Hanna Instruments HI 88703 User manual

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www.hannainst.com
HI 88703
Turbidity Meter
Instruction Manual

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TABLE OF CONTENTSTABLE OF CONTENTS
TABLE OF CONTENTSTABLE OF CONTENTS
TABLE OF CONTENTS
Dear Customer,
Thank you for choosing a Hanna Instruments product. This manual will provide you with the
necessary information for correct use of the instrument.
Please read this instruction manual carefully before using the instrument.
If you need additional technical information, do not hesitate to e-mail us at [email protected]
or see the back side of this manual for our worldwide sales and technical service contacts.
This instrument is in compliance with directives.
PRELIMINARY EXAMINATION ................................................................................................................... 3
GENERAL DESCRIPTION ........................................................................................................................... 3
ABBREVIATIONS ..................................................................................................................................... 4
PRINCIPLE OF OPERATION ...................................................................................................................... 4
FUNCTIONAL DESCRIPTION ..................................................................................................................... 6
SPECIFICATIONS ..................................................................................................................................... 8
GENERAL TIPS FOR AN ACCURATE MEASUREMENT .................................................................................... 9
START UP ............................................................................................................................................ 15
RANGE SELECTION ................................................................................................................................ 16
TUTORIAL MODE .................................................................................................................................. 16
HELP MODE .......................................................................................................................................... 17
MEASUREMENT PROCEDURE FOR RATIO/NON RATIO TURBIDITY RANGE .................................................. 17
CALIBRATION PROCEDURE FOR RATIO/NON RATIO TURBIDITY RANGE ..................................................... 20
GOOD LABORATORY PRACTICE (GLP) ...................................................................................................... 25
RESTORE FACTORY CALIBRATION ........................................................................................................... 25
LOG & LOG RECALL ............................................................................................................................... 26
SETUP ................................................................................................................................................. 27
LAMP REPLACEMENT ............................................................................................................................. 30
FUSE REPLACEMENT .............................................................................................................................. 30
PC INTERFACE ....................................................................................................................................... 30
ACCESSORIES ....................................................................................................................................... 31
WARRANTY ........................................................................................................................................... 31
RECOMMENDATIONS FOR USERS .......................................................................................................... 31

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Please examine this Product carefully. Make sure the instrument is not damaged. If any damage has
occurred during the shipment, please notify your dealer.
This HI 88703 Bench Turbidity meter is supplied complete with:
• Five Sample Cuvets and Caps
• Calibration Cuvets for turbidimeter
• Silicone Oil
• Tissue for wiping the cuvets
• Power cord
• Instruction Manual
• Instrument Quality Certificate
Note:Save all packing material until you are sure that the instrument works correctly. Any
defective item must be returned in the original packing with the supplied accessories.
PRELIMINARY EXAMINATIONPRELIMINARY EXAMINATION
PRELIMINARY EXAMINATIONPRELIMINARY EXAMINATION
PRELIMINARY EXAMINATION
HI 88703 is a high accuracy, meter that benefits from Hanna’s years of experience as manufacturer
of analytical instruments.
The HI 88703 is especially designed for water quality measurements, providing reliable and
accurate readings on low turbidity. The HI 88703 meets and exceeds the requirements of USEPA
and Standard Methods.
The instrument is based on a state-of-the-art optical system which guarantees accurate results,
assures long term stability and minimizes stray light and color interferences. It also compensates for
variations in intensity of the lamp, making no need for frequent calibration.
The 25 mm round cuvets made from special optical glass guarantee the repeatability and consistency
of the measurements.
Turbidity measurements can be made in the 0.00 to 4000 NTU (Nephelometric Turbidity Units)
range when ratiometric measurements are used and in the 0.00 to 40.0 NTU range when non ratio
method is used. The instrument has an EPA compliance reading mode which rounds the reading to
meet EPA reporting requirements. Alternative EBC and Nephelos measuring units are available.
Depending on the measured sample and needed accuracy, normal measurement, continuous
measurement or signal averaging measurement can be selected.
A two, three, four or five-point calibration could be performed by using the supplied (<0.1, 15,
100, 750 and 2000 NTU) standards. When user prepared standards are used, the calibration points
can be modified.
GENERAL DESCRIPTION
GENERAL DESCRIPTIONGENERAL DESCRIPTION
GENERAL DESCRIPTIONGENERAL DESCRIPTION
GENERAL DESCRIPTION

