Madur GA-21 Plus Operating Manual

FLUE GAS ANALYSER
GA-21 plus

Operating manual

Version: 2.1
06/2017

www.madur.com Manual GA-21Plus

Index

1. Introduction................................................................................................................................................4

1.1. Use of this operating manual..............................................................................................................4

2. Maintenance...............................................................................................................................................5

2.1. Gas sensors........................................................................................................................................5

2.2. Gas system.........................................................................................................................................5

2.3. Battery.................................................................................................................................................5

2.4. Service intervals..................................................................................................................................6

2.5. Errors during operation.......................................................................................................................6

2.6. Switching off after use.........................................................................................................................6

3. General information..................................................................................................................................7

4. Construction..............................................................................................................................................9

4.1. Elements of gas circuit........................................................................................................................9

4.1.1. Gas probe with in-line filter.........................................................................................................9

4.1.2. Gas pump..................................................................................................................................10

4.1.3. Gas chamber.............................................................................................................................10

4.2. Measurement system........................................................................................................................10

4.2.1. Gas sensors..............................................................................................................................10

4.2.2. Ambient temperature sensor.....................................................................................................12

4.2.3. Flue gas temperature sensor....................................................................................................12

4.2.4. Gas chamber temperature sensor............................................................................................12

4.2.5. Differential pressure sensor......................................................................................................12

4.2.6. Analogue inputs.........................................................................................................................12

4.3. Data input/output system..................................................................................................................14

4.3.1. Keyboard...................................................................................................................................14

4.3.2. Display.......................................................................................................................................16

4.3.3. Printer........................................................................................................................................16

4.3.4. Interface RS232C......................................................................................................................16

4.3.5. Power supply.............................................................................................................................17

5. Operation..................................................................................................................................................18

5.1. Use of the keyboard..........................................................................................................................18

5.1.1. Description of the keys..............................................................................................................18

5.1.2. Selecting menu options.............................................................................................................19

5.1.3. Entering numbers......................................................................................................................20

5.1.4. Editing text................................................................................................................................20

5.2. Basic operating instructions..............................................................................................................21

5.2.1. Setting-up the analyser.............................................................................................................21

5.2.2. Switching on..............................................................................................................................21

5.2.3. Switching off / standby..............................................................................................................21

5.2.4. Initial calibration........................................................................................................................23

5.2.5. Measurement parameters.........................................................................................................24

5.2.5.1. Fuel selection......................................................................................................................25

5.2.5.2. Averaging time....................................................................................................................27

5.2.5.3. Reference oxygen parameters (O2R)................................................................................27

5.2.5.4. Boiler parameters...............................................................................................................28

5.3. Displaying the measurement results.................................................................................................29

5.3.1. Current values...........................................................................................................................29

5.3.2. Averaged values........................................................................................................................30

5.3.3. The averaging process..............................................................................................................31

5.4. Pressure/Draft measurements..........................................................................................................32

5.5. Soot (smoke) Measurement..............................................................................................................33

5.6. Options..............................................................................................................................................34

5.6.1. Device info................................................................................................................................35

5.6.2. Sensors.....................................................................................................................................36

5.6.2.1. Sensor CO (only in dual CO sensor configuration)............................................................36

5.6.2.2. CO range............................................................................................................................37

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5.6.2.3. O2 cell calibration...............................................................................................................37

5.6.2.4. External channels...............................................................................................................38

5.6.2.5. Sensor calibration...............................................................................................................40

5.6.2.6. Calibration adjustment........................................................................................................42

5.6.3. Settings.....................................................................................................................................43

5.6.3.1. Backlighting.........................................................................................................................43

5.6.3.2. Contrast..............................................................................................................................43

5.6.3.3. Clock...................................................................................................................................45

5.6.3.4. Printer.................................................................................................................................46

5.6.3.5. Language/Country..............................................................................................................47

5.6.3.6. Acoustic warning.................................................................................................................47

5.6.3.7. Soot (1/3)............................................................................................................................47

5.6.3.8. Standard.............................................................................................................................47

5.6.4. Control list.................................................................................................................................48

5.6.5. madur Service...........................................................................................................................48

5.7. Storing of results...............................................................................................................................49

5.7.1. Storing measurement reports...................................................................................................50

5.7.1.1. Report table........................................................................................................................51

5.7.1.2. Header (Notice) editing.......................................................................................................53

5.7.1.3. Erasing reports...................................................................................................................54

5.7.2. Continuous storing of results....................................................................................................54

5.7.2.1. Banks table.........................................................................................................................56

5.7.2.2. Erasing banks.....................................................................................................................56

5.7.3. Data-logger...............................................................................................................................57

5.8. Triple XL test......................................................................................................................................57

5.9. Printer................................................................................................................................................59

5.9.1. Printing the contents of a screen..............................................................................................59

5.9.2. Printing of all results..................................................................................................................59

6. Gas block diagram..................................................................................................................................61

7. Menu structure.........................................................................................................................................62

7.1. Structure of the main menu...............................................................................................................62

7.2. Structure of the menu STORE..........................................................................................................63

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1. INTRODUCTION

Congratulations on your purchase of the microprocessor-controlled flue gas ana-

lyser

GA-21 plus

It is a high quality instrument produced using the latest technical discoveries. The
GA-21 plus is easy to use. You also have the possibility of using the extra capabilities of
this analyser, of examining measurement results, checking service intervals and many
others. Please read the operating manual carefully. It contains valuable tips and informa­tion for problem-free operation. Regular maintenance will help to keep your analyser
ready for use at all times.

1.1. Use of this operating manual

Keep this manual with the analyser GA-21 plus, and take it with you when carry­ing out measurements. Here is a short description of the sections of this manual.

