Thommen AD20 User manual

,rfidfrt'E\*
REVT.ETHOMMENAG
CH-4437 Waldenburg
07-Sep-2009
AD20 Standby Altimeter p age 1 or 72
Document No: AD-l NSOP-800 Revision: 1.6
TITLE: INSTALLATION AND OPERATION MANUAL
AD20 Standby Altimeter
DOCUMENT NO.: AD-INSOP-8O0
REVISION:
PRCJECT:
1.6
Solid State Flight lnstrument Family
MANUFACTURER: REVUETHOMMENAG
CH-4437 Waldenburg
Switzerland
ISSUING OFFICE: Development Department
Näme Si,gnature Date
Author: M.Baumann /n9"tfto-^* 07-Sep-2009
Project Management: R. Wehrli /.ü/u{ 22-Sep-2009
Development M anagement: R. Wehrli /.ü/u{ 22-Sep-2009
Quality Management: O. Thommen en^ zg" ? äf
@ Copyright by REVUE THOMMEN AG, CH-4437 Waldenburg Switzerland

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 2 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
Change History
Rev. Modification / Description Date Author checked
1.0 First release of document 18-Aug-2006 R. Eichhorn R. Wehrli
1.1 Minor corrections 09-Nov-2006 R. Wehrli M. Baumann
1.2 - Metric unit selection discrete input
added
- RF susc. Cat. [WW] and harness with
unshielded power wires added
28-Feb-2007 R. Wehrli M. Baumann
1.3 - lighting curve selection numbers
corrected
- lighting curve adjustment changed
- env. Qualification Explosion Cat. X
corrected
12-Sep-2007 R. Wehrli M. Baumann
1.4 - HIRF-Test added acc. to FAA AC No
20-158 (DO-160D Section 20.0, Cat. XW
(with special test levels)
08-Jan-2008 M. Baumann R. Wehrli
1.5 Correct baro setting value in section
2.2.2.1.4
05-May-2008 M. Baumann R. Wehrli
1.6 Update section 2.4.1 07-Sep-2009 M. Baumann R. Wehrli

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 3 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
TABLE OF CONTENTS
1SECTION I.....................................................................................................................................10
1.1 Introduction..............................................................................................................................10
1.1.1 Purpose of the manual ...................................................................................................... 10
1.1.2 Equipment Specification.................................................................................................... 10
1.1.2.1 Applicable Documents .................................................................................................. 10
1.1.2.2 Identification ..................................................................................................................13
1.1.2.2.1 Type Identification Drawing .................................................................................... 13
1.1.2.2.2 Identification/Name Plate ........................................................................................ 14
1.1.2.3 Installation Kit ................................................................................................................15
1.1.3 Technical Specification ..................................................................................................... 15
1.1.4 Equipment Dimensions ..................................................................................................... 16
1.1.5 Pneumatic Pressure Port .................................................................................................. 17
1.1.6 Interface Block diagram .................................................................................................... 18
2SECTION II....................................................................................................................................19
2.1 General Information................................................................................................................19
2.2 Description...............................................................................................................................19
2.2.1 Instrument Description ...................................................................................................... 19
2.2.2 Functional Description....................................................................................................... 20
2.2.2.1 Display ........................................................................................................................... 21
2.2.2.1.1 Digital Altitude Display ............................................................................................ 21
2.2.2.1.2 Altitude Pointer........................................................................................................ 21
2.2.2.1.3 Altitude Scale Setting ft/m....................................................................................... 21
2.2.2.1.4 Baro Setting Display ............................................................................................... 21
2.2.2.1.5 Baro Scale Setting inHg/hPa .................................................................................. 21
2.2.2.1.6 Battery Engagement Indicators A, B and C............................................................ 21
2.2.2.2 Controls ......................................................................................................................... 22
2.2.2.2.1 Baro Setting Knob ................................................................................................... 22
2.2.2.2.2 Push to Standard Knob........................................................................................... 22
2.2.2.2.3 UNIT Button............................................................................................................. 22
2.2.2.2.4 TEST Button............................................................................................................ 22
2.3 Operations................................................................................................................................23
2.3.1 Theory of Operation .......................................................................................................... 23
2.3.1.1 Power Supply ................................................................................................................ 23