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ABBREVIATIONSABBREVIATIONS
ABBREVIATIONSABBREVIATIONS
ABBREVIATIONS
NTU Nephelometric Turbidity Units
JTU Jackson Turbidity Units
FTU Formazin Turbidity Units
USEPA US Environmental Protection Agency
LCD Liquid Crystal Display
RTC Real Time Clock
RH Relative Humidity
ID Identification
EBC European Brewery Comitee
Turbidity is the optical property that causes light to be scattered and absorbed, rather than transmitted.
The scattering of the light that passes through a liquid is primarily caused by the suspended solids. The
higher the turbidity, the greater the amount of scattered light. Because even the molecules in a very pure
fluid scatter light to a certain degree, no solution will have zero turbidity.
The USEPA Method 180.1 specify the key parameters for the optical system to measure turbidity
for drinking, saline and surface water in a 0 to 40 NTU range, using the nephelometric method.
The HI 88703 instrument is designed to meet or exceed the criteria specified by the USEPA Method
180.1 and Standard Method 2130 B.
The light beam that passes through the sample is scattered in all directions. The intensity and pattern
of the scattered light is affected by many variables like wavelenght of the incident light, particle size
and shape, refractive index and color.
The optical system includes a tungsten filament lamp, a scattered light detector (900) and a
transmitted light detector (1800).
PRINCIPLE OF OPERATIONPRINCIPLE OF OPERATION
PRINCIPLE OF OPERATIONPRINCIPLE OF OPERATION
PRINCIPLE OF OPERATION
HI 88703 has complete G.L.P. (Good Laboratory Practice) functions that allows traceability of the
calibration conditions. The last calibration points, time and date can be checked.
HI 88703 has a user-friendly interface with an easy to understand, graphical LCD. All messages are
in plain text, easy to read and understand. Comprehensive contextual help is available at a simple
key press. All messages and helps are available in several languages. Confirmation and error acoustic
signals help the user during instrument operation. Furthermore, a tutorial mode of operation guides
the user step by step through the analysis process.
The instrument’s logging function offers complete information for the measurement. Up to 200
measurements can be stored in the internal memory and consulted at any time. In order to further
store or analyse, the data can be downloaded to a PC using the USB port.

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For the ratio turbidimeter range, the microprocessor of the instrument calculates the NTU value, from
the signals that reaches the two detectors, by using an effective algorithm. This algorithm corrects
and compensates for interferences of color, making the HI 88703 instrument color-compensated.
The optical system and measuring technique compensate also for the lamp intensity fluctuations,
minimizing the need of frequent calibration.
For the non ratio turbidimeter range, the NTU value is calculated from the signal on the scattered
light detector (90°). The method offers a high linearity on the low range. The method is more
sensitive to the lamp intensity fluctuations.
The lower detection limit of a turbidimeter is determined by the so called “stray light”. Stray light is the light
detected by the sensors, that is not caused by light scattering from suspended particles.
The optical system of HI 88703 instrument is designed to have very low stray light, providing accurate
results for low turbidity samples. However, special care must be taken when measuring low turbidities (see
page 9 “General Tips for an Accurate Measurement” for sample preparation and measuring techniques).
MEASUREMENT UNITS
The most used units for turbidity are NTU (Nephelometric Turbidity Units). In the beer industry a
common unit is EBC (European Brewery Comitee).
The HI 88703 turbidimeter reports the measurements in NTU, EBC or Nephelos. One NTU is
equal with 0.245 EBC or 6.7 Nephelos.
Calibration and measurements are done only in NTU and the results in other units are obtained
by multiplying with the respective factors.