2. Maintenance

This section contains important information designed to keep your analyser work­ing and to save you time and trouble.

3. General information

This describes the most important characteristics of your new analyser.

4. Construction

A knowledge of the hardware of the analyser will help you to use the instrument
correctly and to avoid unnecessary down-time.

5. Operation

This section explains the use of the analyser with detailed descriptions of the vari­ous functions. It is important to read the sections 5.1 and 5.2 first. The other sections can
be read when required.

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2. MAINTENANCE

2.1. Gas sensors

The following points are important for maximising the operational life of the cells
and achieving measurements without errors:

 do not exceed the rated concentration;
 all the gas cells may react unpredictably to the presence of substances which are

not usually found in flue gases. For this reason, the analyser may not be cleaned
with chemical solvents. If organic solvents enter the gas chamber, the cells may
become unstable or even suffer permanent damage;

 some cells require the presence of a bias voltage when not in use. Do not allow

the battery to become fully discharged;

 do not switch the analyser off before the system is purged of remaining flue gas;
 store the analyser in a cool place to reduce the ageing of the cells.

2.2. Gas system

The gas system of the analyser is protected by a double in-line filter. The ele­ments should be changed when necessary. Check the condensate traps regularly and
empty them when needed.

2.3. Battery

The rechargeable battery used in the analyser is maintenance-free. An acoustic
warning signal is given when the voltage drops below 11 V. The GA-21 plus will switch off
automatically if the voltage should drop below 10.5 V. The analyser will operate for about
5 hours from the battery.

Warning:

Some parts of the analyser draw current even when the device is

switched off. If the analyser is not being used then the battery

should be charged fully at least once a month.

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2.4. Service intervals

The parameters of the electrochemical cells change with time, and therefore it is
necessary to carry out a service periodically. This service should include re-calibration of
the gas sensors using test gases. The recommended service interval is 800 operating
hours or 6 months, whichever comes first. The analyser is fitted with an operating hour
counter and automatically shows when a service is necessary.

The operating time and the number of hours until the next service are shown in

MENU->OPTIONS->madur SERVICE -> DEVICE INFO .

2.5. Errors during operation

The analyser checks all circuitry continuously. Should an error become evident,
then this is signalled acoustically and by the message "ERROR" on the screen. The error
can be found shown on the screen MENU->OP TIONS ->madur S ERVICE -> CONTROL

LIS T .

2.6. Switching off after use

The operating life of the electrochemical cells is dependent on the usage of the
instrument. The wear and tear on the cells is greater when the cell is exposed to the gas
for longer or the concentration is higher. The gas cell is hence "used up" during measure­ments.

Info:

For this reason, the analyser should not be switched off until all the

gas tubing has been completely cleared of flue gases and the gas

cells have been purged with fresh air for several minutes.

The GA-21 plus will not normally allow the instrument to be switched off if there
are still traces of flue gas in the system. The analyser will continue to operate until the sig­nals from the gas cells are nearly zero. This activity is shown by the message "VENTILA­TION REMOVE PROBE FROM FLUE".

The [OFF] key must be pressed twice to switch the instrument off completely.
Pressing the key once will put the analyser in the standby mode and the instrument will
remain in this mode until it is activated again by pressing "C" or switched off completely.

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Warning:

Certain conditions, such as strong electro-magnetic fields can

cause the analyser to become "hung-up". The only solution to this

problem is to switch the instrument off. It is, however, possible

that the analyser will no longer react to the keyboard and can not

be switched off.

Info:

Pressing the [OFF] key for a period of about three seconds will always

switch the analyser off.

3. GENERAL INFORMATION

The GA-21 plus is a multi-functional flue gas analyser. Electrochemical sensors
are used for the measurement of gas concentration. The instrument can be fitted with
between 2 and 4 of these sensors. All analysers are fitted with O2 and CO sensors, fur­ther gas cells must be chosen when the instrument is ordered.

The following description is based on an analyser containing 3 cells, the third one
being an NO sensor.

 Oxygen, O2
 Carbon monoxide CO
 Nitric oxide NO
 Carbon dioxide CO2
 Nitrogen oxides NOx

The first three gases (O2, CO, NO) are measured directly using the electrochem­ical cells. The remaining components are calculated. The concentrations of oxygen and
carbon dioxide are shown in percent. The concentrations of the remaining gases are
shown as follows:

 volume concentration in [ppm]
 absolute mass concentration in [mg/m3]
 mass concentration relative to the oxygen content in [mg/m3]

In addition, the air inlet or ambient temperature and flue gas temperature are
measured. Using the measured temperatures, gas concentrations and the known fuel

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parameters the analyser calculates a variety of combustion parameters such as Stack

Loss – SL, Efficiency - , Excess Air - , Loss through Incomplete Combustion – IL.

The GA-21 plus also measures differential pressure.. This can be used to meas­ure the draught or pressure in the flue gas channel. The instrument is also equipped for
the soot test according to Bacharach method.

The analyser is also fitted as a 3 channel data logger, capable of measuring
voltage or current together with temperature using thermocouples or thermistors.

The instrument can be used at a broad range of ambient temperatures (0 - 50°C).
It is fitted with a rechargeable battery making it independent of the mains power supply.

Hence, the GA-21 plus is ideally suited for all those involved in the construction,
maintenance and adjusting of heating systems.

The keyboard of the instrument can be wiped clean if necessary.

The GA-21 plus is controlled by a microprocessor. The easy-to-read LCD dis­play, the comprehensive keyboard and the built-in printer allow the operator to communic­ate with the instrument easily and to document the measurements on the spot. The EEP­ROM memory used in the GA-21 plus allows large quantities of data to be stored without
fear of data loss should the instrument be switched off or should the battery be accident­ally run down. The GA-21 plus comes complete with programmed data for the 18 most
common fuels. A further 10 fuels can be programmed by the operator to cover all eventu­alities.

