Gyro Mode can be activated manually by the DG Mode Select discrete.
5.3
MSU Calibration Mode
The MSU calibration mode is manually selected by the MSU calibration control switch. In MSU
calibration mode the system determines the MSU calibration coefficients. After successful calibration
the coefficients will be stored in the MSU Calibration PROM. Details are given in Section 1, Paragraph
7.
5.4
Maintenance Mode
5.4.1
General
The Maintenance Mode is manually selected by the maintenance control discrete, which has to be set
before power–on.
The only output of the system in the maintenance mode is the failure history and the elapsed time
recorded by the elapsed time counter implemented in the software.
The maintenance mode is enabled, if the aircraft is determined to be on the ground by the GND/Air
Control Discrete.
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5.4.2
Failure Logging and Malfunction Storage
The AHRS provides the capability for recording failure data. This is achieved by storing failure
maintenance data in labels 350, 351, 352 and 353 in the EEPROM.
The EEPROM area is subdivided into records, each record consisting of the labels 350, 351, 352 and
353. The System will initialize the EEPROM at turn-on to determine which record should be used for the
current power-on phase (logic has been implemented to differentiate between a short power interrupt
and a new turn-on to determine if re-initialization is necessary).
The System also periodically monitors the state of maintenance words to see if any new failure has
occured. All data are latched in the EEPROM (if an intermittent failure disappears, the record of its
occurence will not be removed).
After a successful completion of a repair the stored failure data in the EEPROM can be erased by special
test equipment.
The failure memory is capable of storing up to 192 failure records. The oldest failure records will be
overwritten, if more than 192 failure records are recorded.
5.4.3
Output of the Failure History and Elapsed Time
If the system is in Maintenance Mode (maintenance data discrete is set) the failure history and elapsed
time will be provided via the RS-422 output interface 1. The elapsed time counter has a range in excess of
100,000 hours.
PNs 141XXX-XX22 provide the maintenance data on the ARINC 429 bus also.
NOTE:
P/N 124210-XX00 does not provide the elapsed time information.
The data are transmitted cyclicly starting with the accumulated operating hours followed by the most
recent failure record. After all records have been transmitted the program waits for one second before
repeating the output.
The following table defines the transmission frame of the output. The LSB of the elapsed time readout is
equal to 0.1h. The significant 16 bits of each maintenance word will be transmitted only. The checksum
is the ones complement of the word wise accumulation of the preceding 4 words (respectively 2 words
for the elapsed time) and the record number.
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1.
Record
Upper Byte of Record Number “0”
Lower Byte of Record Number “0”
Bit 32-Bit 25 of elapsed time
Bit 24-Bit 17 of elapsed time
Bit 16-Bit 09 of elapsed time
Bit 08-Bit 01 of elapsed time
Upper Byte of Checksum
Lower Byte of Checksum
2.
Record
Upper Byte of Record Number “n”
Lower Byte of Record Number “n”
Bit 29-Bit 22 of Label 350
Bit 21-Bit 14 of Label 350
Bit 29-Bit 22 of Label 351
Bit 21-Bit 14 of Label 351
Bit 29-Bit 22 of Label 352
Bit 21-Bit 14 of Label 352
Bit 29-Bit 22 of Label 353
Bit 21-Bit 14 of Label 353
Bit 32-Bit 25 of elapsed time @ failure condition*
Bit 24-Bit 17 of elapsed time @ failure condition*
Bit 16-Bit 09 of elapsed time @ failure condition*
Bit 08-Bit 01 of elapsed time @ failure condition*
Upper Byte of Checksum
Lower Byte of Checksum
*
the time tag in case of a Bite entry into memory is utilised in P/N
141XXX-XX22
Table 1 Failure Transmission Frame (Sheet 1 of 2)
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3.
Record
Upper Byte of Record Number “n–1”
Lower Byte of Record Number “n–1”
Bit 29-Bit 22 of Label 350
Bit 21-Bit 14 of Label 350
Bit 29-Bit 22 of Label 351
Bit 21-Bit 14 of Label 351
S
S
4.