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FUNCTIONAL DESCRIPTIONFUNCTIONAL DESCRIPTION
FUNCTIONAL DESCRIPTIONFUNCTIONAL DESCRIPTION
FUNCTIONAL DESCRIPTION
INSTRUMENT DESCRIPTION
1) Liquid Crystal Display (LCD). The LCD has backlight for better visibility in dark environments.
2) Keypad. Splash proof resistant.
3) Cuvet Lid. Close the cuvet lid prior to start a measurement.
4) Lamp lid and the related fixing screw
5) USB connector
6) Fuse holder
7) Mains switch
8) Mains connector

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DISPLAY DESCRIPTION
The display contains the following fields:
1) The current time in selected format
2) Information related to the measurement
3) Functional keys
4) Currently selected parameters
5) Measuring units
6) Measured value
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1
2
6
5
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KEYBOARD DESCRIPTION
The keyboard contains 8 direct keys and 3 functional keys with the following functions:
The function of each of the three functional keys depends on the name
displayed on the LCD above them.
ESC
Press to return to the main screen.
RANGE
When in the main screen, press to access the change parameter screen.
Press to move up in menu and help or to increment a set value.
LOG
Press to move down in menu and help or to decrement a set value. Press
to log the current reading.
CAL
Press to access calibration menu.
RCL
Press to recall the log.
HELP
Press to display the help screen.
SETUP
Press to access the setup screen.

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SPECIFICATIONSSPECIFICATIONS
SPECIFICATIONSSPECIFICATIONS
SPECIFICATIONS
Range - non ratio mode 0.00 to 9.99; 10.0 to 40.0 NTU
0.0 to 99.9; 100 to 268 Nephelos
0.00 to 9.80 EBC
Resolution - non ratio mode 0.01; 0.1 NTU
0.1; 1 Nephelos
0.01 EBC
Range - ratio mode 0.00 to 9.99; 10.0 to 99.9; 100 to 4000 NTU
0.0 to 99.9; 100 to 26800 Nephelos
0.00 to 9.99; 10.0 to 99.9; 100 to 980 EBC
Resolution - ratio mode 0.01; 0.1; 1 NTU
0.1; 1 Nephelos
0.01; 0.1, 1 EBC
Range selection Automatically
Accuracy ±2% of reading plus 0.02 NTU (0.15 Nephelos; 0.01 EBC)
±5% of reading above 1000 NTU (6700 Nephelos; 245 EBC)
Repeatibility ±1% of reading or 0.02 NTU (0.15 Nephelos; 0.01 EBC)
whichever is greater
Stray Light < 0.02 NTU (0.15 Nephelos; 0.01 EBC)
Light Detector Silicon Photocell
Method Nephelometric method (90°) or Ratio Nephelometric Method
(90° & 180°), Adaptation of the USEPA Method 108.1 and
Standard Method 2130 B.
Measuring mode Normal, Average, Continuous.
Turbidity Standards <0.1, 15, 100, 750 and 2000 NTU
Calibration Two, three, four or five-point calibration
Light Source Tungsten filament lamp
Lamp life greater than 100,000 readings
Display 40 x 70mm graphic LCD (64x128 pixels) with backlight
LOG Memory 200 records
Serial Interface USB
Environment 0°C (32°F) to 50°C (122°F); max 95% RH non-condensing
Power supply 230 V/50 Hz or
115 V/60 Hz 20 W
Auto Shut-off After 15 minutes of non-use
Dimensions 230 x 200 x 145 mm (9 x 7.9 x 5.7”) L x W x H
Weight 2.5 Kg (88 oz.)

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Note: If you are using multiple cuvets, always match the cuvets.
CUVET HANDLING
The cuvets should be free of scratches or cracks. Any cuvet with visible scratches will be
discarded. The cuvets should be periodically washed with acid. After washing, the cuvets should
be well rinsed multiple times with distilled or deionized water. Allow cuvets to air-dry and store
them for long periods of time with caps, to avoid dirt entering inside. Always handle the cuvet
by touching only the cap or its top side (over the horizontal line).
Always store the cuvets in separate boxes or with separators between them to avoid scratches on
the surface.
CUVET PREPARATION
Whenever a cuvet is used, it must be clean inside and outside. When it is placed into the
instrument, it must be dry outside, completely free of fingerprints or dirt.
GENERAL TIPS FOR AN ACCURATE MEASUREMENTGENERAL TIPS FOR AN ACCURATE MEASUREMENT
GENERAL TIPS FOR AN ACCURATE MEASUREMENTGENERAL TIPS FOR AN ACCURATE MEASUREMENT
GENERAL TIPS FOR AN ACCURATE MEASUREMENT
HI 88703 is a highly accurate combined meter for turbidity and free & total chlorine. To meet the
instrument’s performance and fully benefit of its features, it is very important for the analyst to use
proper measurement techniques for accurate, precise and repeatable readings. Special care must be
taken during sample preparation and handling. The instructions listed below should be carefully
followed during measuring and calibration to ensure best accuracy.
GENERAL RULES
• Always put the instrument on a flat, rugged surface when taking measurements.
• Do not operate in direct sunlight.
• Keep the lid of the instrument closed when it is not used to prevent dust or dirt entering inside.
• Always close the lid of the instrument during measurement.
• Always use cuvets without scratches or cracks because they can cause inaccurate readings.
• Always cap the cuvets to avoid spillage of the sample into the instrument.
• Do not use too much oil to prevent contamination of the optical system.
• If possible use indexed and matched cuvets.
• If possible use the same cuvet for zero and read for Free and Total Chlorine measurements.
CUVET
The cuvet is part of the optical system in all measurements. The light reaches the sample by
passing through the cuvet glass. As a result, the measurement can be affected by the glass
imperfections, dirt, dust, scratches, or fingerprints present on the cuvet surface. Special care must
be taken in preparing and handling the cuvet.