The RS232C interface fitted to the GA-21 plus allows all stored data to be read
for later treatment or the instrument can be used on-line with the computer.

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4. CONSTRUCTION

4.1. Elements of gas circuit

4.1.1. Gas probe with in-line filter

The gas probe is used to extract the gas under investigation and to measure its
temperature. The gas probe consists of two parts, the probe pipe with thermocouple (1)
and the probe holder (2).

Picture 1. Gas probe with hose and in-line filter

The probe pipe is typically supplies in one of four standard lengths: 150 mm, 300
mm, 450mm, 750 mm, 1000mm and 1500 mm. As standard a Ni-CrNi thermocouple is
used. The probe pipe is fitted with an anchor cone to simplify fixation in the flue gas chan­nel.

The probe pipe is attached to the probe holder with a threaded connector.

The gas tubing in the GA-21 plus is protected from the dust and moisture present
in the flue gases by a filter (4). The filter elements (3) should be changed when dirty to
ensure a free flow of gas. The condensate should be removed from the condensate traps
when necessary.

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The plug (6) and hose quick coupler (7) are connected to the front plate of the
analyser.

4.1.2. Gas pump

The internal gas pump draws the gas into the GA-21 plus and passes it through
the gas chambers. The self-cleaning pump is a high quality item and is known to be ex­tremely reliable.

The gas cells operate best with a flow rate of 90 l/h, which is set at the factory
and is compensated automatically for flow restrictions or changes in battery voltage.

4.1.3. Gas chamber

The gas chamber can be fitted with minimum two and maximum six gas sensors.
Oxygen and carbon monoxide cells are standard equipment. The other sensors are
chosen when the instrument is ordered. The gas chamber of the GA-21 plus system is
characterised by minimal dead capacity, which leads to low inertia of the analyser indica­tions. In addition to the gas sensors, there is a temperature sensor placed in the chamber
for temperature compensation of the sensors.

4.2. Measurement system

4.2.1. Gas sensors

The oxygen concentration is measured using an electrochemical cell. The sensor
signal is directly proportional to the oxygen volume concentration. The oxygen sensor
needs no calibration with standard gases – it is fully calibrated during the initial calibration
when a point corresponding with the contents of oxygen in clean air (20.95%) is determ­ined.

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The toxic gases are also measured using electrochemical cells.

Table 1 presents all standard gas sensors available in GA-21 plus system.

Gas Cell type Range

O2 5FO 0-20.95 %

O2 MOX-1 0-100 %
CO 5F 0-20000 ppm
CO 5MF 0-10 %
CO A5F 2000 ppm
NO 5NF 0-5000 ppm

NO2 5ND 0-1000 ppm
SO2 5SF/F 0-5000 ppm

H2S 3HL/M 0-1000 ppm

H2 3HYT 0-2000 ppm

CL2 3CLH 0-250 ppm

HCl 3HL(s) 0-100 ppm

Table 1 Available gas cells and ranges

To guarantee long-lasting, trouble-free function of electrochemical sensors the fol-

lowing points are important:

 the stated maximum measuring range of the sensor should not be ex-

ceeded.

 all of the gas sensors can react unpredictably to certain chemicals

which are not typical for combustion gas composition. For this
reason, it is absolutely forbidden to wash the parts of the gas line with
chemical solvents. The vapours from such solvents can get inside the
gas chamber and result in destabilisation or even permanent damage
of the gas sensors.

 the gas sensors are working even when the analyser is switched off -

so the battery should never be disconnected or completely dis­charged.

 the analyser should not be switched off before all the flue gases have

been removed from the analyser's gas circuit.

 the sensor chamber must be kept dry.
 the switched off analyser should be kept in a cool place, which in-

creases the lifetime of the gas sensors.

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4.2.2. Ambient temperature sensor

The ambient temperature is measured by the analyser for use in some of the cal­culations carried out, such as Stack Loss. This can be carried out either by the temperat­ure compensation sensor built into the plug of the probe holder (INT) or the external con­nector T3 (EXT). The temperature sensor is chosen under the suboption:

OPTIONS → SENSORS → ANALOGUE INPUTS.

4.2.3. Flue gas temperature sensor

The flue gas temperature sensor is situated in the gas probe pipe and plugged
into the PROBE socket on the front panel of the analyser. This sensor is a NiCr-Ni ther-

mocouple in the standard probe version. The range of such a thermocouple is 50-800oC
in the standard version (1100°C available optionally). A special gas probe with PtRh-Pt

thermocouple can also be used, with a range up to 1600oC. Proper flue gas temperature
measurement is the most important factor for correct calculation of the chimney loss and
other heat engineering results.

4.2.4. Gas chamber temperature sensor

To compensate for temperature drift of the gas cells, the temperature of the gas
chamber is constantly monitored.

4.2.5. Differential pressure sensor

The GA-21 plus is fitted with a precise semiconductor differential pressure
sensor. Stubs marked +/- PRESSURE situated on the left side of the front panel are used
to measure pressure. Negative pressure in flue gas channel (chimney draught) can be
measured with the one stub only; differential pressure measurement is possible using
both stubs. The measuring range of the pressure sensor is +/- 25 hPa.

4.2.6. Analogue inputs

The three analogue inputs installed can be used to measure voltage or current on
two channels (U and I), temperature using a thermocouple (T1 EXT) and temperature us­ing a thermistor (T3 EXT). The values measured can be viewed on the screen or stored in
the EEPROM memory.

