Kanardia INDU COMBO User manual
INDU ALTIMETER
Manual
©Kanardia d.o.o.
June 2023
Revision 1.8
Altimeter — Manual
Contact Information
Publisher and producer:
Kanardia d.o.o.
Lopata 24a
SI-3000
Slovenia
Tel: +386 40 190 951
Email: info@kanardia.eu
A lot of useful and recent information can be also found on the Internet. See
http://www.kanardia.eu for more details.
Copyright
This document is published under the Creative Commons, Attribution-Share-
Alike 3.0 Unported licence. Full license is available on http://creativecommons.
org/licenses/by-sa/3.0/legalcode web page and a bit more human read-
able summary is given on
http://creativecommons.org/licenses/by-sa/3.0/. In short, the license
gives you right to copy, reproduce and modify this document if:
•you cite Kanardia d.o.o. as the author of the original work,
•you distribute the resulting work only under the same or similar license
to this one.
Credits
This document was written using TeX Live (L
A
T
E
X) based document creation
system using Kile running on Linux operating system. Most of the figures were
drawn using Open Office Draw, Inkscape and QCad applications. Photos and
scanned material was processed using Gimp. All document sources are freely
available on request under the licence mentioned above and can be obtained
by email. Please send requests to info@kanardia.eu.
Some icons used in this manual and in Horis are contributed to https://
www.flaticon.com, in particular, by Freepik, Flat icons, Maxim Basinski,
Prosymbols, Juicy Fish, Vectors Market, Maswan, Muhammad Usman.
1©Kanardia 2015-2020
Altimeter — Manual
WEEE Statement
Disposal of Waste Electrical and Electronic Equipment. This
electrical item cannot be disposed of in normal waste. Check
with your local authority for kerbside collection, or recycle
them at a recycling centre.
EU Battery Directive
This statement applies only for Altimeter which is equipped
with integrated backup battery.
This product contains a battery that is used to provide power
when the primary source of power is unavailable and is de-
signed to last the life of the product. Any attempt to service
or replace this battery should be preformed by a qualified ser-
vice tehnician.
2©Kanardia 2015-2020
Altimeter — Manual
Revision History
The following table shows the revision history of this document.
Rev. Date Description
1.8 Jun 2023 Battery lifetime and replacement section was
added. New on/off procedure for baterry backup
models.
1.7 Sep 2020 A section for the slave instruments was added.
1.6 Jul 2020 Instrument pictures update.
1.5 Aug 2018 Illumination with push button models.
1.4 Jul 2017 Backup battery option.
1.3 Mar 2016 Procedure for Illumination wheel activation.
1.2 Dec 2015 Procedure for QNH toggle and IAS auto zero.
1.1 Oct 2015 Altitude model is extended up to 20000 m.
1.0 Feb 2015 Initial release
3©Kanardia 2015-2020
Altimeter — Manual CONTENTS
Contents
1 Introduction 6
1.1 General Description . . . . . . . . . . . . . . . . . . . . . . . . 6
1.2 Technical Specification . . . . . . . . . . . . . . . . . . . . . . . 7
1.3 Options ............................... 7
1.3.1 ScaleOptions........................ 8
1.3.2 Display ........................... 9
1.3.3 Backup Battery Option . . . . . . . . . . . . . . . . . . 9
2 Installation 10
2.1 Mounting & Dimensions . . . . . . . . . . . . . . . . . . . . . . 10
2.2 Connections............................. 11
2.2.1 Static Pressure - Pst .................... 12
2.2.2 CAN Bus - CAN ....................... 13
2.2.3 Illumination......................... 13
2.2.4 Power - POWER ....................... 14
2.2.5 Green 6-Pin Connector - Backup Battery . . . . . . . . 14
3 Adjustments 14
3.1 Altitude Adjustment . . . . . . . . . . . . . . . . . . . . . . . . 14
3.2 Airspeed Adjustment - Auto Zero . . . . . . . . . . . . . . . . . 15
3.3 Toggle QNH hPa – inHg . . . . . . . . . . . . . . . . . . . . . . 16
3.4 Toggle Illumination Knob . . . . . . . . . . . . . . . . . . . . . 16
4 Maintenance & Repair 17
5 Troubleshooting 17
5.1 Freeze During Engine Start . . . . . . . . . . . . . . . . . . . . 17
6 Sensor Calibration 18
6.1 Calibration Procedure . . . . . . . . . . . . . . . . . . . . . . . 18
6.2 Pressure Altitude Calculation . . . . . . . . . . . . . . . . . . . 18
6.3 Altitude Derivative . . . . . . . . . . . . . . . . . . . . . . . . . 19
4©Kanardia 2015-2020
Altimeter — Manual CONTENTS
7 Backup Battery 20
7.1 Symbols............................... 20
7.2 NormalOperation ......................... 20
7.3 CapacityTest............................ 20
7.4 Connection Schematics . . . . . . . . . . . . . . . . . . . . . . . 21
7.4.1 Internal backup power with push button . . . . . . . . . 22
7.4.2 Internal backup power with external switch . . . . . . . 22
7.5 CAN Bus Power Schematics . . . . . . . . . . . . . . . . . . . . 23
7.6 BatteryLifetime .......................... 23
7.6.1 Replacement ........................ 24
8 Slave Version 25
9 Limited Conditions 25
9.1 Warranty .............................. 25
9.2 TSOInformation.......................... 28
5©Kanardia 2015-2020
Altimeter — Manual 1. Introduction
1 Introduction
First of all, we would like to thank you for purchasing our device. Indu
Altimeter is an electronic device, which mimics classical altimeter construction
and combines it with the state of the art electronics. This results in the best
of both worlds; a perfect and intuitive analogue reading combined with high
precision of modern electronics.
