Hanna Instruments HI 84429 User manual

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Instruction Manual
HI 84429
TITRATABLE ACIDITY
MINITITRATOR & pH METER
for Dairy Products
99 Washington Street
Melrose, MA 02176
Phone [phone]
Toll Free 1-800-517-8431
Visit us at www.TestEquipmentDepot.com

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All rights are reserved. Reproduction in whole or in part is prohibited without the written consent
of the copyright owner, Hanna Instruments Inc., Woonsocket, Rhode Island, 02895 , USA.
Dear Customer,
Thank you for choosing a Hanna product. This manual will provide you with the necessary
information for the correct use of the instrument. Please read it carefully before using the meter.
TABLE OF CONTENTS
PRELIMINARY EXAMINATION................................................................................................. 3
GENERAL DESCRIPTION ........................................................................................................ 4
SPECIFICATIONS ................................................................................................................... 6
PRINCIPLE OF OPERATION .................................................................................................... 8
FUNCTIONAL DESCRIPTION ................................................................................................... 9
TITRATOR STARTUP ........................................................................................................... 12
SETUP CONFIGURATION MENU .......................................................................................... 13
ELECTRODE PREPARATION .................................................................................................. 18
ELECTRODE CALIBRATION PROCEDURE................................................................................. 19
pH BUFFER TEMPERATURE DEPENDENCE ............................................................................ 23
PUMP TUBE INSTALLATION................................................................................................. 24
PURGE .............................................................................................................................. 24
PUMP CALIBRATION PROCEDURE ........................................................................................ 26
TITRATION PROCEDURE ..................................................................................................... 29
pH MEASUREMENT ............................................................................................................ 34
TEMPERATURE CALIBRATION PROCEDURE (for technical personnel only) ............................... 38
TROUBLESHOOTING GUIDE ................................................................................................ 40
ELECTRODE CONDITIONING & MAINTENANCE ...................................................................... 41
ACCESSORIES .....................................................................................................................42
WARRANTY........................................................................................................................43

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Please examine this product carefully. Make sure that the instrument is not damaged. If any
damage occured during shipment, please notify your Dealer.
Each HI 84429 minititrator is supplied complete with:
•FC 260B pH electrode
•HI 5315 Reference electrode
•HI 7072 Filling solution (30 mL)
•HI 7662-M Temperature probe
•HI 84429-50 Titrant (100 mL)
•HI 84429-55 Standard (500 mL)
•HI 700640 Cleaning solution for milk deposits (2x20mL)
•pH 4.01 buffer solution (230 mL)
•pH 6.00 buffer solution (230 mL)
•pH 8.30 buffer solution (230 mL)
• Two 50 mL beakers
• Two 20 mL beakers
• Tube set with cap
• Stir bars (2 large)
• 12 Vdc power adapter
• One 1 mL syringe
• One capillary dropper pipette
• Instruction manual
Note: Save all packing material until you are sure that the instrument works correctly.
Any defective item must be returned in its original packing.
PRELIMINARY EXAMINATION

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The HI 84429 is an easy to use microprocessor-based automatic minititrator and pH meter designed
for the rapid and accurate analysis of Total Titratable Acidity in milk. By eliminating subjective
factors including color indicators, errors in mathematical calculations or erratic titrant additions from
the measurement, the HI 84429 makes Total Titratable acidity analysis precisely and totally
impartially. This will quickly become a valuable analysis tool in your dairy lab.
The instrument benefits from Hanna’s many years of experience as manufacturer of quality analytical
instruments. A clear and well-designed user interface makes the instrument intuitive and simple to
use. A dedicated HELP key aids in set-up, calibration, status and troubleshooting.
By simply pressing the Start key, the HI 84429 automatically starts pump operation and titrates the
sample to the end point. The HI 84429 has a simple and accurate peristaltic pump to ensure the best
accuracy and repeatability. By performing pump calibration with the Hanna standard provided, the
instrument accuracy is assured.
The instrument employs a powerful and effective built-in algorithm to analyze the pH response to
determine the exact pH endpoint, then uses this to make the necessary calculations. The Titratable
Acidity Determination is instantaneously display in user selected measurement units on the large dot
matrix display. The instrument is ready for the next analysis immediately!
Other features:
• Log on demand up to 100 samples (50 for pH measurement; 50 for titration results)
• GLP feature, to view last calibration data for pH electrode and pump
MEASUREMENT SIGNIFICANCE
Both pH and titratable acidity are used to measure milk acidity. A decrease in pH or increase in
titratable acidity indicates lactic fermentation has occurred, most likely due to bacterial activity. pH
and titratable acidity measurements, together with other tests available to the analyst, provide a
mechanism to ensure quality and freshness of the milk products.
The pH of milk (or other dairy products) is a measurement of the actual acidity of the milk at the time
of measurement. The measurement uses a pH electrode and pH meter that reads out directly in units
of pH (after calibrating the electrode and meter together using pH buffers). The pH of fresh milk is
slightly acidic typically falling between 6.50 to 6.70 pH at 25°C.
GENERAL DESCRIPTION