Record
Upper Byte of Record Number “max (1, n–191)”
Lower Byte of Record Number “max (1, n–191)”
Bit 29-Bit 22 of Label 350
Bit 21-Bit 14 of Label 350
Bit 29-Bit 22 of Label 351
Bit 21-Bit 14 of Label 351
Bit 29-Bit 22 of Label 352
Bit 21-Bit 14 of Label 352
Bit 29-Bit 22 of Label 353
Bit 21-Bit 14 of Label 353
Bit 32-Bit 25 of elapsed time @ failure condition*
Bit 24-Bit 17 of elapsed time @ failure condition*
Bit 16-Bit 09 of elapsed time @ failure condition*
Bit 08-Bit 01 of elapsed time @ failure condition*
Upper Byte of Checksum
Lower Byte of Checksum
*
the time tag in case of a Bite entry into memory is utilised in P/N
141XXX-XX22
m+2..........193
n+1..........2^16–1
Table 1 Failure Transmission Frame (Sheet 2 of 2)
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6
Power Interruptions
6.1
General
During power interruptions (less than 13.5 VDC), the system switches off immediately (< 20ms). Once
the power returns the system automatically switches on, and depending on various criteria, there are two
system responses. Initialization is performed after a short power interrupt, which is designed to restore
the system to valid operation 45 milliseconds after the input voltage is greater than the 18 VDC
threshold. For a long power interrupt a complete realignment is initiated.
6.2
Short Power Interrupt
Duration:
less than or equal to 445 milliseconds.
System response:
Fast initialization giving valid operation within 45 msec of power reaching the 18
VDC threshold. For example, after a power interrupt of 50 msec in duration, the
AHRS will output valid ARINC 429 data, synchro outputs and flags 95 msec after
the start of power interrupt. The SSM after the interrupt is the same as before the
interrupt unless the system status changed during the interrupt.
6.3
Long Power Interrupt
Duration:
more than 600 milliseconds.
System response:
Normal turn-on sequence initiated with complete realignment as per paragraph
5.1. Interrupt duration between 445 and 600 msec may result in the first or second
response due to hardware component tolerances.
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SECTION 3
TESTING AND TROUBLESHOOTING
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1
General
A typical AHRS installation is shown in the block diagram of Figure 1 of Section 3. Depending on the
aircraft avionics system configuration one or two AHRUs may be installed.
No manual testing of the AHRS is required, and troubleshooting is simplified by the built-in fault
monitoring and self-test circuits of the AHRU. When power is applied to the system, a series of self-tests
are performed to verify system functions. In addition, the system contains hardware and software
monitors and performs continuous background hardware and software verification tests. Failure of these
tests results in output of warn signals or system shutdown. The Maintenance Discrete Output words are
shown in Tables 1 through 4. Heading Fail, Attitude Fail, Yaw Rate Fail and Turn Rate Fail warning
signals will set flags on the aircraft flight displays. The AHRS Fail warning signal provides a fail
warning output any time one of the basic display warnings is set. This AHRS Fail warning can be used in
conjunction with the MASTER WARNING display system.
Manually initiated self-tests can also be performed on each of the individual AHRUs. Self-test discretes,
one for each of the AHRUs, are provided for implementation. Actuation of the discrete causes that unit to
output test values to the aircraft systems. The parameters output and the associated test values are shown
in Section 1, Paragraph 4.3. A chart of fault monitoring provisions is included in Tables 1 through 4 of
Section 3.
The fault history of the AHRU may be accessed by using LITEF LCR-92 Level 1 Test Set 309444, or any
other commercially available data download equipment. More details are laid out in paragraph 4 of this
section.
NOTE
Paragraph 3 shows the check-list for the steps to be followed, when a fault appears during
an initial installation of a system. Likewise, the check-list may also be consulted as a fault
finding guide during the time that the equipment is in service.