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If the cuvet is not indexed, put the cuvet with the factory mark aligned with the sign on the
instrument top.
CUVET OILING
To hide minor imperfections and scratches, the cuvets should be oiled outside with the supplied silicone oil.
This is very important, especially for low turbidity samples (< 1 NTU), otherwise scratches can contribute
and alter turbidity readings.
The silicone oil has the same refractive index as the glass and will not alter the turbidity readings. It is
important to apply only a thin layer of silicone oil.
Warning: Do not apply silicone oil in excess because it may retain dirt or contaminate the cuvet
holder of the instrument, altering the turbidity readings.
It is very important to apply the silicone oil on a clean, dry cuvet. Apply a few drops of oil and wipe
the cuvet thoroughly with a lint-free cloth. Wipe off the excess oil till you obtain a thin, uniform
layer. If the procedure is correctly followed, the cuvet should appear nearly dry with no visible oil.
Note: The supplied cloth for oiling should be stored together with the silicone oil bottle and cuvets,
taking care to avoid contamination with dirt. After a few oiling procedures, the cloth will
contain enough oil to wipe the bottle with it without adding more oil. From time to time add
some drops of oil on the cuvet to provide the necessary oil quantity in the cloth.
INDEXING A CUVET
It is very important for low turbidity readings to always insert the cuvet into the instrument in the
same position.
All cuvets are factory indexed. This index can be used to put the cuvet with the factory mark on the
cuvet aligned with the sign on the instrument top.
To further reduce the effect of glass imperfections, the cuvet can be indexed and use this new index
as the position mark.

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For indexing one cuvet or matching multiple cuvets, the continuous reading mode is suggested. In this
mode multiple successive readings are taken without turning off the lamp. The turbidity is immedi-
ately displayed, reducing considerably the measurement time.
Note: The instrument can not perform continuous readings if the average mode is on.
In order to index a cuvet follow the next steps:
• Fill the cuvet with high quality water (<0.1 NTU)
up to the 10 mL mark.
• Clean and oil the cuvet as described before.
• Turn the instrument ON.
• Insert the cuvet into the instrument and press
“Read” functional key. Record the reading.
• Open the instrument lid, slightly rotate the cuvet
and take a new reading.
• Repeat the last step until you read the lowest NTU value.
• Alternatively, keep the “Read” functional key pressed to make continuous readings. After the
first value is displayed, open the lid and start rotating the cuvet until the lowest NTU value is
displayed.

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• Mark this position on the thicker white band on
the top of the cuvet with a water resistant pencil.
• Always use this position to align it with the
sign on the instrument top.
In order to match multiple cuvets follow the next
steps:
• Fill some cuvets with high quality water
(<0.1NTU) up to the 10 mL mark.
• Clean and oil the cuvets as described before.
• Turn the instrument ON.
• Insert the first cuvet into the instrument and
press “Read” functional key. Record the
reading.
• Mark this position on the thicker white band on
the top of the cuvet with a water resistant pencil.
MATCHING MULTIPLE CUVETS
Precise measurements require the use of a single cuvet. If it is not possible, cuvet selection and
matching must be performed before taking measurements.

