XS Instruments OXY 7 Vio User manual

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Rev 1.0 11/02/2020
EN
OXY 7 Vio
INSTRUCTIONS MANUAL
%O
2
– mg/l – mbar - Temp

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Rev 1.0 11/02/2020
EN

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Index
.................................................................................................................................................................1
Introduction .............................................................................................................................................5
Safety information ...................................................................................................................................6
•Definitions of warning words and symbols .........................................................................................6
•Reporting terms: .................................................................................................................................6
•Additional documents for safety.........................................................................................................7
•Use according to destination...............................................................................................................7
•Basic requirements for a safe use .......................................................................................................7
•Unauthorized use ................................................................................................................................7
•Device maintenance............................................................................................................................7
•Responsibility of the owner of the instrument ...................................................................................8
Instrumental features ..............................................................................................................................8
•Parameters ..........................................................................................................................................8
•Datasheet ............................................................................................................................................8
Instrument description ............................................................................................................................9
•Display .................................................................................................................................................9
•Keyboard ...........................................................................................................................................10
•LED.....................................................................................................................................................10
Installation .............................................................................................................................................10
•Supplied components........................................................................................................................10
•Start-up..............................................................................................................................................10
•Turning on and off .............................................................................................................................11
•Replacement of batteries..................................................................................................................11
•Instrument transportation ................................................................................................................11
•Key functions.....................................................................................................................................11
•Inputs / Outputs connections ...........................................................................................................12
READ THE MANUAL BEFORE PROCEEDING TO CONNECT THE PROBES OR PERIPHERALS ........................12
•Symbols and icons on the display .....................................................................................................13
Operation of the device.........................................................................................................................13
Setup Menu ...................................................................................................................................14
•Setup menu structure ......................................................................................................................15
Temperature measurement ATC – MTC ....................................................................................15
%O2 Parameter ..............................................................................................................................15
•O2parameter Setup ..........................................................................................................................15
•Composition of the Setup menu for O2 Parameter...........................................................................16
•Information about sensor DO 7.........................................................................................................17
•Sensing element................................................................................................................................17

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•Membrane.........................................................................................................................................17
•Electrolyte .........................................................................................................................................17
•Polarization time ...............................................................................................................................17
•New sensor with new instrument .....................................................................................................18
•Probe storage ....................................................................................................................................18
•Not using the sensor for long period of time: over one month ........................................................18
•Oxygen sensor calibration ...............................................................................................................18
•Calibration in air at 100% ..................................................................................................................18
•Calibration with zero oxygen standard .............................................................................................19
•Calibration range ...............................................................................................................................20
•Errors during calibration ..................................................................................................................20
Dissolved oxygen measurement ..................................................................................................20
•Before starting...................................................................................................................................20
•Measure Mode..................................................................................................................................20
•Performing the measurement...........................................................................................................21
•Barometric pressure compensation ..................................................................................................21
Probe DO 7 maintenance .................................................................................................................21
•Electrolyte replacement....................................................................................................................21
•Maintenance of the anode and the cathode ....................................................................................22
•Replacement of the membrane ........................................................................................................22
Instrument Setup Menu .................................................................................................................22
•Composition of the setup menu for Setting menu ...........................................................................22
Warranty ...........................................................................................................................................24
•Warranty period and limitations .......................................................................................................24
Disposal of electrical devices ............................................................................................................24
XS Instruments
Via della Meccanica n.25
41012 Carpi (MO) ITALY
Tel.[phone] Fax [phone]
www.xsinstruments.com

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Introduction
XS Instruments, globally recognized as a leading brand in the field of electrochemical measurements, has
developed this new line of portable instruments completely produced in Italy, finding the perfect balance
between performance, attractive design and ease of use.
The robustness and integrity of the case, the integrated brightness sensor and the practical carrying case
make this instrument ideal for measurements directly in the field.
Thanks to the triple power supply and the ability to manually change the contrast and brightness of the
display, this instrument is also suitable for use in the laboratory.
The innovative high definition colour LCD display shows all the necessary information, such as the
measurement, the temperature, the buffers used for the last calibration.
Everyone can use these tools thanks to the instructions that appear directly on the display. The calibration
is guided step by step and the instrument configuration menu is easy to consult. In addition, a LED
indicates the status of the system to the user.
Up to 2 calibration points can be carried out for the dissolved oxygen measurement with automatic
recognition of values.
It is possible to consult the calibration data anytime and the representation makes the calibration process
more efficient, through the icons of the buffers used.

