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.