• Open the instrument lid, slightly rotate the
cuvet and take a new reading.
• Repeat the last step for the second cuvet until the reading is within 0.01 NTU of the value
obtained for the first cuvet.
• Alternatively, keep the “Read” functional key pressed and, after the first value is displayed,
open the lid and start rotating the cuvet until the read value matches the first cuvet.
• Mark this position on the second cuvet with a water resistant pencil.
• Follow the same procedure for all the cuvets you need.
Note: If the cuvet is indexed, use the index to position it in the instrument.
SAMPLING TECHNIQUE
When taking turbidity measurements it is very important to select a representative sample. For
consistent results, follow the next tips when sampling:
• Gently mix the water before taking the sample.
• If the sample is taken from a pipe, discard the first few liters.
• If measuring a non uniform source, collect samples from different places and mix them.
When measuring the collected sample, keep in mind the following:
• Samples should be analyzed immediately after collection because the turbidity can change in time.
• To avoid dilution of the sample it is better to rinse the cuvet with a quantity of sample and then
discard. Only after this you can fill the cuvet with sample.
• Pay attention that cold samples do not condense on the sample cell.
REMOVING AIR BUBBLES (TURBIDITY only)
Any air bubbles present in the sample will cause high turbidity readings. To obtain accurate
measurements, remove the air bubbles using one of these methods:
• Application of a partial vacuum;
• Addition of a surfactant, such as Triton X-100;
• Insert the second cuvet into the instrument and
take a reading.
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• Use of an ultrasonic bath;
• Heating the sample.
Sometimes it is necessary to combine two or more methods for efficient air bubble removal.
Note: Each method can alter the sample turbidity, if misused, so they have to be used with caution.
APPLICATION OF VACUUM
Vacuum works by decreasing the atmospheric pressure. In this way the bubbles from the solution
came out to the surface. Application of vacuum is a very simple procedure and can be applied with
any vacuum source at hand. The simplest equipment at hand is a syringe and a rubber stopper for
vacuum degassing.
Notes: • Pay attention that the vacuum equipment be clean and oil-free.
• It is not recommended to apply vacuum to a viscous sample that contains volatile
components. In such cases the vacuum can determine the volatile component of the
viscous sample to increase the bubbles from the sample.
ADDITION OF SURFACTANT
Surfactant addition works by changing the surface tension of the water. In this way bubbles are
released from the sample. This method is effective in samples that are supersaturated with air.
The procedure consists in the addition of a drop of surfactant in the cuvet before adding the sample
to be analyzed.
A convenient surfactant to use for degassing is Triton X-100.
Warning: Pay attention that changing the surface tension will cause a rapid settling of particles that
cause turbidity. To avoid this problem, analyze as soon as possible the sample.
Do not shake vigorously the sample because the surfactant may foam. If you are using the same
cuvet, rinse it before adding a new sample in order to avoid surfactant accumulation.
Surfactant contribution to the turbidity readings is negligible.
Note: Surfactant addition should be used for degassing only when other methods are ineffective.
USE OF AN ULTRASONIC BATH
The ultrasonic waves are very effective in removing air bubbles from samples. However, ultrasonic
waves should be used with care because they can alter sample turbidity characteristics, by modifying
the shape and size of particles which cause turbidity. The ultrasonic waves can also break the existing
air bubbles, leading to a complication of the degassing process.
In order to avoid excess application of the ultrasonic waves you can apply ultrasound until all visible
air bubbles are removed, and then measure the sample turbidity. This is the most used procedure for
degassing.
If you are not sure that all air bubbles were removed, apply ultrasonic waves again for a short period
of time and then measure the turbidity. Repeat this procedure until the turbidity is increasing instead
of decreasing, sign that turbidity of the sample was altered.
In order to degas a sample fill a clean cuvet with sample and immerse it (1/2 to 2/3 immersed) in