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Titratable acidity measures the total titratable acidity and differs from pH as it also includes the
buffering capacity of the milk constituents. Titratable acidity in dairy products, is determined by
titrating a sample with sodium hydroxide to a fixed endpoint pH (pH 7.00 or a phenolphtalein
endpoint of pH 8.30). The actual neutralization of milk occurs at an endpoint of pH 7.00, however,
standard methods utilize the phenolphtalein endpoint value. The results will differ depending upon
which endpoint is utilized. The endpoint can be determined visually using color change produced by
phenolphtalein indicator or less subjectively, using a pH electrode as the indicator in a potentiometric
acid-base titration.
Titratable acidity can be expressed in various units values:
Soxhlet Henkel degrees (°SH)- mostly used in Central Europe
This value is obtained by titrating 100 mL of milk with 0.25N NaOH, using phenolphtalein as
indicator.
Thorner degrees (°Th)- mostly used in Sweden and the CIS
This value is obtained by titrating 100 mL of milk, diluted with 2 parts of distilled water, with 0.1N
NaOH, using phenolphtalein as indicator.
Dornic degrees (°D))
))
)- mostly used in Netherlands and France
This value is obtained by titrating 100 mL of milk, diluted with 2 parts of distilled water, with N/9
NaOH, using phenolphtalein as indicator.
Percent lactic acid (%l.a.))
))
)- frequently used in the UK, USA, Canada, Australia and New Zeeland
This value is obtained in the same way as °D, dividing the result by 100.
The result can be easily converted into any of the other units as shown in the table below:
HS°hT°D°.a.l%
52.01.0111.01110.0
15.252.25220.0
4.019.0900.0
9/49/011 10.0

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SPECIFICATIONS
Titrator Range Titratable acidity (low range)
°SH: 0.0 to 15.0 °SH
°Th: 0 to 40 °Th
°D: 0 to 35 °D
%I.a.: 0.00 to 0.35 %I.a.
Titratable acidity (high range)
°SH: 10.0 to 75.0 °SH
°Th: 20 to 200 °Th
°D: 20 to 175 °D
%I.a.: 0.0 to 2.0 %I.a.
Resolution Titratable acidity (low range):
0.1 °SH
1 °Th
1 °D
0.01 %I.a.
Titratable acidity (high range):
0.5 °SH
1 °Th
1 °D
0.1 %I.a.
Accuracy 5% of reading
Titration method Acid-base titration
Principle End point titration, 8.30 pH
Pump debit 0.5 ml/min
Stirring speed 800 rpm
Log data Up to 50 samples
pH meter pH meter -2.0 to 16.0 pH / -2.00 to 16.00 pH
pH Resolution: 0.1 pH / 0.01 pH
pH Accuracy: ± 0.01 pH
pH Calibration: 1, 2 or 3 point calibration;
3 available buffers (4.01, 6.00, 8.30)
Temperature manual or automatic from
compensation: -20 to 120 °C (-4 to 248 °F)
Log data Up to 50 samples

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Temperature Range -20.0 to 120.0 °C (-4.0 to 248.0 °F)
Resolution 0.1 °C
Accuracy ±0.4 °C without probe error
REQUIRED REAGENTS
Code Description Quantity/Test
HI 84429-50 Titrant 0.5 mL
HI 84429-55 Standard 50 mL
Electrode FC 260B pH electrode (included)
HI 5315 reference electrode (included)
Temperature Probe HI 7662-M (included)
Environment 0 to 50 °C (32 to 122 °F); max 95% RH non-condensing
Power supply 12 Vdc power adapter
Dimensions 208 × 214 × 163 mm (8.2×8.4×6.4”) (with beaker)
Weight 2200 g (77 oz.)