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E
FLIGHT
MANAGEMENT
SYSTEM
E
FLIGHT
DATA
RECORDER
Figure 1 Typical LCR-92 AHRS Installation
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2
Maintenance Discrete Outputs
DITS labels 350 - 353 contain discrete information to assist in fault finding. This information represents
the actual failure status of the system and will be provided during normal operation.
The following tables define the allocation of these bits.
MAINTENANCE DISCRETE WORD 1, Label 350
BIT No.
FUNCTION
POSSIBLE CAUSE
ACTION
1 - 13
not applicable
14
NOTE
RAM fail
AHRU defective
return AHRU for repair
15
EEPROM fail
AHRU defective
return AHRU for repair
16
MSU CalPROM fail
CalPROM not installed
CalPROM defective
AHRU defective
check installation, check
CalPROM connectors.
replace CalPROM
return AHRU for repair
17
Program cycle fail
AHRU defective
return AHRU for repair
18
Scheduler fail
AHRU defective
return AHRU for repair
19
Real Time Interrupt fail
AHRU defective
return AHRU for repair
20
Watch Dog Timer fail
AHRU defective
return AHRU for repair
21
Power Interrupt Timer fail
AHRU defective
return AHRU for repair
22
Misalignment CalPROM fail
CalPROM not installed
CalPROM defective
CalPROM incorrectly
programmed
AHRU defective
check installation,
replace and/or reprogram,
reprogram
AHRU defective
return AHRU for repair
AHRU defective
return AHRU for repair
insufficient or excessive
current to Fan
check wiring, and supply to
Fan, check power consumption,
check voltage between pin J2-3
and J2-2 for 24V/50mA.
check wiring and/or connector
pins
return AHRU for repair
23
Processor Test fail
24
not applicable
25
EEPROM Access fail
26
not applicable
27
Fan Supply Monitor
28 - 29
not applicable
30 - 31
SSM (always 0)
32
Odd Parity
1
1
(after
replacement)
return AHRU for repair
Table 1 Maintenance Discrete Outputs (Label 350)
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MAINTENANCE DISCRETE WORD 2, Label 351
BIT No.
FUNCTION
POSSIBLE CAUSE
ACTION
1 - 13
not applicable
14
NOTE
FOG auxiliary control loop fail 1
AHRU defective
return AHRU for repair
15
FOG auxiliary control loop fail 2
AHRU defective
return AHRU for repair
16
FOG Signal Noise Test
AHRU defective
return AHRU for repair
17
Max. Angular Rate exceeded
Excessive rates during
flight
AHRU defective
check flight profile
return AHRU for repair
18
Temp. Sensor fail
AHRU defective
return AHRU for repair
19
Sensor max. temp. exceeded
Excessive temperatures
during operation
AHRU defective
check ambient temperatures
Excessive vibration
check fixture/AHRU/tray (eg.
screws insecure)
return AHRU for repair
20
Level Sensor fail
AHRU defective
21
Attitude Plausibility Test
return AHRU for repair
Excessive dynamics for
extended periods,
Excessive drift
check flight profile
return AHRU for repair
22
Sensor MUX/ADC fail
(instrument failure)
AHRU defective
return AHRU for repair
23
MSU Data fail
MSU not installed,
no MSU data in/out,
check installation
check wiring/connectors
check flux-valve
return AHRU for repair
AHRU defective
24 - 29
not applicable
30 - 31
SSM (Always 0)
32
Odd parity
Table 2 Maintenance Discrete Outputs (Label 351)
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MAINTENANCE DISCRETE WORD 3, Label 352
BIT No.