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Current and voltage inputs – top view (outputs - optional)

1 – GND
2 – I1 in
3 – U1 in
4 – I1 out GND (optional)
5 – I1 out (0/4-20mA, optional)

Parameter U I

Range -10V to +10V -10mA to +10mA

Input resistance 100kΩ 100Ω

Resolution 10mV 10µA

Temperature input – top view

1 – PT3 (Thermistor 1 +)
2 – TH1 (Thermocouple 1 +)
3 – GND (-)

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Parameter Thermocouple Thermistor

Range Ni-CrNi: 1 – 1300°C

Pt-RhPt: 0 – 1600°C

Fe-CuNi: 0 – 700°C

Pt100: 0 – 200°C
Pt500: 0 – 500°C

Resolution 1°C 1°C

4.3. Data input/output system

4.3.1. Keyboard

A film keyboard is used in the GA-21 plus analyser which is durable, washable
and highly resistant to external agents. The keys are modern membrane keys with per­ceptible stroke.

Each press of a key is accompanied by an acoustic signal. The keyboard is
shown in picture B (page 14) and consists of the following elements:

PROBE - Socket for the electrical connection of the probe holder

GAS -Connector for the gas hose

PRESSURE +,- -Connectors for the differential pressure sensor

RS 232 C -Socket for the RS232C cable

TEMP. 1 -Socket for the temperature channels 1 & 2

U/I 1 -Socket for the current/voltage channels

Function keys -

Arrow keys -

Printer keys -

ON/OFF keys -

Numerals - to

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Picture 2. Front elevation picture

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4.3.2. Display

The GA-21 plus has an LCD display with graphic capabilities. To improve the
read-out quality, contrast regulation for the display and backlighting are used. Measure­ment results, calculation results, diagrams, text information, menu options and others ap­pears on the display.

4.3.3. Printer

The GA-21 plus is fitted with an EPSON dot matrix printer capable of printing the
data as graphic or in the form of tables. All the screens seen on the analyser may be prin­ted.

Printing speed is about 2.5 lines per second. The printer uses normal paper, 57
mm wide.

4.3.4. Interface RS232C

The GA-21 plus is fitted with a serial RS232C interface. The socket is mounted
on the front of the instrument and marked RS232C. The interface allows the GA-21 plus
to communicate with a PC and the software madCom is available for carrying out extens­ive analysis of the stored results.

Top view

1 – +15V out
2 – RxD
3 – GND
4 – TxD

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4.3.5. Power supply

The GA-21 plus can be used with mains power supply or be operated from the
internal battery. A soot test can only be carried out when the mains supply is connected,
otherwise the heating of the probe holder will not function. The mains cable is attached to
the socket on the left of the keyboard. Switching the mains supply on or off when the in­strument is in operation is not recommended. The analyser switches automatically to the
internal battery when the mains supply is disconnected. The LED on the front panel
shows which power supply is in use.

Red -analyser is switched on and supplied from the battery. Mains supply

not present.

Green -analyser switched off and mains supply present. The battery is char-

ging.

Orange -analyser switched on and mains supply present. The battery is char-

ging.

The maintenance-free 12 V battery has a capacity of 2 Ah. A fully charged battery
will power the instrument for about five hours.

When the battery voltage drops below 11 V, three acoustic warnings and blinking
of the LED on the front panel will appear. The message ERROR appears at the top of the
screen and the CONTROL LIST contains the line BATT LOW.

The instrument switches off automatically if the battery voltage drops below

10.5V.

The battery is charged by connecting the instrument to the mains power supply.

The state of charge can be seen during the initial calibration or read from the
screen DEVICE INFO:

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5. OPERATION

5.1. Use of the keyboard

5.1.1. Description of the keys

- Switches to the STORE menu

- Switches to the first results screen. From the current
results, the use of this key switches between MEAS­URE and HOLD.

- Switches to the MAIN MENU

- Confirms entries and switches options

to - Alphanumeric keyboard for entering data and for fast

movement between MENU options

- Decimal point when entering data. If used when the
screen is showing RESULTS, this key switches the
zoom function on or off.

- starts a print-out

- moves the paper forward one line

- switches the analyser on

- switches the analyser to stand-by or off

- moves one step backwards in the menu

- moves one step forward in the menu or, during edit­ing, moves the cursor one space to the right

and - move the cursor vertically in the menu

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5.1.2. Selecting menu options

The menu structure is shown at the end of the manual. The various displayed

menus are leading the user through the structure.

The following picture shows an screen, which explains the different types of exist-

ing lines.

Here is an explanation of the movement between the various menu options:

and - move the cursor vertically in the menu

- if the cursor is on the left side of the Title line, the
key moves one step backwards in the menu

- if the cursor is on the right side of the Option line or
the Title line, the key leads to the displayed Option.

- executes the displayed function (starts data storage
for example ), in the Command line starts or ends the
respective edit function (setting the average time for
example ) in the Data line switches (i.e. YES/NO) in
the Switch line

to - for fast movement between MENU options

If a displayed line carries a function, then there will be a number (1 to 9) on the
left side of the line. Press the number of the option you want to select, and the cursor will
"jump" to the selected line. If number 4 is pressed in the above demo screen the beam
would move to BOILER DATA.

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5.1.3. Entering numbers

Numbers are edited as follows:

- digital keys enter corresponding numbers

- move the cursor within the line

- erases whole number (zero on each position)

- confirms and ends the entry

5.1.4. Editing text

Text is edited as follows:

- switches the keyboard into either digital or alpha
betical mode. When in digital mode the cursor has a
block form on the screen, in the alphabetical mode
it has the shape of an underlining

- move the cursor within the line

- erases the whole text line

- the alphanumeric keys enter numbers in digital
mode or letters in alphabetical mode. Each key has
a three letter designation. The first press enters the
first letter, the next presses the second and the third
letter. Key presses in alphabetical mode does not
move the cursor.