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 4 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
2.3.1.2 Micro Controller ............................................................................................................. 23
2.3.1.3 ARINC 429 Interface (optional)..................................................................................... 23
2.3.1.4 Pointer Positioning ........................................................................................................ 24
2.3.1.5 Dial and Display ............................................................................................................ 24
2.3.1.5.1 Dial and Display Lighting Default Function............................................................. 25
2.3.1.6 Configuration Identification............................................................................................ 26
2.3.1.7 RS232 Serial Interface .................................................................................................. 26
2.3.1.8 Operating Range, Limiting Values and Tolerances...................................................... 26
2.3.1.9 Battery Status Display Overview (optional) .................................................................. 27
2.3.1.10 Digital Display............................................................................................................ 28
2.4 TESTING...................................................................................................................................30
2.4.1 Startup BIT Sequence....................................................................................................... 30
2.4.1.1 Display of all LCD segments / white lighting................................................................. 30
2.4.1.2 Display of battery charge / amber lighting (optional) .................................................... 30
2.4.1.3 Display Config ID and A/C type .................................................................................... 31
2.4.1.4 Display current altitude and baro setting ...................................................................... 31
2.4.2 Built-in-Test ....................................................................................................................... 32
2.4.2.1 BIT Overview ................................................................................................................. 32
2.4.2.2 Start Up BIT................................................................................................................... 32
2.4.2.3 Initiated BIT ...................................................................................................................32
2.4.2.4 Continuous BIT.............................................................................................................. 32
2.4.3 Failure Modes.................................................................................................................... 33
2.4.3.1 Fault Code Handling Overview ..................................................................................... 33
2.4.3.2 Non critical or tolerable Failures ................................................................................... 34
2.4.3.3 Critical Failure Indication............................................................................................... 35
2.4.3.4 Power Failure ................................................................................................................ 35
3SECTION III...................................................................................................................................36
3.1 Approvals.................................................................................................................................36
3.1.1 General.............................................................................................................................. 36
3.1.2 Instructions for Continued Airworthiness .......................................................................... 36
3.1.3 Environmental Qualification .............................................................................................. 37
3.1.3.1 Electromagnetic Environment (EME)............................................................................ 40
3.1.3.2 Electromagnetic compatibility (EMC)............................................................................ 40
3.1.3.3 Electromagnetic interference (EMI) .............................................................................. 40
3.1.3.4 Pointer position error ..................................................................................................... 40
3.1.3.5 Scale error .....................................................................................................................40

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 5 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
3.1.3.6 Hysteresis......................................................................................................................40
4SECTION IV..................................................................................................................................41
4.1 Installation................................................................................................................................41
4.1.1 General.............................................................................................................................. 41
4.1.2 Unpacking and Inspecting................................................................................................. 41
4.1.3 Pre and Post Installation Check........................................................................................ 41
4.1.4 Electrical Interface............................................................................................................. 41
4.1.4.1 Overview of electrical interface ..................................................................................... 41
4.1.4.2 Power Control (DC Primary) ......................................................................................... 41
4.1.4.3 Power Consumption...................................................................................................... 41
4.1.4.4 Power Failure indication................................................................................................ 42
4.1.4.5 Groundings and Shielding............................................................................................. 42
4.1.4.5.1 Harness with shielded power wires, RF Susceptibility Cat. [YY] ........................... 42
4.1.4.5.2 Harness with unshielded power wires, RF Susceptibility Cat. [WW] ..................... 43
4.1.5 Electrical connector ........................................................................................................... 44
4.1.5.1 Pin Assignments............................................................................................................ 44
4.1.5.2 Wiring Diagram (shielded power wires, RF Susc. Cat. [YY]) ....................................... 46
4.1.5.3 Wiring Diagram (unshielded power wires, RF Susc. Cat. [WW]) ................................. 47
4.1.6 Digital Data Interface......................................................................................................... 48
4.1.6.1 ARINC 429 (optional) .................................................................................................... 48
4.1.6.1.1 ARINC 429 Data bus Interface ............................................................................... 48
4.1.6.1.2 ARINC 429 BIT Rate............................................................................................... 48
4.1.6.1.3 ARINC Label Formats............................................................................................. 48
4.1.6.1.4 Label 203 (Pressure Altitude) ................................................................................. 49
4.1.6.1.5 Label 204 (Baro corrected altitude #1) ................................................................... 50
4.1.6.1.6 Label 217 (Static Pressure ) ................................................................................... 51
4.1.6.1.7 Label 234 (Baro correction hPa #1)........................................................................ 52
4.1.6.1.8 Label 235 (Baro correction inHg #1)....................................................................... 53
4.1.6.1.9 Label 270 (Discrete word #1).................................................................................. 54
4.1.6.1.10 Label 350 (Maintenance word #1) (Provision) ..................................................... 55
4.1.6.2 Discrete I/O’s ................................................................................................................. 56
4.1.6.2.1 Discrete Inputs ........................................................................................................ 56
4.1.6.2.2 Discrete Input Functions ......................................................................................... 56
4.1.6.2.3 Aircraft Type Selection............................................................................................ 56
4.1.6.2.4 Discrete Outputs ..................................................................................................... 57
4.1.6.3 RS232 Serial Interface .................................................................................................. 57