FUNCTION
POSSIBLE CAUSE
ACTION
1 - 13
not applicable
14
DITS self-test fail
AHRU defective
return AHRU for repair
15
DITS transmitter not ready
AHRU defective
return AHRU for repair
16
DITS wrap-around fail
AHRU defective
return AHRU for repair
17
Analogue/Digital Converter
fail (I/O)
AHRU defective
return AHRU for repair
18
Slaving error DAC reference
fail
AHRU defective
return AHRU for repair
19
Discrete output fail (I/O)
AHRU defective
return AHRU for repair
20
MSU reference not available
no input signal at J4-60
available
AHRU defective
check availability of jumper
J4-39 to J4-60,
check signal at J4-60 for 800
Hz and 2.5Vrms,
return AHRU for repair
Incorrect or broken
wiring
Parity not odd,
AHRU defective
rectify i. a. w. Section 1,
paragraph 3.1.1.
check Parity status
return AHRU for repair
Flux-valve not calibrated
Flux-valve defective
Flux-valve installation
faulty
calibrate flux-valve,
AHRU defective
return AHRU for repair
21
Program Pin Monitor
22
not applicable
23
Heading Plausibility Test fail
24 - 29
not applicable
30 - 31
SSM (always 0)
32
Odd parity
NOTE
replace flux-valve
check installation
Table 3 Maintenance Discrete Outputs (Label 352)
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MAINTENANCE DISCRETE WORD 4, Label 353
BIT No.
FUNCTION
POSSIBLE CAUSE
ACTION
NOTE
1 - 13
not applicable
14
Attitude reference unavailable
no external input
check wiring to/from 400 Hz
source and AHRU
3
15
Heading reference 1 unavailable
no external input
(broken wire(s))
AHRU defective
check wiring to/from 400 Hz
source and AHRU
return AHRU for repair
3
16
Heading Synchro 1 fail
AHRU defective
return AHRU for repair
17
Roll Synchro fail
short circuit in wiring,
AHRU defective
check wiring to/from synchros.
return AHRU for repair
18
Pitch Synchro fail
short circuit in wiring,
AHRU defective
check wiring to/from synchros.
return AHRU for repair
19
Yaw Rate DC output fail
short circuit in wiring,
AHRU defective
check wiring to/from synchros.
return AHRU for repair
20
Turn Rate DC output fail
short circuit in wiring,
AHRU defective
check wiring to/from synchros.
return AHRU for repair
21
Discrete output fail
AHRU defective
return AHRU for repair
22
Heading Synchro 2 fail
AHRU defective
return AHRU for repair
2
23
Heading reference 2 unavailable
no external input,
(broken wire(s)),
AHRU defective
check wiring to/from 400 Hz
source and AHRU.
return AHRU for repair
3
24 - 29
not applicable
30 - 31
SSM (Always 0)
32
Odd parity
Table 4
Maintenance Discrete Outputs (Label 353)
NOTE
1)
Recalibrate AHRU/CalPROM, if CalPROM was replaced
2)
applicable for PN XXXXXX-3XXX only
3)
not stored into the malfunction memory
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3
Initial Installation of an AHRU Fault Finding Check-list
During the first integration testing of an AHRU, or a fault symptom shows during subsequent tests, the
fault should be analysed in accordance with the following check-list. Note that some of the steps state
that an EFIS is part of the system, but it could well be that an operator has another form of
instrument display panel, eg. HSI / EHSI, etc. Therefore this must be taken into consideration
when working through the steps.
AHRS EQUIPPED WITHOUT A SYNCHRO CARD
3.1
STEP 1 : EFIS DOES NOT DISPLAY ANY DATA
POWER
Check pins J1- 01/09 (28VDC) and J1-02/10 (28V RTN).
ARINC
Check A/B TRX wiring to EFIS for correct termination of A (J4-08) and B (J4-29) wires.
After both checks prove correct, and power is available to the AHRU and EFIS, then data must be
displayed (although the EFIS may still display invalid data.). If fault still apparent, further investigation
of the AHRS and/or EFIS must be carried out.