- (SPACE) prints 0 number in digital and the space
character in alphabetical mode. The space moves
all the next characters one position to the right.

- (DEL) erases the character above cursor position.
This moves all the following characters one position
to the left.

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- ends the entering of a text (if only one line is edited

- e.g. the name of a fuel) or moves the cursor down
to the next line (if there are several lines in the ed
ited text - e.g. the report header)

- end the editing of a header or footer - it enables the
storage of edited text. If you do not need to store
the contents of header or footer you should leave
the screen by pressing the MENU key.

5.2. Basic operating instructions

5.2.1. Setting-up the analyser

Connect the components of the analyser system:

- Attach the hose to the connector GAS. The plug from the probe holder
connects to the socket PROBE.

- Attach the outlet hose from the filter to the connector INLET

- Ensure that the gas flow from the base of the analyser is free of ob
structions.

5.2.2. Switching on

Before use, the condition of the analyser should be checked:

-Check the filter elements. Clean or replace as necessary.

-Check the state of charge of the battery if the analyser is to be operated
from the internal battery. This is carried out by switching on and reading
the battery voltage or charge from the initial screen, or from the screen
MENU/OPTIONS/DEVICE INFO.

5.2.3. Switching off / standby

Pressing the key [OFF] once will switch the analyser to the STANDBY mode.

In STANDBY mode the power consumption is drastically reduced. Amongst oth­ers the pump and the backlight are switched off. Only the sensors remain supplied to be
ready to operate immediately after the instrument is switched on again.

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The analyser does not switch to STANDBY mode if [OFF] is pressed in case:

-the key is being pressed during Initial Calibration. In that case the instru
ment realises the action, but will switch to STANDBY only after the cal
ibration is finished.

-the key is being pressed while the is still a high gas concentration detec
ted in the gas chamber. In this case the instrument will automatically
switch to FLOODING WITH AMBIENT AIR mode and switch to
STANDBY mode later on.

The following screen is shown in the STANDBY mode.

By pressing [OFF] the instrument can be switched off completely. If [C] is
pressed the instrument switches ON again. If the instrument is in STANDBY mode for
more than 8.5 hours it switches off automatically. It is highly recommended to carry out a

calibration of the oxygen sensor when re-activating the instrument.

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5.2.4. Initial calibration

After the instrument is switched on it carries out an initial calibration for 2 minutes.

Warning: Make sure the probe is not in the stack during the initial calib

ration

Initial calibration is of basic importance for measurement correctness and it must
not be interrupted before it is finished automatically.

During this time the Oxygen sensor is calibrated to 20,95% in ambient air, and
the other sensors (CO, NO,...) will be zeroed.

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5.2.5. Measurement parameters

Directly after the calibration is finished the option PARAMETER is displayed for
control reasons or in case changes need to be done. Usually the option is selected as fol­lows:

- selects the MENU screen

and - move the cursor to the PARAMETER option

- select the option. The following screen will appear:

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5.2.5.1. Fuel selection

This option enables the selection of a fuel (if necessary), or the programming of a
customised fuel.

From PARAMETER you move to the option as follows:

and - move the cursor to FUEL

- choose SELECT FUEL

and - move the cursor to the desired fuel

- confirm the selection - an asterix (*) will apear
on the left side

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Each fuel of this screen is defined through various parameters. To view them pro-

ceed as follows:

and - move the cursor to the desired fuel

- displays the fuel parameters , or gives the opor
tunity to enter fuel data for the programmable fuels.

- back to option FUEL

The following screen appears.

The already defined fuels can only be viewed. For the user definable fuels all

parameters can be programmed.

The variables are as follows:

• 0000000000- Name of the fuel

• DP-

• CO2max - the maximum concentration of CO2 (for complete combustion,

O2=0 %)

• A1, B - factors for Siegert's formula

• ALPHA - fuel specific parameter

• O2R - reference oxygen

• Vgd - volume of the flue gas at perfect combustion of the fuel

• HV - Heating value of the fuel

• UNITS - unit in which the fuel is measured

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5.2.5.2. Averaging time

To select the average time proceed as follows:

and - move the cursor to AVERAG. TIME

- select Average Time edition

to - select the time (1 to 60 )

- confirm the number

and - select min or sec

- confirm the selection

5.2.5.3. Reference oxygen parameters (O2R)

To select the reference oxygen proceed as follows:

and - move the cursor to O2R

- switches between a pre-programmed standard
value <NORM> and a free programmable one,
called manual value.

to - if "manual" was selected, a number from 1 to 20

can be entered

- confirms and ends editing

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5.2.5.4. Boiler parameters

This option enables the user to have relevant boiler parameters printed on the

Protocol printout for exact documentation.

and - move the cursor to BOILER-PARAMETER

- select with YES/NO whether or not the Boiler Para­meters shall appear on the printout, respectively be­ing stored in a Protocol

- if YES was selected, this key moves to the Boiler
Parameter menu. The boiler parameters can be
entered in the screen shown below:

• Boiler power

• Boiler consumption

• Boiler temperature

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5.3. Displaying the measurement results

Select the measurement screen by pressing DATA. The measurement results are

displayed on three screens, either as current values or as averaged values.

5.3.1. Current values

- select the first screen

and - move backward or forward to select a screen

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- switches between AVERAGED VALUES and CUR-

RENT VALUES

- switches On/Off the HOLD function ("freezing" the
current values )

5.3.2. Averaged values

Select desired averaging time as described in section 5.2.5.2.

- select the screen. The title line has to read AVER-

AGED VALUES

and - backward or forward to select one of four

screens

- switches between AVERAGED VALUES and CUR-

RENT VALUES

- the display on the AVERAGED VALUE screen gets
"synchronised" (a row of strokes appears instead of
the values) and a new averaging
session starts. The meas ured results
are displayed after the whole cycle
is finished.