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 6 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
5SECTION V ...................................................................................................................................58
5.1 Trouble shooting.....................................................................................................................58
5.2 Maintenance.............................................................................................................................59
5.3 Manual Maintenance Mode.....................................................................................................60
5.3.1 Entering Manual Maintenance Mode ................................................................................ 60
5.3.2 Display 1: Battery Capacity Test (provision)..................................................................... 60
5.3.3 Display 2: High Resolution Altitude................................................................................... 61
5.3.4 Display 3: Lighting Curve Selection .................................................................................. 62
5.3.5 Display 4: Lighting Curve Adjustment............................................................................... 64
6APPENDICES...............................................................................................................................67
6.1 APPENDIX I: Function Overview...........................................................................................67
6.2 APPENDIX II: Failure Codes...................................................................................................70
6.3 APPENDIX III: Altimeter Calibration Table ...........................................................................72
LIST OF FIGURES
FIG.1-1 TYPE IDENTIFICATION DRAWING................................................................................................ 13
FIG.1-2 EQUIPMENT SIDE VIEW ............................................................................................................. 16
FIG.1-3 EQUIPMENT BACK VIEW AND EQUIPMENT CUT-OUT ................................................................... 17
FIG.1-4 INTERFACE BLOCK DIAGRAM .................................................................................................... 18
FIG.2-1 FRONT VIEW ............................................................................................................................. 20
FIG.2-2 DIAL AND DISPLAY LIGHTING ..................................................................................................... 25
FIG.2-3 DISPLAY OF ALL LCD SEGMENTS /WHITE LIGHTING ................................................................... 30
FIG.2-4 DISPLAY OF BATTERY CHARGE /AMBER LIGHTING (OPTIONAL) ................................................... 30
FIG.2-5 DISPLAY CONFIG ID AND A/C TYPE ........................................................................................... 31
FIG.2-6 DISPLAY CURRENT ALTITUDE AND BARO SETTING ...................................................................... 31
FIG.2-7 INDICATION OF NON-CRITICAL OR TOLERABLE FAILURES............................................................ 34
FIG.2-8 INDICATION OF CRITICAL FAILURES ........................................................................................... 35
FIG.4-1 HARNESS SHIELDING RF CAT.[YY] .......................................................................................... 43
FIG.4-2 WIRING DIAGRAM (SHIELDED POWER WIRES) ............................................................................ 46
FIG.4-3 WIRING DIAGRAM (UNSHIELDED POWER WIRES) ........................................................................ 47
FIG.5-1 BATTERY TEST DISPLAY............................................................................................................ 61
FIG.5-2 HIGH RESOLUTION ALTITUDE .................................................................................................... 61