This manual describes the technical description of the unit, installation and
operation.
CAUTION: Indu Altimeter is not TSO approved as a flight
instrument.
1.1 General Description
Indu Altimeter is an electromechanical device. It consist of high precision
electronic barometric sensor, which provides static pressure information in
digital form. The electronics reads the sensor and drives two coaxial stepper
motors turning one needle each. The pressure information is also shown on a
colour LCD display. A rotating push knob is used to adjust the barometricoff-
set (aka QNH value) and to adjust LCD display brightness1. When connected
to a CAN bus Indu Altimeter outputs pressure information. An optional dim
knob can be connected to the device and it is used to adjust the brightness
of the screen.
80 mm’s display is divided linearly in 360◦scale. The long pointer is working
in 1000 m (feet) per revolution with the 20 m markings (20 feet). The short
pointer is working in 10000 m (feet) per revolution with 200 m markings (200
feet).
57 mm has a single pointer and a scale with 500 m (feet) markings.
Optionally, the 80 mm Indu Altimeter can be equipped with integrated backup
battery.
1Older models do not have push knob and a separate external knob is needed to adjust
the brightness.
6©Kanardia 2015-2020
Altimeter — Manual 1.2 Technical Specification
(a) 57 mm
(b) 80 mm
Figure 1: Front and side view with its principal dimensions.
1.2 Technical Specification
Table 1 shows some basic technical specification of Indu Altimeter.
When the instrument is equipped with a backup battery, some specifications
from the table 1 are different and correct specifications are listed in table 2
on page 9.
1.3 Options
Indu Altimeter comes in a few variants regarding scale and backup battery.
LCD display can have options, too.
7©Kanardia 2015-2020
Altimeter — Manual 1.3 Options
1.3.1 Scale Options
The instrument can be delivered with two different scales. One scale is in feet
and the other scale is in meters.
The scale must be specified at the time of order.
The QNH (baro-correction) units are also optional. You can choose between:
•hPa in the range of (590 – 1080) with one hPa step.
•inHg in the range of (17.42 – 31.89) with 0.01 inHg step.
Baro correction units can be changed by user. Please refer to section 3.3 on
page 16.
Description Value
Altitude range -500 ∼16000 m, (-1500 ∼50000 ft )
Sensor calibration standard: -500 ∼6000 m
extended: -500 ∼16000 m
Weight 57 mm: 180 g
80 mm: 240 g
Size 57 mm: 62 x 62 x 45 (64 with connectors)
mm
80 mm: 82 x 82 x 55 (74 with connectors)
mm
Operational voltage 6 ∼32 V
Power consumption 1.44 W
Current 120 mA at 12 V
60 mA at 24 V
Operating temperature -20 ∼+60 ◦C
Storage temperature -30 ∼+85 ◦C
Humidity 30 ∼90 %, non condensing
Barometric sensor 24 bit, 10 ∼1200 hPa, 20 cm resolution
QNH range 590 ∼1080 hPa, (17.42 ∼31.89 inHg)
Internal logger storage more than 50 h, 1 sinterval
Communication CAN bus, 29 bit header, 500 kbit,
Kanardia protocol
Table 1: Basic technical specifications.