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Safety information
•Definitions of warning words and symbols
This manual contains extremely important safety information, in order to avoid personal injury, damage to
the instrument, malfunctions or incorrect results due to failure to comply with them. Read entirely and
carefully this manual and be sure to familiarize with the tool before starting to work with it.
This manual must be kept near to the instrument, so that the operator can consult it easily, if necessary.
Safety provisions are indicated with warning terms or symbols.
•Reporting terms:
ATTENTION for a medium-risk hazardous situation, which could lead to serious injury or death, if
not avoided.
ATTENTION for a dangerous situation with reduced risk which can cause material damage, data loss
or minor or medium-sized accidents, if not avoided.
WARNING for important information about the product
NOTE for useful information about the product
Warning symbols:
Attention
This symbol indicates a potential risk and warns you to proceed with
caution.
Attention
The instrument must be used following the indications of the reference
manual. Read the instructions carefully.
Advice
This symbol draws attention to possible damage to the instrument or
instrumental parts.
Note
This symbol highlights further information and tips.
Attention
This symbol draws attention to a possible danger from electric current.

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•Additional documents for safety
The following documents can provide the operator with additional information to work with the measuring
system safely:
•operating manual for electrochemical sensors;
•safety data sheets for buffer solutions and other maintenance solutions (e.g. storage);
•specific notes on product safety.
•Use according to destination
This instrument is designed exclusively for electrochemical measurements both in the laboratory and
directly in the field.
Pay attention to the technical specifications shown in the INSTRUMENT FEATURES / TECHNICAL DATA table;
any other use is to be considered unauthorized.
This instrument has been manufactured and tested in compliance with EN 61010-1 safety standards relating
to electronic instruments and has left the factory in perfect technical and safety conditions (see test report
in each package).
The regular functionality of the device and the operator safety are guaranteed only if all the normal
laboratory safety standards are respected and if all the specific safety measures described in this manual
are observed.
•Basic requirements for a safe use
The regular functionality of the device and the operator safety are guaranteed only if all the following
indications are respected:
•the instrument can be used in accordance with the specifications mentioned above only;
•use the supplied power supply only. If you need to replace the power supply, contact your local
distributor;
•the instrument must operate exclusively in the environmental conditions indicated in this manual;
no part of the instrument can be opened by the user.
Do this only if explicitly authorized by the manufacturer.
•Unauthorized use
The instrument must not run, if:
•it is visibly damaged (for example due to transportation);
•it has been stored for a long period of time in adverse conditions (exposure to direct light, heat sources
or places saturated by gas or vapours) or in environments with conditions different from those
mentioned in this manual.
•Device maintenance
If used correctly and in a suitable environment, the instrument does not require maintenance procedures.
It is recommended to occasionally clean the instrument case with a damp cloth and a mild detergent. This
operation must be performed with the instrument off.
The housing is in ABS / PC (acrylonitrile butadiene styrene / polycarbonate). This material is sensitive to
some organic solvents, for example toluene, xylene and methyl ethyl ketone (MEK).

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If liquids get into the housing, they could damage the instrument.
Do not open the instrument housing: it does not contain parts that can be maintained, repaired or replaced
by the user. In case of problems with the instrument, contact your local distributor.
It is recommended to use original spare parts only. Contact your local distributor for information. The use
of non-original spare parts can lead to malfunction or permanent damage to the instrument. Moreover, the
use of spare parts not guaranteed by the supplier can be dangerous for the user himself.
For the maintenance of the electrochemical sensors, refer to the documentation present in their packaging
or contact the supplier.
•Responsibility of the owner of the instrument
The person who owns and uses the tool or authorizes its use by other people is the owner of the tool and
is responsible for the safety of all users of the tool and third parties.
The owner of the instrument must inform users of the use of the same safely in their workplace and on the
management of potential risks, also providing the required protective devices.
When using chemicals or solvents, follow the manufacturer's safety data sheets.
Instrumental features
•Parameters
OXY 7 Vio: % O2, mg/l, mbar, Temp
•Datasheet
OXY 7 Vio (polarographic sensor)
Dissolved O2
Measuring range
0,00…19,99 mg/l / 20,0…50,0 mg/l - ppm
Resolution
0,1 / 0,01
Accuracy
± 1,5% F.S. (full scale)
Dissolved O2 saturation measuring range
0,0…199,9 % / 200…400%
Resolution
0,1 / 1%
Accuracy (with sensor)
± 10%
Oxygen calibration points
1 or 2 automatic
Calibration points indication
Yes
Calibration report
Yes
Barometric pressure measuring range
0…1100 mbar
Resolution
1 mbar
Accuracy
± 0,5%

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Automatic temperature compensation ATC
Yes
Temperature
Measuring range
0,0…100,0 °C
Resolution
0,1°C
Accuracy
± 0,5°C
Temperature compensation ATC and
MTC
Yes
Salinity
Measuring range
0…50 ppt
Salinity compensation
Yes, manual
System
Display
High definition color LCD
Brightness and contrast management
Manual
IP protection
IP 57
Power supply
AA 1,5 V – 3 batteries
Sound level during standard operation
< 80 dB
Environmental operating conditions
0 … +60 °C
Maximum permissible humidity
< 95 % non-condensing
Maximum altitude of use
2000 m
System dimensions
185 x 85 x 45 mm
System weight
400 g
Reference regulations
EMC 2014/30/UE
RoHS 2011/65/EU
EN 61326-1
EN 61010-1
Instrument description
•Display
Measurement
parameter
Indication of
instrumental
mode
Representation of
buffers used for
calibration
Error symbol
Actual value / Measure unit
Temperature and type of
compensation
ATC - automatic NTC 30KΩ
MTC - manual
Information icons
on connectivity and Data
Logger
Stability
indicator
Text string
Battery charge level
Text string

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•Keyboard
•LED
All the instruments are equipped with a two-colour LED (red and green) which provides the user with
important information on the status of the system:
Function
LED
Description
Power on
Fixed
Power off
Fixed
Standby
Flashing every 20 s
Stable measure
Flashing every 3 s
Errors during calibration
Flashing every 1 s
Errors during measurement
Flashing every 3 s
Selection confirmation
Switched on for 1 s
Timed screens
Fixed
Installation
•Supplied components
The instrument is always supplied inside the specific carrying case with these accessories:
batteries, standard 0 oxygen, paper tissues, screwdriver, beacker, multilingual user manual and test report.
Contact your local distributor to be updated on the correct composition of the sales kit.
•Start-up
•The device leaves the factory ready to be used by the user.
•Batteries are included.
Down directional key to scroll through
the menus
Enter / Menu key to confirm the chosen values
and enter the setup from the measure mode
On-Off button to
switch the device on
and off
Meas / Cal key to return to measure
mode and to start calibration
UP/MODE directional key for
scrolling through
menus and
parameters

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•Turning on and off
Turn on the system by pressing the button . The display initially activates all segments and then
appears:
•model and firmware of the instrument;
•settings relating to the most important parameters
Nota: every time the instrument is turned on after use, automatically the Polarization Time will start
(next Paragraphs)
•Replacement of batteries
The instrument works with 3 AA 1.5V batteries.
To proceed with the replacement:
1. Turn off the device.
2. Turn the instrument over with the display facing down and place it on a stable surface.
It is advisable to put a cloth to avoid any scratching on display.
3. Using the screwdriver supplied, completely unscrew the screw close to the battery symbol.
4. Remove the battery stopper cap with the help of the lanyard.
5. Remove the 3 exhausted batteries (one in the left compartment and two in the right compartment)
and insert the new ones. Pay attention to the correct polarity. Follow the diagram above the battery
symbol in the rear compartment of the instrument.
6. Reinsert the battery holder and tighten the screw.
•Instrument transportation
The instrument is always supplied with the appropriate carrying case. Use the original case only, to transport
the instrument. If you need to buy it again, contact your local distributor.
The interior of the case is shaped to be able to house the instrument and the sensors still connected.
•Key functions
Button
Pression
Function
Short
Press to turn the device on or off.
Short
In measure mode, press to scroll through the different parameters:
•OXY 7 Vio: % O2mg/l mbar
Short
•In calibration mode, press to return to measure mode.
•In measure mode, press to start the calibration.
Short
In measure mode, press to enter the setup.
In the setup menus, press to select the desired program and / or value.
During calibration, press to confirm the value.

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Short
In the setup and subset menus press to scroll
In the setup submenus, press to change the value
In MTC and customer calibration mode, press to change the value.
Long-press
(3s)
In measure mode, keep one of the two keys pressed to change the temperature
in MTC mode (manual compensation, without probe). When the value starts to
flash, the user can change the temperature value by entering the correct one and
confirming with .
IMPORTANT:
•When the Sleep mode is active (by default after two minutes of inactivity of the instrument) press
any key to reactivate the brightness of the display.
•Only at this point do the keys regain their function.
•Inputs / Outputs connections
Use original accessories guaranteed by the manufacturer only.
If necessary, contact your local distributor.
The BNC connectors are protected by a plastic cap.
Remove the cap before connecting the probes.
OXY 7 Vio top panel
READ THE MANUAL BEFORE PROCEEDING TO CONNECT THE PROBES OR PERIPHERALS
BNC for polarographic sensor
RCA for temperature probe
of the polarographic sensor

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•Symbols and icons on the display
Symbol
Description
Symbol
Description
Press the directional keys to change the
parameter or value on the display
Error in measurement or calibration
Measurement stability indicator Battery charge indication
The bars scroll if the measurement is
not stable
Operation of the device
•After the switching on, the instrument enters measure mode in the last screen before turning off.
•To scroll through the different parameter screens, press the key .
Sequence of parameters in measure mode:
OXY 7 Vio
% O2
mg/l
mbar
Note: Pressing the button after the last parameter, the instrument automatically restarts from the
first one.
In the measurement screen for %O2and mg/l, press the key to start the calibration of the active
parameter (next paragraphs).
On the left side of the display, through a string of different colours, it is always indicated how the
instrument is located.
Note: in order to confirm to the user the switching from one mode to another, the string flashes.

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String
Meaning
The instrument is in measure mode.
The instrument is in calibration
The user is in the setup mode.
The configuration menus can concern the characteristics of the
parameters or the general setting of the instrument.
Setup Menu
•In measure mode, press the key to enter SETUP mode, select the parameter to edit by using the
directional keys and confirming with key .
OXY 7 Vio
DO SETTINGS
SETTINGS
•Within the selected menu, move between the different programs using the directional buttons and
press the button to access the submenu you want to edit.
•Using the keys and choose the desired option or change the numerical value and
confirm with .
•The value or parameter that is being edited is recognizable as it flashes on the display.
•The icon indicates that the value or parameter to choose is editable using the directional keys.
•Press the key to return to the previous menu.

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•Setup menu structure
P5.0
DO SETTINGS
P5.1
Cal 0
P5.2
Salt Compensation
P5.6
Cal Data
P5.8
Reset Settings
P5.9
Temp Cal
P9.0
SETTINGS
P9.1
Temperature U.M.
P9.3
Backlight mode
P9.4
Brightness
P9.5
Sleep Mode
P9.8
Reset Settings
P9.9
Auto Power-Off
Temperature measurement ATC – MTC
•ATC: The direct measurement of the sample temperature for all parameters is carried out through the
NTC 30KΩprobe, integrated into the sensor.
•MTC: If no temperature probe is connected, the value must be changed manually: keep pressed
or until the value starts to flash; then adjust it by continuing to use the directional keys; press
to confirm.
Note: with the polarographic sensor supplied together with the instrument, the manual temperature
compensation (MTC) IS NOT TO BE PERFORMED.
%O
2
Parameter
Connect the polarographic sensor to the RCA / CINCH Temp connectors in the top panel of the device.
It is not necessary connect an external temperature probe, because it is already integrated.
•O2parameter Setup
•In measure mode press to access the SETUP menu.
•Press the button to access the DO SETTINGS P5.0 menu.
•Move with the keys and to select the program to access.
The table below shows the setup menu structure for the O2parameter, and for each program the options

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that the user can choose and the default value:
•Composition of the Setup menu for O2Parameter
Program
Description
Options
Factory Default Settings
P5.1
CAL 0
-
-
P5.2
SALT COMPENSATION
0.0 – 50.0
0.0
P5.6
CALIBRATION DATA
-
-
P5.8
RESET SETTINGS
YES – NO
NO
P5.9
TEMPERATURE CAL
YES – NO
-
P5.1 Cal 0 (Calibration with Standard Zero 02)
•Access this setup menu to select the calibration with Standard (supplied together with the device in the
carrying case) Zero Oxygen (next paragraphs “Calibration”).
•Once confirmed the operation, in measure mode on the lower left in the display, the beaker
indicates the point % 02= 0 on which the calibration was performed.
P5.2 Salt Compensation (manual)
The salinity of the sample to be measured influences the partial pressure of the dissolved oxygen. For a
correct measurement, it is necessary to set the salinity value of the sample. If oxygen measurements are
carried out on salt or sea water samples, it is important to modify the measurement by setting the indicative
salinity value of the sample.
The default value is 0 ppt, access the parameter SALT COMPENSATION P5.2 of the setup menu to change it
and select the desired value between 0.0 … 50ppt.
The average salinity of the sea water is 35ppt.
P5.6 Calibration data O2
Access this menu to get information on the last performed calibration. The following screens will
automatically scroll on the display:
•First screen: Beakers indicating the points (0% - 100% O2) on which the calibration was performed.
•Second screen: OFFSET value of the sensor expressed in %.
•Third screen: EFFICIENCY of the sensor, expressed in Slope %.
•Fourth screen: Value of COMPENSATION of Salinity, expressed in ppt.
•Fifth screen: Value of BAROMETRIC PRESSURE, expressed in mbar, at which the calibration was
performed.
•Sixth screen: TEMPERATURE at which the calibration was performed.
Note: The instrument accepts calibrations with Oxygen sensors with Slope % between 80 – 120%.
Outside this range of acceptability, the instrument does not allow to end the calibration and displays the
error message SLOPE OUT OF RANGE
(consult the paragraph 11 Probe Do 7 maintenance)

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P5.8 Reset of the DO parameter (Reset Settings)
If the instrument does not work properly or incorrect calibrations have been carried out, confirm YES with
button , in order to take all the parameters of the DO menu back to the default settings.
P5.9 Temperature calibration
All the instruments of this series are pre-calibrated for a correct temperature reading. However, if there is a
difference between the measured and the real temperature (usually due to a probe malfunction), it is
possible to perform an offset adjustment of + 5°C.
After the connection of the temperature probe, use the keys and to correct the temperature
offset value and confirm with .
•Information about sensor DO 7
The probe DO7 is polarographic with integrated temperature sensor. The oxygen sensor uses a BNC
connector, while the temperature sensor uses an RCA (Chinch) connector.
Membrane cap
•Sensing element
The permeable membrane allows the passage of only gas present in the sample to be analysed, blocking
the passage of liquids. The oxygen reacts with the electrolytic solution, after passing through the membrane,
and changes its chemical and physical properties depending on oxygen concentration. The sensing elements
detect this change and generate a signal depending on the amount of dissolved oxygen. The oximeter reads
this signal and returns the value on the display.
•Membrane
The membrane, which must allow only passage of oxygen, must be in perfect conditions.
If it presents any ripples, irregularities or is punctured, it must be replaced with a new one.
•Electrolyte
The electrolyte is an alkaline solution that reacts to the presence of oxygen, it saturates with wear and over
time, therefore, it must be replaced regularly.
•Polarization time
The polarographic sensor needs to be polarized before performing the measurements.
Integrated temperature
sensor

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Connect the probe to the instrument and switch on with button ; the device turns on and starts the
countdown for the polarization time. At the end of the countdown, the meter enters in measure mode
and it is ready to perform measurements.
The polarization time is 10 minutes. However, if the instrument is turned off for less than an hour, the
polarization time will reduce proportionally.
•New sensor with new instrument
The sensor is supplied with the membrane filled with electrolyte; it is necessary to hydrate the membrane
dipping it in distilled water for half an hour. Switch the device on and wait for the polarization time.
•Probe storage
When the probe is not in use, store it in the storage cap containing distilled water. In this way, the
membrane is protected and hydrated, ready for use.
•Not using the sensor for long period of time: over one month
If the instrument and the sensor are not used for a long period of time (over one month), it is recommended
to empty the membrane from the electrolyte and wash the probe accurately. Dry the sensor and screw the
membrane without electrolyte, protecting the sensor with its rubber cap.
•Oxygen sensor calibration
The polarographic sensor is an active sensor which changes its response with wear and aging; therefore,
it is necessary to perform the calibration regularly in air.
•Calibration in air at 100%
The ordinary calibration is performed at 100% in air.
Turn the instrument on, dip the probe in water and wait for the polarization time of 10 minutes.
Later, dry the probe thoroughly with paper towel and proceed as follows:
•Place the probe in air with the membrane facing downwards and wait for 2 minutes. Then, connect the
sensor to the device.
•In measure mode, press the key to enter in calibration mode.
On the display, it appears the string “POINT oxy 100.0”; the device will look for the value %O2= 100 %.
Keep the sensor in air in a vertical position with the membrane facing downwards.
•When the signal is stable, the red bands will be replaced by the stability icon .
Press the button , as indicated by the string “PRESS OK”.
On the display, the measured value flashes, then the sensor and finally the beacker appears
below on the left and indicates that the instrument is calibrated on value 100%O2.
•After the calibration, the instrument enters in measure mode automatically.