3.2
STEP 2 : HEADING AND ATTITUDE FLAGS DISPLAYED (invalid data)
Heading and Attitude are set to valid after approximately 30 seconds after power is applied to the AHRS
and a ground alignment is initiated. If not :
Check MSU Calibration Switch is in the OFF position.
CalPROM
A CalPROM must be installed and connected to 1J5.
After this check proves correct, the AHRS will set Heading and Attitude flags valid after approximately
30 seconds. If fault still apparent, further investigation of the AHRU must be carried out.
3.3
Flux–valve
STEP 3 : HEADING FLAG DISPLAYED (invalid data)
Check if the correct type of flux–valve is fitted and connected.
Check if the wiring is correct. 2 wires from AHRU (J4-02 and J4-22) to flux-valve (FV),
and 3 wires from FV to AHRU (J4-51, J4-09 and J4-30).
Check if MSU REF. IN (J4-60) is connected to MSU REF. OUT (J4-39).
After these checks prove correct, the heading flag will be set to valid after approximately 30 seconds
after alignment is initiated. If fault still apparent, further investigation of the AHRU must be carried out.
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3.4
STEP 4 : ATTITUDE FLAG DISPLAYED (invalid data)
Attitude is set to valid after approximately 30 seconds if an on the ground alignment (eg. after power-on)
is commanded.
3.5
CalPROM
A CalPROM must be installed and connected to 1J5.
Parity pin
Check equation to program Parity pin (section 1, paragraph 3.1.1).
STEP 5 : HEADING CHECK
Check that when A/C is aligned to North the heading displays 0_ "5_ after alignment.
If not check excitation voltage and/or signal wiring.
Turn A/C to align with East and check that the heading displays 090_ "5_.
If not check excitation voltage and/or signal wiring
NOTE
After alignment the A/C may be turned to any HDG, and the displayed heading must correspond
to the A/C heading "5_.
3.6
STEP 6 : ATTITUDE CHECK
Tilt AHRU right wing (starboard) down / up and check attitude display.
Tilt AHRU nose up / nose down and check attitude display.
3.7
STEP 7 : CCU CHECK
Set CCU to DG-Mode. EFIS should display that AHRU is in DG-Mode.
Turn knob clockwise to command “SLEW RIGHT” and check heading increases.
Turn knob counterclockwise to command “SLEW LEFT” and check heading decreases.
3.8
STEP 8 : SELF-TEST
Activate Self-Test and check that AHRU outputs displays of heading (15_), pitch (+5_)
and roll (45_right wing down), 180_/min. Rate of Turn, ATT, HDG and T/R flags, (refer
to section 1, paragraph 4.3).
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3.9
STEP 9 : MSU CAL-MODE SWITCH
Set MSU CAL-MODE switch to ON.
Check that attitude and heading flags are displayed, and after approximately 10 to 20
seconds the heading flag disappears (set valid).
Set MSU CAL-MODE switch to OFF.
3.10
STEP 10 : ON GROUND / IN AIR SWITCH
Set all switches to normal operation, that is :
CAL-MODE OFF,
SELF-TEST OFF,
DG /MAG to MAG,
Set ON GROUND / IN AIR switch to IN AIR.
Set SELF-TEST to ON
NOTE
The Self-Test is disabled if the A/C is IN AIR switch position, therefore the self-test data is not
displayed,
Set SELF-TEST to OFF
If all these tests are passed sucessfully then the AHRU may be assumed to function correctly.
AHRS EQUIPPED WITH A SYNCHRO CARD
If an AHRS is equipped with a synchro card (cable to J3 connected) the following check must be done ;
Check that attitude (1x) and heading (1x or 2x) synchro outputs are connected to the
synchro inputs.
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INSTALLATION / MAINTENANCE INSTRUCTION
4
LITEF LCR-92 Level 1 Test Set
The interface may be operated using the LITEF LCR-92 Level 1 RTS Test Set 309444. The Level 1 Test
Set provides the infrastructure required to perform an access to the LCR BITE history and to the AHRS
mounting misalignment correction parameters. In other words it is a tool for storing the BITE records
into file and is then able to display on a screen the BITE history information. It also enables a stimulation
of the AHRS analogue interfaces to be performed (only -2XXX and -3XXX versions).