8©Kanardia 2015-2020
Altimeter — Manual 1.3 Options
Description Value
Weight 305 g
Power consumption 3.84 W(when charging)
Current 320 mA at 12 V(when charging)
160 mA at 24 V(when charging)
Operating temperature -10 ∼+50 ◦C
Storage temperature -30 ∼+60 ◦C
Backup battery Lithium iron phosphate (3.3 V)
Charging time from 0 to 100 % 2 h30 min
Backup time 1 h30 min (Altimeter only)
Backup time 40 min (150 mA load on CAN bus)
Max backup power output 150 mA at 12 V(to CAN bus)
Table 2: Technical specifications for Indu Altimeter with backup battery. For
the rest of the specifications see Table 1.
1.3.2 Display
In standard configuration, LCD display shows three parameters. See the front
page photo.
•Flight level is shown on top left corner,
•altitude is shown on top right and
•QNH value is shown on bottom.
In the case of backup battery, battery status is shown in far top right corner.
If you want a different LCD display layout, you can configure it yourself
with our Customizer desktop application. This option requires Kanardia’s
Blu device for transfering the configuration from your android device to your
Indu Altimeter. Please read our Customizer Manual for more information.
1.3.3 Backup Battery Option
Optionally, Indu Altimeter can be equipped with integrated backup battery.
If the main power is switched off, the instrument obtains power from internal
battery for a limited time. In addition, the backup battery in Indu Altime-
ter can supply power for one low power external device, like Indu Airspeed
Indicator.
9©Kanardia 2015-2020
Altimeter — Manual 2. Installation
The backup battery option must be specified at the time of order. You can’t
upgrade the instrument with this option without sending it back to factory.
2 Installation
Indu Altimeter requires a standard size 57/80 mm hole in the instrument
panel. The position of the hole must ensure good access to the instrument for
the QNH adjustments and it must be always visible from the pilot’s perspec-
tive.
2.1 Mounting & Dimensions
The mounting screw holes are located on a circle of 66.5/89 mm diameter.
The instrument is mounted using three screws type M4. To prevent internal
stresses, please make sure that the instrument panel is flat.
Remove the mounting screws from the instrument and then remove the knob.
Use finger nail or sharp knife to remove the cap from the knob, but be careful
not to cut the cup away. Once the cap is removed, use flat screwdriver and
loosen the screw. Slide the knob from its axle. Figure 2 shows an example of
the knob with its cap removed.
Figure 2: Photo of the knob with its cap removed.
It is highly recommended that the instrument panel is mounted using rubber
shocks, which reduce the vibrations. Figure 3 illustrates the mounting hole.
10 ©Kanardia 2015-2020
Altimeter — Manual 2.2 Connections
Figure 4: Back view of the 57 mm instrument with connections.
(a) Standard 80 mm model.
(b) 80 mm backup model until SN
21074.
Figure 5: Back view of the 80 mm instrument with connections.
2.2.1 Static Pressure - Pst
Indu Altimeter must be connected to the static pressure source. Static pres-
sure source is usually obtained from pressure sources located on the fuselage
side surfaces or from the static port on the pitot tube.
Locate the existing tube, cut it at an appropriate place and insert a T junction.
Install a new tube from junction to the instrument.
It is highly recommended to keep the static tubing as short as possible. The
tubing must avoid sharp bends and twists. The tubing must be airtight.
12 ©Kanardia 2015-2020
Altimeter — Manual 2.2 Connections
Water must not be allowed to enter the tubing.
It is strongly recommended to label each tube before connecting to Indu
Altimeter. This will help a lot if you ever have to remove and re-install the
instrument.
2.2.2 CAN Bus - CAN
Connection to the CAN bus is optional and is not required for the normal
operation.
Use standard RJ45 ethernet cable to connect it with other Kanardia equip-
ment.
When connected to the bus, Indu Altimeter will transmit altitude, QNH and
vario to other units connected to the bus. At the same time it will serve as a
data logger - it will log most of relevant information provided on the bus.
Please note that CAN bus must be terminated. Typically, this means that
one of the connecting instruments must have a terminator plug installed.
In addition, Indu Altimeter also provides limited power (about 1 A at 12 V)
for devices connected on the CAN bus. For example: to power a slave Indu
Vertical Speed Indicator you can connect it to your Indu Altimeter via CAN
bus.
Altimeters equipped with backup battery have slightly different CAN bus
connectors. In this case only one connector provides output power, while the
second one does not. Connector that provides power is marked with red CAN
label. A device connected to this connector will also get backup power from
Indu Altimeter in the case of main power bus failure. This backup power is
limited to 150 mA at 12 V, which typically allows connection of one other
Indu instrument.
2.2.3 Illumination
LCD display brightness level can be adjusted. Here are two options: new
instruments have a push-rotate knob, while older instruments have only ro-
tating knob. When Indu Altimeter is connected to the CAN bus, the knob
adjusts brightness of all instruments connected to the bus.
On instruments with a push knob, simply push the knob, adjust the brightness
and push the knob once more.
For instruments with only rotation knob, an optional external illumination
knob can be connected to the back of the instrument. Illumination knob part
13 ©Kanardia 2015-2020
Altimeter — Manual 3. Adjustments
number is I-ALT-ILLUM and it must be ordered separately. Please refer also
to section 3.4 on page 16 for the activation procedure.
2.2.4 Power - POWER
Connect supplied connector at the back of Indu Altimeter. The connector has
a notch on one side, which protects from wrong orientation.
Connect blue lead to negative (ground) terminal and red lead to positive
(+12-24 V) terminal.
2.2.5 Green 6-Pin Connector - Backup Battery
This connector is used only with the backup battery option. Out of 6 pins,
only pin 1 and pin 2 are in use and pins 3-6 are not used.
When pins 1 and 2 are connected together (shorted), then the backup battery
circuit is active. Please refer to section 7.4 on page 21 for more details.
All altimeters with serial number 21074 or higher do not use this connector.
Most of them will not be equipped with such connector. However, some of
them may still be equipped. In this case, do not connect anything to the
green connector.
3 Adjustments
The QNH knob is used to perform some adjustments of Indu Altimeter. In
fact, this knob may be also used to adjust IAS, when such instrument is
connected to the CAN bus.
3.1 Altitude Adjustment - Static Sensor Offset
1020 →999 →1013 for hPa or 30.12 →29.50 →29.91 for inHg.
A minor sensor offset may be required in order to adjust Indu Altimeter
according to some other reference instrument. Please, follow the steps given
below in order to make the adjustment. A precise reference instrument is
needed in this procedure.
1. Set both the reference instrument and Indu Altimeter to 1013 hPa and
compare the readings. Write down the altitude shown by the reference.
14 ©Kanardia 2015-2020
Altimeter — Manual 3.2 Airspeed Adjustment - Auto Zero
2. Turn the knob on Indu Altimeter to indicate 1020 hPa (30.12 inHg) and
wait for about 3 seconds for a short cyan line to appear on the top of
LCD display.
3. Quickly turn the knob to indicate 999 hPa (29.50 inHg). A moment
later a longer cyan line appears on the top. You must reach 999 hPa
before cyan line disappears.
4. Turn the knob to select 1013 hPa (29.91 inHg) and wait for a moment.
Again, you have to reach this value before cyan line disappears.
5. Now a full cyan line appears and the LCD display is slightly altered. It
shows the offset and the altitude. Turn the knob until Indu Altimeter
shows the same altitude as the reference altimeter. Wait for cyan line
to disappear.
This completes the sensor offset procedure.
3.2 Airspeed Adjustment - Auto Zero
1020 →1030 →1013 for hPa or 30.12 →30.42 →29.91 for inHg.
In special situations, when altimeter and airspeed indicator are connected
with the CAN bus, you can use altimeter to issue zero calibration command
on the airspeed indicator. Normaly, this is not needed. You should issue this
command only, if airspeed indicator shows significant offset during pitostatic
test.
When airspeed indicator receives such command, it changes offset of the in-
ternal pressure sensor so that it shows true zero afterwards.
Important: Please make sure that aeroplane is either inside hangar or there
is absolutely no wind and that pitot tube is not covered. Failing to do so may
result in wrong offset and it may worsen airspeed precision.
The procedure is as follows:
1. Turn QNH until it shows 1020 hPa (30.12 inHg) and wait for about
three seconds for a short cyan line to appear on top of LCD display.
2. Quickly turn the knob to indicate 1030 hPa (30.42 inHg). A moment
later a longer cyan line appears.
3. Turn the knob to 1013 hPa (29.91 inHg) to complete the procedure.
Cyan line disappears and no other visual feedback is shown on either
indicator.
15 ©Kanardia 2015-2020
Altimeter — Manual 3.3 Toggle QNH hPa – inHg
3.3 Toggle QNH hPa – inHg
1020 →1025 →1013 for hPa or 30.12 →30.27 →29.91 for inHg.
Part of the LCD display is also a QNH value. This value can be shown in
hPa or in inHg units. You can change the units using next procedure:
1. Turn the knob until it shows 1020 hPa (30.12 inHg) and wait for about
three seconds for a short cyan line to appear on top of LCD display.
2. Quickly turn the knob to indicate 1025 hPa (30.27 inHg). A moment
later a longer cyan line appears.
3. Turn the knob to 1013 hPa (29.91 inHg) to complete the procedure.
Observe the units and values next to QNH. They changed from hPa to
inHg and vice versa.
3.4 Toggle Illumination Knob
1020 →1035 →1013 for hPa or 30.12 →30.56 →29.91 for inHg.
This section applies only to instruments without push/rotate knob.
If the external illumination knob does not work – screen does not react on the
knob, try the following procedure. This procedure enables remote illumination
knob if it was not enabled or disables illumination knob, if it was enabled.
1. Turn QNH until it shows 1020 hPa (30.12 inHg) and wait for about
three seconds for a short cyan line to appear on top of LCD display.
2. Quickly turn the knob to indicate 1035 hPa (30.56 inHg). A moment
later a longer cyan line appears.
3. Turn the knob to 1013 hPa (29.91 inHg) to complete the procedure.
4. Finally, you need to turn off Indu Altimeter and then back on in order
to activate the change.
16 ©Kanardia 2015-2020
Altimeter — Manual 4. Maintenance & Repair
4 Maintenance & Repair
No special maintenance is required.
The instrument has no serviceable parts inside. In the case of malfunction,
it must be sent to factory for a repair. A backup battery replacement is an
exception. See section 7.6.1 for more details.
Altimeters equipped with a backup battery shall undergo battery capacity
check annually. The procedure is described in section 7.3.
5 Troubleshooting
5.1 Freeze During Engine Start
In certain aircraft installations instrument freezes and then reboots itself,
when some large current consumers are switched on. This is caused by a very
short voltage drop as a consequence of the consumer’s power demand.
A simple electronic circuit illustrated in Figure 6 may help in this case. The
circuit consist of two elements.
•The diode prevents reverse flow from the capacitor. We recommend
Schottky Diode 1N5818G. You can also use some other diode, which has
a low voltage drop, 1 A forward current and at least 20 V of blocking
voltage.
•The capacitor serves for a very short energy reserve. Use an aluminium
electrolytic capacitor with about 1000 µF, at least 25 V and at least
100 ◦C working temperature.
Instrument
+12 V
GND
Diode
1N5818G
Capacitor
1000 μF, 25V, 108°C
Figure 6: Circuit that may prevent sudden voltage drops in certain installa-
tions.
17 ©Kanardia 2015-2020
Altimeter — Manual 6. Sensor Calibration
6 Sensor Calibration & Altitude Calculation
6.1 Calibration Procedure
Each unit is factory calibrated against reference barometer at different pres-
sure points. In standard calibration range we calibrate in following pressure
sequence: 1100, 1000, 900, 800, 700, 600, 500, 400, 280, 550, 650, 750, 850,
950 and 1050 hPa. These measurements are then repeated at different tem-
peratures ranging from -10 to 60 ◦C in 7 ◦C steps.
Please note that FAA Part 43, Appendix E does not require calibration/verification
at different temperatures. But temperature calibration is essential for any
electronic sensor.
This means that each instrument is calibrated against 13 ·11 = 143 different
temperature - pressure pairs. The least squares method is then applied on
this results in order to obtain corrections coefficients. A two dimensional,
third degree polynomial is used for the correction model.
You can’t change calibration parameters, but you can adjust the altitude.
Please refer to the section 3.1 for more details.
6.2 Pressure Altitude Calculation
Pressure altitude is calculated according to the ISA 1976 model of athmo-
sphere. First two athmosphere layers are used; throposphere and thropopause.
The throposphere is modeled by equation (1) up to 11000 meters of geopoten-
tial altitude. The thropopause layer is modeled by equation (2) up to 20000
meters of geopotential altitude.
As the pressure sensor is calibrated down to 100 hPa (about 16000 meters)
altitudes above 16000 meters are not reliable.
p=p0T0+T′
0·z
T0
−g0
RT ′
0(1)
p=p1exp −g0(z−z1)
RT1(2)
The equations converts geopotential altitude into pressure. Here zmeans
geopotential altitude, g0= 9.806645 m/s2is gravity constant, R= 287.0528
N·m/kg ·K. is gas constant for dry air, p0= 1013.25 hPa is standard
18 ©Kanardia 2015-2020
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