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PRINCIPLE OF OPERATION
A neutralization titration is one where an acid and base react to form a neutral pH solution.
H++OH¯→H2O
A potentiometric acid-base titration employs an indicator electrode (such as a pH sensor) to establish
the equivalence point of the titration.
The accepted methodology for Titratable Acidity in dairy products employs a neutralization titration.
Acids (such as lactic acid) in the milk products react with a base (the titrant sodium hydroxide) to
produce water. When manually performed, the exact sample volume, titrant volume and titrant
concentration must be known. Additionally, the endpoint determination can be subjective when a
visual indicator (phenolphthalein) is utilized in an opaque or colored sample. Calculations are then
required. The entire procedure can be quite time consuming.
Titratable Acidity in dairy products, as performed on the HI 84429 minititrator, utilizes a simple
sample preparation, a high quality peristaltic dosing pump for titrant, potentiometric endpoint
detector and instantaneaous computations. To maintain the high precision of the titrator, a simple
pump calibration procedure is required. The calibration involves the analysis of a known volume of
a known solution (standard provided) and compensates for changes in pump dosing that may occur
due to many factors including tube stretching or aging. This procedure should be performed regularly.

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FUNCTIONAL DESCRIPTION
REAR PANEL
6. pH Electrode 10. Power adapter connector 14. Power switch
7. Temperature probe 11. Reference electrode socket 15. Peristaltic pump
8. Reference electrode 12. BNC electrode connector
9. Beaker 13. Temperature probe socket
FRONT PANEL
1. Titrant bottle 3. Keypad 5. Peristaltic pump tubes
2. Graphic LCD 4. Electrode holder

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KEYPAD FUNCTION AND INDICATORS
ESC - used to leave the current screen and to return either to the previous screen or to the
main screen, depending on the context, while pressed in SETUP the new value of
the set parameter is not changed.
/ - used to modify a parameter’s value, to scroll the information displayed while
viewing a help or to move between the options from the instrument’s SETUP
HELP - used to access/leave the instrument’s contextual help
MENU - used to enter Setup, Recall or GLP selection menu, while instrument is in pH or
Titration main screen
STIR - used to start/stop the stirrer.
Note: The stirrer starts automatically during pump calibration and titration and cannot be
stopped by pressing STIR key.

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1. Current time and instrument mode information (pH meter or Titrator)
2. pH electrode condition information
3. Main reading information
4. Instrument status information
5. Functional key area
6. Indicates that the displayed value can be changed using ARROW keys
7. Temperature reading display
8. pH temperature compensation mode (manual or Automatic)
9. Stirrer and reading status area
GUIDE TO INCDICATORS
During the instrument’s operation a set of information are displayed on the LCD.
Displayed icons:
Unstable reading.
Stirrer on.
Pump activity.
Parameter can be changed.
1
5
2
3
4
9
6
8
7

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PERISTALTIC PUMP
Peristaltic pumps are self priming. Liquid never contacts the pump components. The titrant tubing
is pressed along the rotating rollers of the pump. The rollers compress the tubing drawing titrant
along and out the titrator tip.
TITRATOR STARTUP
• Place the instrument on a flat table. Do not place the instrument in direct sun light.
• Connect the power adapter to the instrument.
• Turn the instrument ON using the power switch from the rear panel of the instrument.
• Set up the instrument. See the “Setup Configuration Menu” section for details.
• Prepare the electrodes and attach pH sensor and reference electrode to the instrument.
• Calibrate the pH electrode. At least a single point calibration in 8.30 pH buffer is necessary
for titration.
• Place the peristaltic pump tube on the pump. See the “Pump Tube Replacement” section for
the procedure.
• Remove the reagent bottle cap and replace the bottle cap with the tubes. Place the reagent
bottle in the appropriate place on the titrator top.
• Connect the tubes with the peristaltic pump (inlet tube is connected with the reagent bottle,
outlet tube is connected with the dosing tip).
• Purge line.
• Calibrate the pump.
• Select Low Range in “Acidity Titration” setup parameter.
• Prepare the sample.
• Run a titration and log sample results.