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 7 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
FIG.5-3 LIGHTING CURVE SELECTION DISPLAY ...................................................................................... 62
FIG.5-4 LIGHTING CURVE ADJUSTMENT ................................................................................................. 64
FIG.5-5 LIGHTING CURVE ADJUSTMENT DISPLAY ................................................................................... 65
LIST OF TABLES
TABLE 1-1 CERTIFICATION STANDARDS .................................................................................................. 11
TABLE 1-2 MIL-STANDARDS ................................................................................................................... 11
TABLE 1-3 OTHER STANDARDS .............................................................................................................. 12
TABLE 1-4 REVUE THOMMEN STANDARDS,PLANS AND DOCUMENTS ................................................. 12
TABLE 1-5 REFERENCED DOCUMENTS (GUIDANCE MATERIAL) ............................................................... 12
TABLE 1-6 INSTALLATION KIT.................................................................................................................. 15
TABLE 1-7 TECHNICAL SPECIFICATION.................................................................................................... 15
TABLE 1-8 PNEUMATIC PRESSURE PORT................................................................................................ 17
TABLE 2-1 FUNCTIONAL DESCRIPTION.................................................................................................... 20
TABLE 2-2 ARINC 429 LABELS .............................................................................................................. 24
TABLE 2-3 DIAL AND DISPLAY LIGHTING.................................................................................................. 25
TABLE 2-4 OPERATING RANGE,LIMITING VALUES AND TOLERANCES ...................................................... 26
TABLE 2-5 BATTERY STATUS DISPLAY OVERVIEW .................................................................................. 27
TABLE 2-6 DIGITAL DISPLAY IN FEET....................................................................................................... 28
TABLE 2-7 DIGITAL DISPLAY IN METER .................................................................................................... 28
TABLE 2-8 ALTITUDE DISPLAY RESOLUTION IN FEET ................................................................................ 29
TABLE 2-9 ALTITUDE DISPLAY RESOLUTION IN METER ............................................................................. 29
TABLE 2-10 BUILT-IN TEST OVERVIEW.................................................................................................... 32
TABLE 2-11 FAULT CODE HANDLING....................................................................................................... 33
TABLE 3-1 ENVIRONMENTAL QUALIFICATION........................................................................................... 39
TABLE 4-1 POWER CONSUMPTION.......................................................................................................... 42
TABLE 4-2 PIN ASSIGNMENTS................................................................................................................. 45
TABLE 4-3 ARINC 429 DATA BUS INTERFACE ........................................................................................ 48
TABLE 4-4 LABEL 203 (PRESSURE ALTITUDE)......................................................................................... 49
TABLE 4-5 LABEL 204 (BARO CORRECTED ALTITUDE #1) ........................................................................ 50
TABLE 4-6 LABEL 217 (STATIC PRESSURE )............................................................................................ 51
TABLE 4-7 LABEL 234 (BARO CORRECTION HPA #1) ............................................................................... 52
TABLE 4-8 LABEL 235 (BARO CORRECTION INHG #1).............................................................................. 53
TABLE 4-9 LABEL 270 (DISCRETE WORD #1) .......................................................................................... 54
TABLE 4-10 LABEL 350 (MAINTENANCE WORD #1) (PROVISION) ............................................................. 55
TABLE 4-11 DISCRETE INPUTS VOLTAGE LEVELS.................................................................................... 56

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 8 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
TABLE 4-12 DISCRETE INPUTS FUNCTIONS ............................................................................................. 56
TABLE 4-13 AIRCRAFT TYPE SELECTION ................................................................................................ 57
TABLE 4-14 DISCRETE OUTPUTS ............................................................................................................ 57
TABLE 5-1 TROUBLE SHOOTING PROCEDURES ....................................................................................... 58
TABLE 5-2 MAINTENANCE MODES .......................................................................................................... 59
TABLE 5-3 LIGHTING CONDITIONS ........................................................................................................... 62
TABLE 6-1 FUNCTION OVERVIEW ............................................................................................................ 69
TABLE 6-2 FAILURE CODES .................................................................................................................... 71
TABLE 6-3 ALTIMETER CALIBRATION TABLE ............................................................................................ 72

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 9 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
LIST OF ABBREVIATIONS AND ACRONYMS
Abbreviation Description
A/C Aircraft
Abs Absolute
ARINC Aeronautical Radio Inc.
ASCII American Standard Code for Information Interchange
BIT Built In Test
CPU Central Processing Unit
DC Direct Current
EASA European Aviation Safety Agency
EMI Electro Magnetic Interference
ETSO European Technical Standard Order
FAA Federal Aviation Administration (USA)
FAR Federal Aviation Regulation
FI Flight Instruments
FIG Figure
HW Hardware
ICAO International Civil Aviation Organization
IF Interface
LCD Liquid Crystal Display
N.A. Not applicable
NC Not Connected
REV Revision
RTCA Radio Technical Commission for Aeronautics
RTW REVUE THOMMEN AG, Waldenburg
SW Software
TBD To Be Defined
TSO Technical Standard Order
HIRF High Intensity Radiated Field