The mounting misalignment correction feature is not available for LCR-92, P/N 124210.
ITEM LIST
The Level 1 Test Set consists of the following LITEF and commercial parts. To operate the Level 1 Test
Set an IBM compatible PC is required as stated under Hardware requirements.
LITEF Parts
P/N 309344
P/N 309345
P/N 309343
P/N 309446
P/N 309356-100-701
J1 Adapter
J4 Adapter
J5 Adapter
Serial Interface Cable
Level 1 Test Software Disk
Commercial Parts
P/N 450910-4535
P/N 450910-3173
RS232 - RS422 Converter
DB9S - DB25P RS232 - Adapter
Hardware requirements
To operate the Level 1 Test Set the following hardware is required :
IBM compatible PC/AT (486DX33 or higher recommended)
VGA Graphics Adapter
1 Serial Communication Adapter (COM1:)
Hard disk with at least 1 MByte free disk space
550 kByte of available (free) Base Memory
DOS 5.0 or higher
NOTE
At various parts of this IMI a NOTE is inserted which states that the interface may be operated
using the LITEF LCR-92 Level 1 Test Set 309444. These details laid out here are an aid to help the
technician when fault finding, or using the Test Set in general.
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INSTALLATION / MAINTENANCE INSTRUCTION
SECTION 4
REMOVAL / INSTALLATION
LITEF DOCUMENT No: 141450–0000–840
TITLE PAGE SECTION 4
November 1998
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INSTALLATION / MAINTENANCE INSTRUCTION
1
General
This section provides removal and installation procedures for the AHRU. The AHRU may be located in
the aircraft electronics rack or in an avionics bay.
Handle Units with care at all times. Mis-handling could cause damage to sensitive components of
the AHRU.
CAUTION: To prevent possible damage to the AHRS, always pull all AHRS-related aircraft
circuit breakers out (off) before removing any unit.
2
3
Removal of AHRU
1.
Pull all AHRU-related circuit breakers out (off).
2.
Disconnect 1J1 through 1J5. (Leave CalPROM secured to the mounting tray by the
retaining nylon-strap).
3.
Loosen self-torquing hold-down fastener securing AHRU in mounting tray by turning
counterclockwise.
4.
Grasp AHRU, lift slightly (but enough, so that the rear end will clear the hold-down
fastener) and pull unit straight out from mounting tray.
Installation of AHRU
CAUTION: When performing the following step, do not use sharp-pointed tools to pry out the
plug caps because the tools may pierce the plug cap and damage the connector pins.
1.
Remove cap plugs from AHRU external connectors.
CAUTION: Failure to perform the following step may cause damage to the AHRU connectors
and/or mating connectors.
2.
Ensure that all connector pins are undamaged and straight, and that no foreign objects
are in AHRU connectors and/or mating connectors.
3.
Ensure that all AHRS-related circuit breakers are off.
4.
Ensure that no tools or other items are in mounting tray or plenum.
5.
Slide AHRU into mounting tray, carefully.
6.
Engage hold-down fastener.
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7.
Tighten self-torquing hold-down fastener by turning clockwise.
8.
Connect 1J1 through 1J5. (When the CalPROM is re-attached to J5 the existing
compass compensation and mounting alignment correction constants are supplied to
the replacement AHRU)
LITEF DOCUMENT No: 141450–0000–840
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INSTALLATION / MAINTENANCE INSTRUCTION
SECTION 5
STORAGE / PACKAGING / TRANSPORTATION
LITEF DOCUMENT No: 141450–0000–840
TITLE PAGE SECTION 5
November 1998
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INSTALLATION / MAINTENANCE INSTRUCTION
1
General
This section provides storage, packaging and transportation procedures for the AHRU. The procedures
contain recommended specifications, but their use is not mandatory.