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Note: The milk sample size will change with these settings:
Select Low Range for dairy products in the 0 to 15 °SH range. Select High Range for dairy
product in the 10 to 75 °SH range. The titrant solution remains the same for either selection.
Acidity titration
SETUP CONFIGURATION MENU
Option: °SH, °Th, °D, % l.a.
Press the corresponding function key to change the
option.
Concentration unit
The titrator’s setup configuration menu may be accessed from the pH or titration screens by
pressing the MENU key, then Setup.
A list of setup parameters will be displayed with currently configured setting.
While in the setup menu it is possible to modify the instrument’s operation parameters. The
ARROW keys permit the user to scroll the setup parameters.
Press HELP to view the contextual help.
Press ESC to return to the main screen.
TINUegnaRwoL
)elpmasklimLm05(
egnaRhgiH
)elpmasklimLm01(
HS°0.51ot0.00.57ot0.01
HT°04ot0002ot02
D°53ot0571ot02
.a.l
%53.0ot00.00.2ot0.0
Option: Low Range, High Range.
From your knowledge of expected concentrations,
use the table below to determine which settings are
appropriate.
Press the corresponding function key to select the
new option.

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Use the ARROW keys in order to increase/decrease
the value.
Press Accept to confirm or ESC to return to the
setup menu without saving the new value.
pH resolution
Option: 0.1 or 0.01.
Press the displayed function key in order to change
the option.
Option: °C or °F.
Press the function key in order to change the option.
Temperature unit
Option: 0 to 8.
Press Modify to access the backlight value.
Backlight
Calibration timeout
Option: Disabled or 1 to 7 days.
This option is used to set the number of days
before the pH calibration expired warning message
is flagged.
Press Modify to access the calibration timeout
value modify parameter.

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Press / to highlight the value to be modified
(year, month, day, hour, minute or second). Use
the ARROW keys to change the value.
Press Accept to confirm the new value or ESC to
return to the setup.
This option is used to set the instrument’s date and
time.
Press Modify to change the date/time.
Date / Time
Contrast
Option: 0to 20.
This option is used to set the display’s contrast.
Press Modify to change the display’s contrast.
Use the ARROW keys or / in order to
increase/decrease the value.
Press Accept to confirm the value or ESC to return
to the setup menu.
Use the ARROW keys or / in order to
increase/decrease the displayed constrast.
Press Accept to confirm or ESC to return to the
setup menu.

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Press the corresponding function key to change the
option.
If the new selected language cannot be loaded, the
previously selected language will be reloaded.
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.
Language
Use the ARROW keys to select the desired format.
Press Accept to confirm the value or ESC to return
to the setup menu.
Date format
Press Modify to change the Date Format.
This option is used to enable/disable tutorial mode.
If enabled this option will provide the user short
guides on the screen.
Press the function key to select this option.
Tutorial
Option: AM/PM or 24 hours.
Press the functional key to select the new value.
Time format

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Press Select to view the firmware version, language
version, mV factory calibration date and time and
temperature factory calibration date and time.
Press ESC to return to the Setup mode.
Meter information
Press the function key to select the new option.
When enabled, a short beep is heard every time a
key is pressed or when the calibration can be
confirmed.
A long beep alert sounds when the pressed key is
not active or a wrong condition is detected while in
calibration.
Beep On