- switches On/Off the HOLD function ("freezing" the
current values)

Warning:

If a continuous storage recording is taking place the analyser won't syn-

chronise the averaging process (not to interfere with the continuity of stor-

age )

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5.3.3. The averaging process

The analyser is capable to display all results, measured or calculated, either as
current value or as averaged value. The averaging time can be selected in a range of 10
seconds to 60 minutes. If a time of 1 min was set, the averaged results over that time
would be shown on the display. During the start of the averaging process a row of strokes
appears on the screen, since there are no results to display.

If measurement parameters are changed during the averaging process, the aver­aging cycle has to be re-started.

In case the data storage is activated it is stopped as well.

The following incidents cause an interruption of the averaging cycle.

• change of the averaging time

• change of the reference oxygen

• change of the fuel

• switching the instrument to the STANDBY mode

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5.4. Pressure/Draft measurements

It is possible to measure differential pressure with the GA-21 plus. To do so the
stubs PRESSURE (-) and (+) on the front plate are used. The measurement is performed
as follows:

- select the main MENU

and - move the cursor to PRESSURE

- select the option. The following screen appears

The current pressure and gas temperature are displayed on the screen. The last
line shows the command ZEROING. By pressing this key the sensor is set to zero, e.g.
the current value will be taken as zero value..

Please be aware that the sensor has to be zeroed before the measurement.

- ZEROING the sensor

Connect end of the sample hose to the PRESSURE(+) stub. The screen will dis­play the measured pressure and the measured gas temperature.

- leaves the option. The displayed value will be stored
until a new one is stored or either a printout of the
measured values is performed or they are stored as
a report.

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5.5. Soot (smoke) Measurement

To perform a soot test it is essential to prevent the flue gas from condensing on
the filter. Therefore it is necessary to use a heated probe holder. It is only possible to per­form a soot test if the instrument is connected to the mains.

The soot test is done by means of the Bacharach comparison method.

- select the main MENU

and - move the cursor to SOOT TEST

- select the option, the pump is switched off and the
following screen appears:

Insert the soot filter in the slit of the heated probe holder, and place the probe in

the stack.

- starts the soot measurement. The pump is switched
on and sucks in 60 s (according to. TÜV) the re­quired volume of 1.63 +/-0.07 l

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- stops the soot test

After the soot test the filter is compared with a scale, and the evaluated soot num-

ber is entered.

to - enter the detected soot number

- confirm the soot number

The stored soot number remains stored until a new one is entered, or either a

printout of the measured values is performed, or they are stored in a report.

5.6. Options

The OPTIONS can be reached from the MENU as follows:

and - move the cursor to OPTIONS

- select option. The following screen appears

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5.6.1. Device info

and - move the cursor to DEVICE INFO

- select option

The DEVICE INFO screen shows the serial no. of the instrument, the date of the
last service, the operating time, the time until the next service, the speed of the sucked
flue gas , the battery charge, the battery capacity and whether or not the communication
with the madCom PC software is locked.

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5.6.2. Sensors

Select the option SENSORS from the screen OPTIONS as follows:

and - move the cursor to SENSORS

- select the option. The following screen appears

5.6.2.1. Sensor CO (only in dual CO sensor configuration)

In dual CO sensor configuration there is possibility to select working mode:

-Auto – This mode is designed to protect low range CO sensor. Measurement
results collected using low concentration CO sensor. When the meas­ured gas concentration exceeds value inserted in CO C. range then
the purging pump starts flushing the low concentration CO sensor with
ambient air for its protection. Result are from this point collected using
high concentration CO sensor. When the gas concentration drops be­low value inserted in CO C. range then the pugging pump stops and
the measurements are again collected using low concentration CO
sensor.

-Hi – In this mode purging pump is always on and results are always collec­ted using high concentration CO sensor.

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5.6.2.2. CO range

If the concentration of CO in the gas stream exceeds the limit set here, then the

cell is automatically purged with fresh air. This limit can be altered as follows:

and - move cursor to the line CO RANGE

- start editing of the value

to - enter a number between 0 and 20000 ppm

- close the option

5.6.2.3. O2 cell calibration

To increase the accuracy of the O2 sensor during measurements over a longer
period of time the GA-21 plus has the capability of calibrating the sensor with ambient
air.

Take the probe out of the stack !

and - move the cursor to O2 cell calibration

- select the option. The following screen appears

- confirms the calibration

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5.6.2.4. External channels

Get from the screen SENSORS to the option EXTERNAL CHANNELS as fol­lows:

and - move the cursor to EXTERNAL CHANNELS

- select option

and - move the cursor to the line to be changed

- change the setting:

TH GAS - Gas temperature sensor – default setting: NiCr-Ni. For special

applications (temperatures up to +1600°C) the setting can be
changed to PtRh-Pt thermocouple. Of course that would need
the use of the respective thermocouple as well.

Pt AMB - Ambient temperature sensor - default setting: Pt 500. The

ambient temperature can either be measured with an internal
sensor placed in the probe plug (Pt500), or with an external
sensor (Pt500), connected to the TEMP (T3 EXT.) socket.

T1/T2 EXT - External thermocouple - Select the desired temperature

sensor. The T1 EXT input can be defined as a Ni-CrNi, Pt-RhPt
or Fe-CuNi thermocouple.

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T3/T4 EXT - External resistance thermometer - Select the desired temper-

ature sensor. The input T3 EXT can be defined as a Pt100,
Pt500 or KTY-2k thermistor.

U/I1 EXT - External Voltage/Current input - Select the desired input sig-

nal . The socket U/I1 can be used to measure either current (0­10 mA) or voltage (-10V - +10V).