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STARTUPSTARTUP
STARTUPSTARTUP
STARTUP
The HI 88703 Turbidity bench is supplied with all necessary accesories for making measurements.
Unpack the instrument and place it on a flat surface. Do not place the instrument under dirrect
sunlight.
Connect the instrument to the mains with the provided power cord. Pay attention that the mains
voltage match the value printed on the back of the instrument.
Switch on the instrument. On the LCD, the Hanna Logo will appear for a short time, followed by the
main screen for ratio turbidity measurements.
The instrument loads the selected language. If no language can be loaded the instrument will work
in the “safe mode”. In “safe mode” all the messages are displayed in English and tutorial and
help information are not available.
an ultrasonic bath. Follow the degassing procedure described above. Only after the degassing
procedure is finished the cuvet can be capped.
HEATING THE SAMPLE
Use of heat to remove air bubbles, although very effective in some cases, should be handled with care
because it can alter the turbidity of the sample. When heating a sample, the volatile components
from the sample can vaporize, the suspended components can dissolve or the sample characteristics
can change.
Therefore, the heating procedure should be used with extreme care.
The best way is to use a warm water bath and immerse the cuvet with sample into the bath. Heat the
sample only until the visible bubbles are removed.
Note: Always cool the heated sample to the original sample temperature before measurement.
The heating procedure can be used in combination with vacuum or ultrasonic waves application for
a more effective air bubble removal.

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RANGE SELECTIONRANGE SELECTION
RANGE SELECTIONRANGE SELECTION
RANGE SELECTION
The HI 88703 instrument has two measuring
ranges: Ratio Turbidity, Non Ratio Turbidity. When
the instrument is in the main screen, the selected
range is displayed in the right side of the LCD, on
the message line.
To change the range, press the RANGE key.
When the display shows the Change parameter
screen, press UP or DOWN keys until the new
range is highlighted.
Press “CFM” functional key to select the new range.
The instrument returns to the main screen.
TUTORIAL MODETUTORIAL MODE
TUTORIAL MODETUTORIAL MODE
TUTORIAL MODE
The HI 88703 has a unique Tutorial Mode that provides additional information to help the unexperienced
user during the measurements. The instruments display a screen, with explanations and confirmation
button, each time when a preparation or other operation has to be performed by the operator. The
instrument resumes the measuring sequence when the operator confirms that the requested operation
was done.
To disable this mode, when in the main screen,
press the SETUP key to enter the setup, and then
press DOWN key until the “Tutorial” line is
highlited. Press the “Disable” functional key and
then press ESC to return to the main screen.

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HELP MODEHELP MODE
HELP MODEHELP MODE
HELP MODE
The HI 83414 offers an interactive context help mode that assists the user at any moment.
To access help screens, just press HELP.
Depending which menu you are in, a screen with
additional information will appear. To read all
available data, scroll down or up the text using
the UP or DOWN keys.
Press the “Support” functional key to access a page
with Hanna support centers and their contact details.
Press the “Accessories” functional key to access a
page with instrument accessories.
To exit support or accessories screens, press ESC, and
the instrument will return to the previous help screen.
To exit help mode just press the HELP key again and the meter will display the last screen the user
was in before entering help mode.
MEASUREMENT PROCEDURE FOR RATIO /MEASUREMENT PROCEDURE FOR RATIO /
MEASUREMENT PROCEDURE FOR RATIO /MEASUREMENT PROCEDURE FOR RATIO /
MEASUREMENT PROCEDURE FOR RATIO / NONNON
NONNON
NON RATIORATIO
RATIORATIO
RATIO
TURBIDITY RANGETURBIDITY RANGE
TURBIDITY RANGETURBIDITY RANGE
TURBIDITY RANGE
When taking turbidity measurements, several basic rules should be followed:
• Always use cuvets without scratches or cracks because they can cause inaccurate readings.
• Always cap the cuvets to avoid spillage of the sample into the instrument.
• Always close the lid of the instrument during measurement.
• Do not use too much oil to prevent contamination of the optical system.
To take turbidity measurements, follow the next steps:
• Turn the instrument ON by pressing ON/OFF.
When dashes are displayed on the LCD, the
instrument is ready. The current time appears on
the upper left corner of the display and the
range name appears on the lower right corner.
• Fill a clean, dry cuvet with 10 mL of sample up to the
mark, taking care to handle the cuvet by the top.
• Replace the cap.