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ELECTRODE PREPARATION
PREPARATION PROCEDURE
Remove the electrode protective cap.
DO NOT BE ALARMED IF ANY SALT DEPOSITS ARE PRESENT. This is normal with electrodes and
they will disappear when rinsed with water.
During transport tiny bubbles of air may have formed inside the glass bulb. The electrode cannot
function properly under these conditions. These bubbles can be removed by "shaking down" the
electrode as you would do with a glass thermometer.
If the bulb is dry, soak the electrode in HI 70300 Storage Solution for at least one hour.
Preparation of reference electrode:
• Unwrap ParafilmTM seal found over ceramic junction
on inner stern of the reference electrod and discard.
This is only used for shipping.
• Rinse inner stern with deionized water making cer-
tain to wet o-ring found on the inner stern.
• Reassemble reference electrode by gently pushing
the inner assembly into the outer body, sliding spring
down cable, and screwing cap into place.
• Remove fill hole cover and o-ring or fill hole spout.
• Using the dropper pipette provided, add a few drops
of HI 7072 filling solution to the reference electrode,
wetting the o-ring and rinsing out the fill solution
chamber.
• Holding the body of the electrode depress the black cap with your thumb. This permits the
fill solution to drain out of the body. Verify if the electrode returns to its original position.
(You may need to gently assist for this to occur).
• Tighten the electrode cap onto the body and fill electrode body with HI 7072 filling solution
until fill solution volume is just below fill hole.
Note: During measurement always operate reference electrode with the fill hole open.
MEASUREMENT
Place pH electrode and reference electrode into electrode holder and connect the Cable
Connectors to the instrument.
Rinse the pH and reference electrodes tip with distilled or deionized water. Immerse the pH and
reference electrodes (bottom 4 cm /1½”) in the sample and stir gently for a few seconds.
For a faster response and to avoid cross-contamination of the samples, rinse the electrode tip
with a few drops of the solution to be tested, before taking measurements.

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ELECTRODE CALIBRATION PROCEDURE
It is recommended to calibrate the instrument frequently, especially if high accuracy is required.
The pH range should be recalibrated:
a) Whenever the pH electrode is replaced
b) At least once a week
c) After testing aggresive chemicals and after electrode is cleaned
d) When extreme accuracy is required
e) If the pH calibration expired warning is displayed during measurement. Every time
you calibrate the instrument use fresh buffers and perform an electrode Cleaning Procedure (see
page 41).
PROCEDURE
A single, two or three-point calibration can be performed, using the 3 buffers 4.01, 6.00 and
8.30 pH. For a single point calibration any of the three buffers may be used, but using 8.30 pH
is advised.
Note: The HI 84429 will not accept other pH buffers for calibration.
• Pour small quantities of selected buffer solutions into clean beakers. For accurate calibration
use two beakers for each buffer solution, the first one for rinsing the electrode and the second
one for calibration.
• Put a magnetic stir bar in each beaker with the calibration buffer solution.
• Remove the protective cap and rinse the electrodes with some of the buffer solution to be
used for the first calibration point.
• Put the first beaker with calibration buffer in the beaker holder.
• Place the electrode holder on the top of the beaker and secure it by turning clockwise.
• Immerse the pH and reference electrodes and the temperature probe approximately 2 cm
(0.8”) into the buffer paying attention not to touch the stir bar.
To select Electrode calibration screen follow the next steps:
• From pH meter screen press CAL function key then Electrode.
• From Titrator screen press CAL function key then Electrode.

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THREE POINT CALIBRATION
• From the pH meter/titrator calibration menu screen select the Electrode calibration option.
The electrode calibration screen will be displayed.
• The 6.00 buffer will be selected by default. If necessary press the ARROW keys in order to
select a different buffer value.
• The (unstable measurement) symbol will be shown on the display until the reading
becomes stable.
• When the reading is stable and close to the selected buffer, the (unstable measurement)
symbol will disappear and the CFM key will become active.
• Press CFM to confirm the calibration.
• The calibrated value will be shown on the display and the second expected buffer value will
be displayed.
• After the first calibration point has been confirmed, press STIR to stop stirring.
• Remove the electrode holder with electrodes from the top of the beaker.
• Place the second buffer into beaker and place in beaker holder. Rinse the electrodes in a
beaker containing the second buffer rinsing solution.
• Place the electrode holder (with electrodes) on the top of the beaker, lock cap by turning and
press STIR.
• If necessary press the ARROW keys in order to select a different buffer value.
• The (unstable measurement) symbol will be shown on the display until the reading
becomes stable.