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•Calibration with zero oxygen standard
Normally, it is enough to calibrate the instrument in air at 100%, as explained previously. However,
sometimes it is also necessary to calibrate at 0%, for example when:
•A probe is replaced by a new one
•The probe is not used for a long period of time (over one month)
•A complete maintenance of the sensor is performed
•The instrument does not calibrate at 100%, in this case calibrate it before at 0%.
•The instrument does not measure correctly
For calibration at 0%, proceed as follows:
Before proceeding, perform a maintenance of the probe DO 7. (chapter 11)
Turn the instrument on, dip the probe in the water and wait for the polarization time of 10 minutes. Then,
dry the probe thoroughly with paper towel and proceed as follows:
•Put the probe in the Zero Standard Oxygen and wait for 5 minutes.
•In measure mode, press the button , remain in Menu DO SETTINGS P5.0 and confirm pressing
the button again.
•Press the button again, confirm the entry into submenu CAL 0 P5.1.
•On the display, the string “POINT oxy 0.0” appears; the device will search for the value %O2= 0%.
•Gently stir the probe in the Standard and eliminate any air bubbles under the membrane, moving the
sensor.
•The scrolling on the display of four red bands means that the measurement is not stable yet.
•Consider the measurement truthful only when the stability icon appears .
•Confirm the value by pressing the button .
•The instrument automatically returns to measure mode.
•The beaker icon appears at the bottom left, indicating that the instrument is calibrated on value
0% O2.
ATTENTION: Before proceeding with the calibration operations, carefully consult the safety data sheets
of the substances involved:
•Zero oxygen Standard calibration solution
Note: The Zero Oxygen Standard Solution is SINGLE DOSE! After its use, contact your local distributor for
the purchase.
Perform the calibration in air at 100% too. This procedure remains saved, even after the
turning off of the device.

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•Calibration range
The time range between two calibrations (100% in air) depends on the type of the sample, the efficiency of
the electrode and the researched accuracy; usually, it is necessary to calibrate the instrument at least once
a week, but for a better accuracy, it is recommended to calibrate it more often.
The instrument must be recalibrated, if occurs one of the following conditions:
•New probe, or probe not used for a long time
•After the sensor maintenance.
•Errors during calibration
•NOT STABLE:The button was pressed with still unstable signal. Wait for the icon to appear
to confirm the point.
•WRONG BUFFER: The buffer is polluted or not part of the recognized families.
•SLOPE OUT OF RANGE: The slope of the sensor calibration line is out of the acceptable range 80 - 120%.
•CALIBRATION TOO LONG: The calibration exceeded the time limit: only the points calibrated up to that
moment will be kept.
Dissolved oxygen measurement
•Before starting
In order to reduce measurement errors and get the greatest possible accuracy, observe the following rules
before starting:
•The sensor must be calibrated;
•The sensor must be placed in a vertical position with the membrane downwards;
•Remove the protective cap;
•The sensor must be at the same temperature of the sample to analyse; if necessary, leave the probe
immersed in the sample until the reaching of thermal equilibrium.
•Measure Mode
The instrument can work in two different measure modes:
•Dissolved O2Saturation expressed in %
•Dissolved O2 Concentration expressed in mg/l, corresponding to ppm
mg/l = ppm
•Barometric pressure
During the measurement press the button , in order to change the unit of measurement.