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 10 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
1 Section I
1.1 Introduction
1.1.1 Purpose of the manual
This manual provides the specifications, installation instructions, equipment operation and system
maintenance in details for the REVUE THOMMEN AD20 Standby Altimeter. This manual also defines
interface design requirements including mechanical and electrical characteristics for the AD20
Standby Altimeter.
The description and procedures are covered in different topics as shown in the Table of Contents,
and the troubleshooting procedures are given under sections to identify the fault and failure
conditions of the unit with the interface systems.
The procedures in this manual are to be performed by qualified personnel familiar with REVUE
THOMMEN AD20 Standby Altimeter Equipment.
Note 1 : This manual is applicable for all Solid State Flight Instruments Family with part number as
AD20.().
1.1.2 Equipment Specification
1.1.2.1 Applicable Documents
The following table shows the list of relevant applicable documents which forms the basis of
approvals of the REVUE THOMMEN AD20 Standby Altimeter.
Certification Standards
Identifier Document Title Issue / Date
FAR 23 Airworthiness Standards: Normal, Utility, Acrobatic, and
Commuter Category Airplanes
1 Feb. 2001
CS-23 Normal, Utility, Aerobatic, and Commuter Category
Airplanes
14/11/2003
AC 23.1309-1C Equipment, Systems, and Installations in Part 23 Airplanes 12/03/99
FAR 25 Airworthiness Standards: Transport Category Airplanes 9/14/2000
CS 25 Certification Specifications for Large Airplanes 17/10/2003
FAR 25.1333 Instrument systems
AC 25-11 Transport Category Airplane Electronic Display Systems 16/07/87
AMJ 25-11 Transport Category Airplane Electronic Display Systems 27 May 1994
AMJ 25.1309 System Design and Analysis 11/05/90
FAR 27 Airworthiness Standards: Normal Category Rotorcraft Jan. 21, 2000

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 11 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
Identifier Document Title Issue / Date
CS-27 Certification Specifications for Small Rotorcraft 14/11/2003
AC 27-1B Certification of Normal Category Rotorcraft 9/30/99
TSO-C10b Altimeter, Pressure Actuated Sensitive Type 01/09/59
ETSO-C10b Altimeter, Pressure Actuated Sensitive Type 24.10.03
SAE AS392C Altimeters, Pressure Actuated Sensitive Type 1 February
1959
SAE AS8009B Pressure Altimeter Systems 2005-09
ED-26
(Edition 2)
Minimum Performance Specification for Airborne Altitude
Measurement and Coding Systems
30/03/79
ARINC 706-4 Mark 5 Subsonic Air Data System 11/01/88
ED-12B
RTCA/DO-178B
Software Considerations in Airborne Systems and
Equipment Certification
01/12/92
ED-14D
RTCA/DO-160D
Environmental Conditions and Test Procedures for Airborne
Equipment with
- Change 1
- Change 2
- Change 3
29/07/97
14.12.2000
12.06.2001
05.12.2002
Table 1-1 Certification Standards
MIL Standards
Doc-No. Document Title
MIL-C-14806 Coating, reflection reducing, for instrument cover glasses and lighting wedges
MIL-C-26482G Connectors, Electrical
MIL-L-27160C Lighting, Integral, Aircraft Instrument Cover Glasses and Lighting Wedges
MIL-STD-810E Method 505.3, Solar Radiation (Sunshine)
MS 33649 Bosses, Fluid Connection - Internal Straight Thread
Table 1-2 MIL-Standards