U/I2 EXT - External Voltage/Current input – second current or voltage in-

put

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5.6.2.5. Sensor calibration

Except for O2 every electrochemical sensor needs to be calibrated with calibra­tion gas. To calibrate the sensors they are fed one by one with calibration gas of a known
concentration. After a few minutes the sensor supplies a stabilised signal which can be
stored as calibration value. The order of calibration does not effect the calibration.

Warning:

Any calibration screen value change is followed by loss of the original cal-

ibration settings. Thus the CALIBRATION option should be selected only when it is

to be carried out.

The standard gas concentration should be similar to that usually met during
measurement and it should not be less than 10% of the required measuring range of a
given sensor

The time the sensor is fed with standard gas should not be less than 4 min. After
each calibration the sensors should be flooded with ambient air for at least 15 minutes.

Calibration procedure:

and - move the cursor to CALIBRATION W. GAS

- select the option

- carry on with the calibration

- abort the calibration, move back to SENSORS

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and - move the cursor to the sensor to be calibrated

- select the gas type

Calibration screen will appear:

All currently installed electrochemical sensors are visible in this screen

The individual rows have the following meanings:

Cell – Sensor type

Signal – Current value of sensor's signal

Stored – Value of stored signal

- in the GAS [ppm] line, starts editing of the standard
gas concentration

to - enter the concentration of the standard gas [ppm] in

the line GAS

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- in the GAS line. Confirm standard gas editing. Sup­ply the instrument with standard gas for about 4 min.

- in the STORE line, as soon as the value has stabil­ised, stores the measured value as calibration value.
Disconnect the standard gas and flood the instru­ment for at least 15 min with ambient air.

- return to select the next gas, or end the calibration

5.6.2.6. Calibration adjustment

Calibration adjustment is a new feature (introduced in firmware version 2.07). Al­lows to perform a quick correction to a factory calibration using one calibration mixture
(mixture of gases in N2 balance).

Calibration adjustment does not substitute factory calibration with a single gas in
N2 balance. I .e. calibration adjustment cannot create matrix of cross-sensitity signals –
this is created only during standard calibration.

- means that correction for a selected gas is applied.

If all sensor are unmarked: , it means no adjustment to factory calibration is ap­plied.

To perform calibration adjustment:

Enter the concentration for each gas present in mixture. If any of listed gas is not
present in mixture set its concentration to 0 → analyser will not include this sensor in ad­justment.

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Apply reference mixture for few minutes and allow the signals to stabilise.

Finish the adjustment by pressing * ADJUST * button.

Adjustment is remembered, even after powering ON/OFF the analyser! To re­move this calibration adjustment, one need to manually perform REMOVE ADJUST-

MENT.

5.6.3. Settings

This option allows the user to adjust some of the standard settings.

and - move the cursor to the option SETTINGS

- select the option

5.6.3.1. Backlighting

- pressing the key switches the BACKLIGHTING on
and off

5.6.3.2. Contrast

and - move the cursor to CONTRAST

- select option

Follow the explanations on the screen to adjust the contrast

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5.6.3.3. Clock

This option allows the internal clock to be adjusted.

and - move the cursor to CLOCK

- select option

and - move the cursor to desired line

- opens editing

to - set date and time. They are entered in the sequence

TIME - HH:MM.SS and DATE as given by the format
line below.

- confirms settings

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5.6.3.4. Printer

This option allows the printer (printout) settings to be defined.

and - move the cursor to PRINTER SETTINGS

- select option

SHORTFORM - switches between YES/NO. If the option is activ-

ated, then a print-out of the current values will
show only the volume concentrations of the
gases, not the mass concentrations in mg/m³. A
stored report will still have all the information as
usual.

AUTO PRINTING - switches between YES/NO. If the option is activ-

ated, automatic printouts will be carried out ac­cording to the programmed average time,
provided the time is not less than 2 min. If the av­erage time is shorter than 2 min. only one prin­tout will be performed.

No OF COPIES - switches between 1/2/3.
FOOTER No - the instrument can store up to 50 footers. Num-

ber one is already stored and can not be
changed. If address 0 is selected, no footer will
be on the printout. The footers 2 to 50 are freely
programmable.

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5.6.3.5. Language/Country

The instrument enables the user to select between languages.

and - move the cursor to LANGUAGE

- confirms the selection

and - select language

- confirms the language

5.6.3.6. Acoustic warning

- enables/deisables acoustic warning

5.6.3.7. Soot (1/3)

5.6.3.8. Standard

- sets the instrument to default settings

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5.6.4. Control list

The option CONTROL LIST displays a similar list to the one above. The list

shows which subassembly functions correctly (OK), or which is defective (*E*).

and - move the cursor to CONTROL LIST

- select option

5.6.5. madur Service

This option is for service engineers only. A code is needed to enter the menu -

exit with [MENU] key.

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5.7. Storing of results

Since the measured results can be stored in the EEPROM memory, it is possible
to read them out later for treatment using the madCom software. Data can be stored in
two separate forms. Up to 30 measurement reports and up to 10 banks from continuous
measurements containing a total of 1024 sets of results. Using an averaging time of 30
minutes, this would allow the results of over 21 days of measurements to be stored
(please be aware that for measuring sessions of that length a proper gas conditioning
system is absolutely necessary)

- selects the menu STORE

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5.7.1. Storing measurement reports

The measurement report contains all the results obtained in a single measure­ment. It contains either current or averaged values and other user-defined factors such as
fuel, footer, header etc. If the report should contain soot measurement results or pressure
data, then these measurements must be carried out before storing the report. The report
will contain either the current or the averaged results depending on which screen was vis­ible when the storing process was started.

Store REPORTS as follows

- the measured values are displayed. Do you want to
print the displayed valuesproceed as follows

- select option. The measured values are stored in a
buffer memory

and - move the cursor to REPORTS

- select option REPORTS

and - move the cursor to SAVE REPORT No. XX

- the "buffered" data are stored in a Report with the
displayed number.

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5.7.1.1. Report table

This option allows one to view, print and erase Report contents.

and - move the cursor to REPORTS TABLE

- select option

Reports without [♦] are empty.

- erases the selected Reports

- shows the selected Reports, the following screen
REPORT NO.: XX is opened

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5.7.1.2. Header (Notice) editing

This option allows to edit a notice which can be stored and printed with a Report.

The HEADER may have 4 lines of 20 characters.

Measurement site and/or short description of the site are commonly stored in

such notes.

and - move the cursor to HEADER EDITING

- select option

The pictures show screens without text. The screen appears as it was when the

report was stored. How the text should be edited is described in section 5 .1.4 .

This screen can be left at any time using [MENU] and [DATA].

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5.7.1.3. Erasing reports

All protocols can be erased in that option.

and - move the cursor to DELETE ALL REPORTS

- select option

- leaves the screen without erasing the Reports

- erases all reports

5.7.2. Continuous storing of results

This type of storing involves the continuous storing of a set of up to 10 measure­ment results (ONE BLOCK) during a measurement session. The EEPROM can store up
to a total of 1024 blocks freely dividable between 10 measuring sessions. These 10 sets
of results are known as BANKS. The size of a single bank is only limited by the free
memory available. Each bank also contains all necessary information about the measure­ment (fuel, time, O2R, averaging time etc.). All the results stored are average results for
the time set. If the analyser is switched off, and under certain circumstances, the storing
of averaged results will stop automatically.

This is signalled by a single long warning tone.

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Starting the continuous storing of results ( in Banks )

- call the STORE menu

check whether enough free memory is available for the measurement. If not, one
or more banks must be erased. The option DELETE ALL BANKS can be used.

and - move the cursor to the option BANKS

- open the option BANKS

and - move the cursor to the line STORAGE

Set or check the averaging time.

- start the storing, the word ACTIVE appears

- the measured/calculated values are shown, storage
is active

Stopping the continuous storing of results

- call the STORE menu

and - move the cursor to the option BANKS

- open the option BANKS

and - move the cursor to the line STORE

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- storage is stopped, the word ACTIVE disappears

5.7.2.1. Banks table

The option BANKS TABLE provides information about the stored Banks.

and - move the cursor to the option BANKS TABLE

- select the option BANKS TABLE.

The last bank can be erased in the BANKS TABLE screen (the Bank must not be

active)

and - move the cursor to the last stored Bank

- erase bank

5.7.2.2. Erasing banks

The option DELETE ALL BANKS allows to erase all Banks.

and - move the cursor to DELETE ALL BANKS

- select the option

- leaves the screen without erasing BANKS

- erases all BANKS

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5.7.3. Data-logger

GA-21plus analyser can be optionally equipped with data-logger. Such device
has additional microSD card slot, located beneath the printer cover. Data-lgger options
are available from Store menu:

To use data-loger, insert SD card to the slot and, if necessary, format it from analyser’s
menu. Then thick Recording option to start collecting measurements to csv file (comma
separated) on SD card.

5.8. Triple XL test

for

2 seconds.

Before executing the test, set necessary parameters:

1. Header (Notice) editing

2. Fuel selection

3. Averaging time

4. Reference oxygen parameters (O2R)

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5. Boiler parameters
When all is set, execute 3-XL by pressing ***** START **** - analyser will perform test ac­cording to the set averaging time. Each test will start immediately after previous one has
ended. Currently performed test is indicated with its number in top left corner. Results
presented on screen are for the previous period, i.e. during the first test, instead of results
‘----’ are presented. During the second test, results from the first period are presented.
During the third test, results from the second test are presented:

3-XL test is stored along with reports. 3-XL test occupy memory of 2 reports, and

are marked in Report table with +:

Reports from 3XL test contains 4 pages:

Average from all 3 tests Average from the 1st test Average from the 2nd test Average from the 3rd test

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5.9. Printer

5.9.1. Printing the contents of a screen

This is not possible for the screen (D1). A screen may not be printed whilst data is

being entered using the alphanumeric keyboard until this activity has been ended.

- prints the contents of a screen

5.9.2. Printing of all results

- open the first results screen (D1)

- start a print-out containing all measured results

If the current values are displayed they will be printed; if the averaged values are

displayed then these will be printed.

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6. GAS BLOCK DIAGRAM

1. Gas inlet

2. Filter

3. Main gas pump

4. Flow control sensor

5. Pressure sensor

6. Electrochemical cells in the main gas channel

7. Check valve

8. Purging pump

9. Electrochemical cell in the secondary gas channel

10. Gas outlet 1

11. Gas outlet 2

12. Differential pressure inlets for the duct's flow velocity measurement

13. Second pressure sensor

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7. MENU STRUCTURE

7.1. Structure of the main menu

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MAIN

Parameter Fuel selection Choose fuel View/define

Average time

O2R

Boiler data

Pressure Pressure

Soot test Soot test

Options Device info. View data

Sensors CO range

O2 cell calibr. Calibrate

External channels Choose input TH Gas

PT Amb.

T1ext. / T3ext.

U/I1

Calibration w. gas Choose cell Calibrate

CO2 zero

Settings Backlighting

Contrast Set contrast

Clock Set date/time

Printer settings Shortform

Automatic printing

No. of copies

Choose footer

Language/country Language

Standard

Control list

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7.2. Structure of the menu STORE

STORE

Reports Save Report No.

Reports Table View Report

Header Editing Edit

Banks Activate/Lock

List of Banks View List

Delete All Reports Erase All

Delete All Banks Erase All

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