Handle Units with care at all times. Mis-handling could cause damage to sensitive components of
the AHRU.
2
Storage
The LCR-92 shall be stored in a dry dust free area. Dust free conditions can be ensured by storing the
LCR-92 in the original shipping container.
3
Packaging (References in accordance with ATA 300)
NOTE :
Items subjected to electrostatic damage shall be packaged in anti-static containers
or wraps.
All repairable items which may be removed from the aircraft and economically restored to a fully
serviceable condition shall be shipped to an airline customer in reusable containers. This requirement is
specified because of the need to protect the item through shipment, handling, and storage up to the
moment of installation, and to repeat the cycle for the life of the item.
For the purpose of this specification, reusable shipping containers are designated as follows:
Category 1
Category 2
Category 3*
Reusable for a minimum of 100 round-trips
Reusable for a minimum of 10 round-trips
Reusable for a minimum of 1 round-trip
(when used for repairable parts, refer to chapter 8 of ATA 300)
* applicable to LCR-92.
The above categories are differentiated by materials used in the container construction and tests
described in specification ATA 300.
Consideration of the special packaging, shipping, handling and storage aspects of components shall be
provided by the manufacturer because of its superior knowledge of its products.This information should
be made available sufficiently in advance of delivery of the unit to the customer to permit orderly
physical and financial planning. This information shall include shock sensitivity. magnetic field
sensitivity, hazardous materials classification, electrostatic discharge sensitivity, etc.
Manufacturers shall publish and provide size (length, width and depth or detailed outline drawings
showing all external dimensions if required due to a peculiar part configuration) and gross weight along
with any applicable information required.
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3.1
Special Packaging Requirements
The manufacturer of the unit or component shall establish and inform the customers of the shelf life and
storage instructions of its products. Items subject to abnormal deterioration, coprrosion or chemical
reaction in storage by exposure to liquids, vapours, gases, or dust shall be packaged in air-tight
containers or wraps constructed of inert materials treated to neutralize any captive air with non-toxic
results. Marking of each unit package shall be in accordance with Figure 1.
Assemblies or components which generate a magnetic field must be packaged and properly spaced in
shielding materials which will prevent the magnetic field from adversely affecting adjacent items and
instrumentation. In addition, when a part is susceptible to damage from magnetic fields, the container
shall provide necessary shielding from outside sources.
Items subject to electrostatic damage shall be packaged, marked and/or labelled in accordance with
Figure 2.
Items which are easily damaged when subjected to shock or vibration found in normal transportation
must have those fragility characteristics (the amount of “G” force to which an item can be subjected
without causing damage) documented by the manufacturer. This includes damage boundary curves or a
recommended G-levels and acceleration for a given drop height.
4
Transportation (References in accordance with ATA 300)
The units shipped from the manufacturer to the customer shall be properly classified and described,
packaged, marked, labelled, documented and in condition for transport in compliance with applicable
regulations and instructions. Location of identification markings are shown in Figure 3.
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Figure 1 Packaging of Electrostatic Discharge Sensitive Devices
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Figure 2 Electrostatic Discharge Sensitive Device Labels (typical examples)
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Figure 3 Location of Identification Markings
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THIS PAGE INTENTIONALLY LEFT BLANK
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APPENDIX 1
RTCA/DO-160C ENVIRONMENTAL QUALIFICATION FORM
LITEF DOCUMENT No: 141450–0000–840
TITLE PAGE APPENDIX 1
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INSTALLATION / MAINTENANCE INSTRUCTION
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RTCA/DO-160C ENVIRONMENTAL QUALIFICATION FORM
PNs XXXXXX-XX00
LITEF DOCUMENT No: 141450–0000–840
APPENDIX 1 Page 1
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threats
LITEF DOCUMENT No: 141450–0000–840
APPENDIX 1 Page 2
November 1998