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 12 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
Other Standards
Doc-No. Document Title
FED-STD-595a Colors
ANSI/J-STD-001 Standard Requirements for Electrical and Electronic Assemblies
Table 1-3 Other Standards
REVUE THOMMEN Standards, Plans and Documents
Doc-No. Document Title
ADMD-RCP-930 ADMD2X Re-Certification Plan
ADAC-PSA-420 ADAC32 Plan for Software Aspects of Certification
ADAC-SVP-420 ADAC32 Software Verification Plan
ADMD-FME-931 ADMD2X Safety Analysis / FMEA Report
FI-QAP-020 FI Software Quality Assurance Plan
FI-CMP-020 FI Software Configuration Management Plan
RT-SRS-020 RT Software Requirements Standards
RT-SDS-020 RT Software Design Standards
RT-SCS-020 RT Software Code Standards
RTW-MM-05 REVUE THOMMEN Management Manual
Table 1-4 REVUE THOMMEN Standards, Plans and Documents
Referenced Documents (Guidance Material)
Identifier Document Title Issue / Date
ARINC 607-3 Design Guidance for Avionic Equipment 12/08/98
ARINC 429 Mark 33 Digital Information Transfer System 9/95
ED-80
RTCA/DO-254
ED-80 / RTCA/DO-254 Design Assurance Guidance for
Airborne Electronic Hardware
04/00
FAA
Memorandum
Information: Policy Statement with respect to All Electrical
Attitude, Altitude, Direction and Airspeed Systems using
Battery Standby Power
APR 27 2001
Table 1-5 Referenced Documents (Guidance Material)

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AD20 Standby Altimeter
Page 13 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
Order of precedence
In the event of a conflict between the text of this specification and the references cited herein, (except
for associated detail specifications or specification sheets), the text of this specification shall take
precedence. Nothing in this specification, however, shall supersede applicable laws and regulations
unless a specific exemption has been obtained.
1.1.2.2 Identification
1.1.2.2.1 Type Identification Drawing
Altimeter 2 inches, Pointer / LCD
ARINC metal case 408 2ATI,
bezel black acc. FED-STD-595a, No. 37038
Dial markings are lusterless white
acc. FED-STD-595a, No. 37875
Measuring range -1'000 ... 55'000 feet
lighting 5 VDC
lighting white only
see spec. Code
AD20.32.55F.05.1.AP
AD20
.3
. -2
.55F
.05
.1
.AP
-acc. TSO-C10b
-pneumatic port
"S" 9/16"-18UNJF-3B (MS 33649-6)
-electrical connector 19-pin
MS 3112E-14-19P
(MIL-C-26482G Series 1)
-Power supply 28 VDC (< 8W)
-Li Ion Battery
-RS232 Maintenance IF
-TEST Discrete Input
-Battery Activation Discrete Input
-Warning Flag Valid Discrete Output
-numerals and letters acc.
Norme Francaise
REVUE THOMMEN AG
AP
21 30150 14
AD20.32.55F.05.1.AP
Altimeter
Standby, with Backup Battery
ranges and configurations
refer to Technical Checklist
A TL
U
N
I
T
BARO
TEST
P
U
S
H
S
T
D
S
Fig. 1-1 Type Identification Drawing

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 14 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
1.1.2.2.2 Identification/Name Plate
The Identification/Name plate is attached on the instrument case of AD20 Standby Altimeter. The
sample of Identification/Name plate of AD20 Standby Altimeter is shown below:
ETSO/TSO-Nameplate (sample)
REVUE THOMMEN AG
CH-4437 WALDENBURG
ALTIMETER
CERTIFIED ETSO/TSO-C10b WT 550 gm (1.2 lbs)
RTCA/DO-160D ENV.CAT. [F1]CBB[(TB1)(TR)]XWFDFSZZAZZ[YY]M[A3J33]XXA
RTCA/DO-178B LEVEL A CONFIG ID
PART/TYPE NO AD20.32.55F.05.1.AP - 85XX
SER NO xxxxxxx PWR SUPPLY 28 VDC
RANGE -1'000 … 55'000 FEET LIGHTING SUPPLY 5 VDC
MFR DATE month / year
SWISS MADE PHONE [phone] [email protected]
Version/MOD Label (sample)
REVUE THOMMEN AG
CH-4437 WALDENBURG
HW Version 1.XX
SW Version 6.XX
00 01 02 03 04 05 06 07 08 09 10 11 12 13 14 15 16
MOD A B C D E F G H I J K L M N P R S
SWISS MADE PHONE [phone] [email protected]
NOTE: The configuration ID code allows identifying the individual configuration of the instrument.
Instruments with the same config. ID codes are identical.

REVUE THOMMEN AG
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AD20 Standby Altimeter
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07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
1.1.2.3 Installation Kit
Part Number Quantity Description
AD20.XX.XXX.XX.X.XX 1 REVUE THOMMEN AD20 Standby Altimeter
AD-INSOP-800 1 REVUE THOMMEN AD20 Standby Altimeter
Installation and Operation Manual
AD-DDP-XXX 1 Declaration of Design and Performance
Table 1-6 Installation Kit
NOTE: As per ordered by the Installer.
1.1.3 Technical Specification
Characteristics Specifications
Primary Power 28 VDC
During startup max. 4.0 W / 140mA
Normal operation max. 1.7 W / 60mA
Emergency Power 28 VDC
Lighting power 5 VDC (opt. 28 VDC)
Physical Dimension
Height 56.13 mm (2.2 in)
Width 56.13 mm (2.2 in)
Length 179 mm (7.047 in)
Table 1-7 Technical Specification

REVUE THOMMEN AG
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AD20 Standby Altimeter
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07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
1.1.4 Equipment Dimensions
Fig. 1-2 Equipment Side View
NOTE: The dimensions are in millimeters or inches
NOTE: Not to scale.

REVUE THOMMEN AG
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AD20 Standby Altimeter
Page 17 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
S
Fig. 1-3 Equipment Back View and Equipment cut-out
1.1.5 Pneumatic Pressure Port
Mechanical
1) Pressure range Over pressure capability
Static Port ”S” 1/2“-20UNJF-3B
(MS33649-5)
100 … 1050 hPa abs 1500 hPa abs
Static Port ”S” 9/16“-18UNJF-3B
(MS33649-5)
100 … 1050 hPa abs 1500 hPa abs
Table 1-8 Pneumatic Pressure Port
1) Note: refer to the Type Identification Drawing of your specific instrument type for the
correct pressure port dimension.

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 18 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
1.1.6 Interface Block diagram
Fehler! Keine gültige Verknüpfung.
Fig. 1-4 Interface Block Diagram

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 19 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
2 Section II
2.1 General Information
This Section provides the description, the theory of operation and functional modes required to
understand and operate of AD20 Standby Altimeter unit. Refer to the following paragraph for the brief
description of the instrument. The AD20 Standby Altimeter belongs to the Solid State Flight
Instruments Family of REVUE THOMMEN AG.
2.2 Description
2.2.1 Instrument Description
The implementation of the AD20 Standby Altimeter provides measured barometric (corrected)
altitude. The static pressure is sensed by the integrated solid state pressure sensor and computed
internally. The instrument provides both dedicated digital liquid crystal display (LCD) and analog
pointer which features high intensity backlighting for daylight conditions. The altitude can be
displayed in both metric units as well as English (see section II, part 2, B.2.4).
It can be configured for different installations as per parameter upload via the RS232 serial
maintenance interface. The corrected Altitude is displayed in digital format on a high contrast LCD
and by a stepper motor driven pointer.
The extensive Built-In-Test (BIT) guarantees safe operation using watch dog circuitry on each power
on. The low power consumption and its low weight have been optimized for applications in state-of-
the-art avionics.
The REVUE THOMMEN AD20 Standby Altimeter is a simple designed modular unit and hence
having easy maintenance. By RS232 serial maintenance interface the AD20 Standby Altimeter can
be configured for different applications as per the aircraft requirements. Therefore its application
range reaches from Business Aviation up to Regional Aircraft, Transporters and Helicopters.
The REVUE THOMMEN AD20 Standby Altimeter meets or exceeds the requirements of ETSO/TSO-
C10b.

REVUE THOMMEN AG
CH-4437 Waldenburg
AD20 Standby Altimeter
Page 20 of 72
07-Sep-2009 Document No: AD-INSOP-800 Revision: 1.6
2.2.2 Functional Description
Fig. 2-1 Front View
Display Controls
A Digital Altitude Display G Baro Setting / Push-to-Standard Knob
B Altitude Pointer H UNIT Button
C Altitude Scale Setting ft / m I TEST Button
D Baro Setting Display
E Baro Scale Setting inHg / hPa
F Battery Engagement Indicators
Table 2-1 Functional Description
B
A
D
G I
H
C
E
F