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NORMAL MEASUREMENT
This type of measurement is best suited for regular readings, when the sample is stable and normal
accuracy is required. In normal mode, the measurement takes about 10 seconds and the lamp is ON
for a minimum period of time (about 7 seconds).
CONTINUOUS MEASUREMENT
This measurement mode is suitable when many measurements have to be taken in a short period of
time. The mode is useful to evaluate a very fast settling sample. This measurement mode is
recommended for indexing cuvets.
•Press “Read” functional key to take the
measurement.
The display will show “READ” in the left side
and blinking dashes. The dashes and lamp icon
will appear during different measurement
phases.
•The result is displayed in the selected units.
• Wipe the cuvet thoroughly with a lint-free cloth
to remove any fingerprints, dirt or water spots.
• Apply silicone oil on the cuvet and wipe with a
lint-free cloth to obtain an even film over the
entire surface of the cuvet.
Note: It is very important to oil the cuvet, espe-
cially for low turbidity values (< 1 NTU)
to hide the glass imperfections which can
influence the reading.
• Place the cuvet into the instrument. Align the
mark from the cuvet with the sign on the in-
strument top
• Close the lid.
Note: If you have a cuvet with indexing mark,
place the cuvet into the instrument with the
indexing mark aligned with the sign on the
instrument top.

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•Press “Read” functional key to take the
measurement.
The display will show “READ” in the left side and
blinking dashes. The icon for lamp will appear during
different measurement phases. The first value is
displayed after 10 seconds and then a new average of
the available readings is displayed each second. When
a new value is displayed, the measurement value will
blink briefly. The last averaged value remains on the
display at the end of the measurement.
•Press “Read” functional key and keep it pressed to take continuous readings.
The display will show “READ” in the left side and blinking dashes. The dashes and lamp icon will
appear during different measurement phases. The first value is displayed after 10 seconds and then
a new reading is displayed each second as long as the “Read” functional key is kept pressed. When
a new value is displayed, the measurement value will briefly blink.
The last value remains on the display after the “Read” functional key is released.
AVERAGED MEASUREMENT
This measurement mode is useful when samples that cause unstable readings are analyzed. By
averaging several readings, noise effect is reduced and accurate measurements can be taken.
This mode can also be selected when high accuracy measurements are needed. In the average mode
10 measurements are averaged in a short period of time (about 20 seconds).
To use the averaged reading mode first enter setup and enable the Average reading mode. The “AVG”
text will be displayed in the left side of the screen.
HI 88703 automatically selects the correct turbidity
range to display the results with the highest accuracy.
If the measured value is higher than 4000 NTU
(980 EBC or 26800 Nephelos), the display will
show the maximum value blinking and the message
“Out of range” on the message line.
UNITS CHANGE
To change the units, simply press the “Unit” functional key when a measurement is available. The
Nephelos value is obtained by multiply with 6.7 the NTU value. The EBC value is obtained by
multiply with 0.245 the NTU value.

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CALIBRATION PROCEDURE FOR RATIOCALIBRATION PROCEDURE FOR RATIO
CALIBRATION PROCEDURE FOR RATIOCALIBRATION PROCEDURE FOR RATIO
CALIBRATION PROCEDURE FOR RATIO //
//
/ NN
NN
NONON
ONON
ON RATIORATIO
RATIORATIO
RATIO
TURBIDITY RANGETURBIDITY RANGE
TURBIDITY RANGETURBIDITY RANGE
TURBIDITY RANGE
HI 88703 has a powerful calibration function that compensates for lamp aging or changing.
The calibration can be done using the suplied calibration solutions or user prepared standards.
HI 88703 turbidimeter is supplied with 5 AMCO standards: <0.1 NTU, 15 NTU, 100,
750NTU and 2000NTU. The Hanna standards are specially designed for this instrument.
Turbidity standards have a shelf life and should not be used after the expiration date.
Alternatively, formazin standards can be used. It is recommended that the turbidity value of
the prepared calibration solutions to be close to the default calibration points.
The first calibration point should be near 0 NTU, the second point can be chosen between 10 and
20 NTU, the third point between 50 and 150 NTU, the fourth point between 600 and 900 NTU and
the fifth point between 1500 and 2500 NTU.
UTNtseraeNotdnuoR
0.1-0.050.0
01-11.0
04-011
001-045
004-00101
0001-00405
0001>001
EPA MODE
To round the readings as EPA specifications press
the “EPA” functional key. The EPA text is displayed
on the left side of the LCD and the reading is rounded
as follows: