Hanna Instruments | HI84529,HI84529U | Owner Manual | Hanna Instruments HI84529U-01 Owner Manual

Hanna Instruments HI84529U-01 Owner Manual
Instruction Manual
HI 84529
TITRATABLE ACIDITY
MINITITRATOR & pH METER
for Dairy Products
w w w. h a n n a i n s t . c o m
1
Dear Customer,
Thank you for choosing a Hanna Instrument product.
Please read this instruction manual carefully before using this instrument. This manual will
provide you with the necessary information for correct use of this instrument, as well as a precise
idea of its versatility.
If you need additional technical information, do not hesitate to e-mail us at tech@hannainst.com
or view our worldwide contact list at www.hannainst.com.
TABLE OF CONTENTS
PRELIMINARY EXAMINATION................................................................................................. 3
GENERAL DESCRIPTION ........................................................................................................ 4
SIGNIFICANCE OF USE .......................................................................................................... 5
SPECIFICATIONS ................................................................................................................... 6
PRINCIPLE OF OPERATION .................................................................................................... 7
FUNCTIONAL DESCRIPTION ................................................................................................... 8
TITRATOR STARTUP ........................................................................................................... 10
SETUP MENU .................................................................................................................... 12
GUIDE TO DISPLAY CODES ................................................................................................... 16
ELECTRODE PREPARATION .................................................................................................. 20
ELECTRODE CALIBRATION PROCEDURE ................................................................................. 21
pH BUFFER TEMPERATURE DEPENDENCE ............................................................................ 25
DOSING PUMP INSTALLATION ............................................................................................. 26
DOSING PUMP PRIME PROCEDURE ..................................................................................... 26
PUMP CALIBRATION PROCEDURE ........................................................................................ 28
TITRATION PROCEDURE ..................................................................................................... 30
pH MEASUREMENT ............................................................................................................ 35
PC INTERFACE AND DATA TRANSFER ................................................................................... 38
TROUBLESHOOTING GUIDE ................................................................................................ 39
ELECTRODE CONDITIONING AND MAINTENANCE .................................................................. 41
ACCESSORIES ..................................................................................................................... 42
WARRANTY ........................................................................................................................ 43
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.
2
PRELIMINARY EXAMINATION
Please examine this product carefully. Make sure that the instrument is not damaged. If any
damage occurred during shipment, please notify your Dealer.
Each HI 84529 minititrator is supplied complete with:
• HI 84529-70 Reagent Kit for titratable acidity in dairy products
• FC 260B pH electrode
• HI 5315 Reference electrode
• HI 7662-M Temperature probe
• HI 7072 Fill solution (30 mL)
• HI 700640 Cleaning solution for milk deposits (2 x 20 mL)
• One capillary dropper pipette
• Two 100 mL beakers
• Tube set (aspiration tube with titrant bottle cap and dispensing tube with tip)
• Dosing Pump Valve
• 5 mL Syringe
• 1 mL Plastic Pipette
• Stir bar
• Power Adapter
• 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.
3
GENERAL DESCRIPTION
The HI 84529 is a low-cost easy to use, microprocessor-based automatic minititrator and pH meter
designed for the rapid and accurate analysis of Total Titratable Acidity in Dairy Products. The
HI 84529 will quickly become a valuable tool by eliminating subjective factors including color
indicators, errors in calculations or erratic titrant additions.
The instrument benefits from Hanna’s many years of experience as a manufacturer of quality
analytical instrumentation. A clear and well-designed user interface makes the instrument intuitive
and simple to use.
By pressing the Start key in Titrator mode, the instrument will automatically titrate the sample to
the set end point, perform all necessary calculations and display the results in the selected unit. At
the end of the titration, another titration can be started by pressing the Restart key.
A dedicated HELP keys aids in setup, calibration and troubleshooting.
Other features:
• pH meter / mV meter
• Stir speed control
• Graphic mode to display the titration data
• Data can be stored using the log feature and then exported to a USB stick or transferred to
a PC using the USB connection
• Log on demand for up to 400 samples (200 mV/pH measurements; 200 for titration
results)
• GLP feature, to view calibration data for the pH electrode and pump
4
SIGNIFICANCE OF USE
Titratable acidity can be expressed in several units; % lactic acid (% l.a.), degree Soxhlet Henkel
(°SH), degree Dornic (°D) or degree Thörner (°TH). Each of these units corresponds to a specific
procedure used to titrate dairy products.
Soxhlet Henkel degrees (°SH) - mostly used in Central Europe exept France and the Netherlands.
This value is a number of mL of 0.25N NaOH used for titration
of 100 mL milk, using phenolphtalein as indicator.
Thörner 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, with N/9 (0.11 N) NaOH, using
phenolphtalein as indicator.
Percent lactic acid (%l.a.) - frequently used in the UK, USA, Canada, Australia and New
Zealand. This value is obtained in the same way as °D, dividing
the result by 100.
The titratable acidity values will vary depending on the method used. Select Low 50 to titrate a non-diluted
sample, or select Low 20 / High 20 to titrate 20 mL or 20 g samples that are diluted with twice its
volume of deionized a distilled water. The HI 84529 uses methods based on AOAC International and
Standard Methods for the Examination of Dairy Products. Both of these method report titratable
acidity as % lactic acid, a rough conversion factor can be used to convert the results to the other
available units:
From: To:
Divide By:
%l.a. °SH
0.0225
%l.a.
°D
0.0100
%l.a. °TH
0.0090
The HI 84529 can be customized to meet the needs of any dairy analysis lab. Samples can be
titrated by weight or volume, diluted or non-diluted (low range only) and titrated to a fixed pH end
point that can be adjusted by the user.
5
SPECIFICATIONS
Titrator
Range
Low Range
%I.a.: 0.01 to 0.20
°SH: 0.4 to 8.9
°D: 1.0 to 20.0
°TH: 1.1 to 22.2
High Range
%I.a.: 0.1 to 2.0
°SH: 4.4 to 88.9
°D: 10 to 200
°TH: 11.1 to 222.2
Resolution %I.a.: 0.01 (Low Range) / 0.1 (High Range)
°SH: 0.1
°D: 0.1 (Low Range) / 1 (High Range)
°TH: 0.1
Accuracy
Low Range
± 0.01 %l.a. @ 25 °C
High Range
± 0.1 %l.a. @ 25 °C
Sample size
Low Range 20: 20 mL or 20 g
Low Range 50: 50 mL or 50 g
High Range 20: 20 mL or 20 g
Titration method Acid-base titration
Principle
End point titration
Pump speed
10 mL/min
Stirring speed
800 (Low Range) / 1000 (High Range)
Log data
Up to 200 samples
pH meter pH Range
-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;
4 available buffers (4.01, 6.00, 8.30, 10.01)
Temperature
Manual or automatic
Compensation
mV meter mV Range
-2000.0 to 2000.0 mV
mV Resolution 0.1 mV
mV Accuracy
± 1.0 mV
Log data
Up to 200 samples (pH or mV)
6
Temperature
Electrode
Temperature Probe
Environment
Power supply
Dimensions
Weight
Range
-20.0 to 120.0 °C (-4.0 to 248.0 °F)
Resolution
0.1 °C
Accuracy
±0.4 °C without probe error
FC 260B pH electrode
HI 5315 Reference electrode
HI 7662-M
0 to 50 °C (32 to 122 °F); max 95% RH non-condensing
12 Vdc power adapter
235 x 200 x 150 mm (9.2 x 7.9 x 5.9”)
1.9 kg (67.0 oz.)
REQUIRED REAGENTS
Code
HI 84529-50
HI 84529-51
HI 84529-52
HI 84529-55
Description
Titrant Low Range 20
Titrant High Range 20
Titrant Low Range 50
Pump Calibration Standard
PRINCIPLE OF OPERATION
The methodology for titratable acidity in dairy products is based on neutralization reaction where
the acids in the sample (i.e. lactic acid) reacts with a base (i.e. sodium hydroxide) to produce
water:
H++OH¯→H2O
In an ideal solution, the endpoint of an acid titration corresponds stoichiometrically to the complete
neutralization of the acids present.
This endpoint for this reaction can be determined visually using a color indicator (i.e. phenolphthalein),
however this endpoint becomes very objective in opaque and colored samples. The HI 84529
removes this issue by titrating to a fixed pH endpoint that can be set by the user. The HI 84529 can
be customized to meet individual needs with samples titrated by mass or by volume, in two different
ranges, with diluted and non-diluted (low range only). For precise analysis the sample size, volume
of titrant added and titrant concentration must be known.
The HI 84529 Titratable Acid in Dairy Products Minititrator utilizes a simple sample preparation,
a high quality dosing pump for titrant additions, potentiometric endpoint determination and
instantaneous computations. To maintain the high accuracy of the minititrator a simple pump
calibration is required. The pump calibration uses a known quantity of a known solution to
compensate for changes in the dosing system, this procedure should be performed regularly.
7
FUNCTIONAL DESCRIPTION
OVERHEAD VIEW
1)
2)
3)
4)
5)
Titrant bottle
Liquid Crystal Display (LCD)
Keypad
Electrode holder
Dispensing tube
FRONT VIEW
REAR VIEW
6) Aspiration tube
7) pH Electrode
8) Temperature probe
9) Reference electrode
10) Syringe
11) Electrode holder
12) Power switch
13) USB connector (PC interface)
14) USB connector (Storage interface)
15) Power adapter
16) BNC electrode connector
17) Temperature connector
18) Reference connector
19) Titrant bottle
20) Dosing Pump Valve
8
KEYPAD FUNCTION
ESC - used to leave the current screen and to return either to the previous screen or to the
main screen. In Setup, exits a parameter without changing the value.
/ - used to modify the parameters’ values, to scroll the information displayed while
viewing a help screen or to move between the options from the instrument’s Setup
CAL - used to access the Electrode and Pump calibration options
HELP - used to access/exit the instrument’s contextual help
LOG - used to save the current mV/pH reading in pH meter mode and the titration result
MENU - used to enter Setup, Recall or GLP selection menu, while instrument is in pH or
Titration mode
STIR - used to start/stop the stirrer
Note: The stirrer starts automatically during pump calibration and titration, it cannot
be stopped by pressing STIR key.
GUIDE TO INDICATORS
During the instrument’s operation a set of information are displayed on the LCD.
Displayed icons:
Stirrer on.
Pump running.
Unstable reading.
Stirrer is not working properly.
Parameter can be modified.
1) Current time and instrument mode information (pH meter or Titrator)
2) pH electrode condition
3) Instrument status
9
4)
5)
6)
7)
8)
Virtual option keys
Stirrer and reading status
Main reading information
pH temperature compensation mode (Manual or Automatic)
Temperature reading
DOSING PUMP
The dosing pump is based on a valve that automatically moves the titrant between the titrant
bottle and syringe when filling the syringe and between the syringe and sample when
dispensing. A replaceable 5 mL plastic syringe is used to limit the amount of titrant used per test
to ensure the highest possible accuracy. Before a set of titrations, it is necessary to prime the
dosing system.
Note: Once titrations have been completed, the dosing system should be cleaned with deionized
water using the prime feature.
TITRATOR STARTUP
This is a general outline of the steps required to perform a titration. The following topics are
expanded upon in each section that follows.
• 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 on the rear panel of the instrument.
• Set up the instrument. See the “Setup Menu” section for details.
• Connect the pH electrode to the instrument.
• Connect the reference electrode to the instrument.
• Connect the temperature probe to the instrument.
• Calibrate the pH electrode.
• Connect the tubes and the valve. See the “Dosing Pump Installation” section for the
procedure.
• Remove the titrant bottle cap and replace it with the bottle cap with tubes. Place the titrant
bottle in the appropriate place on the titrator top.
Note: Different titrants are required based on the concentration. See “Pump Calibration Procedure”
for details.
• Prime the syringe. To assure high accuracy, verify there are no air bubbles in the syringe or
tubing.
• Calibrate the pump.
10
Note: Different volumes of standards are required based on the concentration. See “Pump
Calibration Procedure” for details.
• Prepare the sample.
• Run a titration and log sample results.
SETUP MENU
The titrator’s setup menu may be accessed from the main screen (meter or titrator) 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.
Concentration Unit
% l.a., °SH, °D or °TH
Press the corresponding virtual option key to change
the option.
% l.a. - % lactic acid
°SH - °Soxhlet Henkel
°D - °Dornic
°TH - °Thörner
Acidity Titration
Low 20, Low 50 or High 20
Press the corresponding virtual option key to select
the desired range.
Note: Different titrants are required for each range.
Sample Type
Mass or Volume
Samples can be added by volume or by mass. For
improved accuracy all samples should be added by
mass.
11
Calibration Timeout
Disabled or 1 to 7 days
This option is used to set the number of days before
the pH calibration expired warning message is
displayed.
Press Modify to access the calibration timeout screen.
Use the ARROW keys to select the value.
Press Select to confirm or ESC to return to the setup
menu without saving the changes.
pH Resolution
0.1 or 0.01
Press the displayed virtual option key to change the
option.
Temperature Unit
°C, °F or K
Press the virtual option key to change the option.
Time
Press the Modify key to change the time and time
format.
Press Format to switch between 12 hour (am/pm)
and 24 hour mode.
Press to highlight the value to be modified. Use
the ARROW keys to change the value. Press Accept
to confirm the new value or ESC to return to the setup.
12
Date
Press the Modify key to change the date and date
format.
Press Format to cycle between the available date
formats.
Press to highlight the value to be modified. Use
the ARROW keys to change the value. Press Accept
to confirm the new value or ESC to return to the
setup.
Key Beep
Select Enable to activate or Disable to deactivate
the Key Beep function.
If enabled, a short beep will be heard every time a
key is pressed.
Error Beep
Select Enable to activate or Disable to deactivate
the Error Beep function.
If enabled, a beep will be heard when an error
condition occurs.
Decimal Separator
This option allows the user to select the symbol
used for a decimal separator.
13
LCD Contrast
This option is used to set the display’s contrast.
Press Modify to change the display’s contrast.
The default value is 8.
Use the ARROW keys or
/
to increase/
decrease the value.
Press Accept to confirm the value or ESC to return
to the setup menu.
LCD Backlight
Press Modify to change the backlight value.
The default value is 3.
Use the ARROW keys or
/
to increase/
decrease the backlight level.
Press Accept to confirm or ESC to return to the
setup menu.
pH endpoint
Press Modify to change the pH endpoint value.
The default value is 8.3 pH.
Use the ARROW keys to select the value.
Press Accept to confirm or ESC to return to the
setup menu without saving the changes.
14
Language
Tutorial
Press the corresponding virtual option key to change
the option. If the selected language cannot be
loaded, the previously selected language will be
reloaded. If no language can be loaded at startup,
the instrument will work in “safe mode”. In “safe
mode” all messages are displayed in English and
tutorial and help information are not available.
Enable or Disable the Tutorial. This helpful tool
offers additional information during calibration and
titration.
Meter Information
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 menu.
Restore Factory Settings
Press Select to restore the factory settings.
Press Yes to confirm the restore process or No to
return without restoring.
Press ESC to return to the setup menu.
15
GUIDE TO DISPLAY CODES
This screen appears when the instrument is turned
on during the initialization process.
Titration screen display.
Titration screen when a titration is in progress.
Prime burette screen.
Prime burette screen when the dosing system is
running.
This error message appears when the pump is not
working properly. Check the tubing, valve and
syringe. Press Restart to try again.
16
This screen appears when the titrator is in calibration
mode.
Press Pump to calibrate Pump.
Press Electrode to calibrate pH electrode.
PUMP CALIBRATION MESSAGES
Pump calibration is initiated by pressing the Start
key.
This screen appears while pump calibration is in
progress. Press ESC or Stop key to return to the
Pump Calibration screen.
This error message appears during pump calibration
when the end point can not be reached and the
maximum amount of titrant is exceeded. Check
standard, electrode and/or dosing system and try
again.
The calibration was outside the acceptable limits.
Prepare a new standard and try again.
This error message appears when the pH reading
exceeds the acceptable input limits (-2.00 < pH
> 16.00).
17
This screen appears when the stirrer is not working
properly. Check the stir bar and beaker content.
Press Restart to try again.
This error message appears when the pump is not
working properly. Check the tubing, valve and
syringe. Press Restart to try again.
pH CALIBRATION MESSAGES
pH calibration mode.
When the reading has stabilized, press Confirm to
accept the calibration or Clear to restore the default
calibration.
The “Wrong Buffer” message is displayed when the
pH value is outside of the acceptable range. Clean the
electrode by following the Cleaning Procedure and/or
check the buffer concentration before continuing the
pH calibration.
Press the ESC key to exit pH calibration mode.
TITRATION MESSAGES
This screen is displayed when the instrument is in
titration mode. Press Start to begin a titration, Meter
to enter pH meter mode or Prime to enter into the
prime function.
18
The titration result, expressed as concentration in
selected unit, is displayed automatically at the end
of the titration. Press Restart to start another titration
or ESC to return to the main screen.
This error message appears when the input reading
(pH or temperature) exceeds the specified limits.
The pH or temperature value and concentration
will blink indicating an error.
This screen appears when the sample concentration
is out of range.
This screen appears when the stirrer is not working
properly. Check the stir bar and beaker content.
Press Restart to try again.
This error message appears when the pump is not
working properly. Check the tubing, valve and
syringe. Press Restart to try again.
19
ELECTRODE PREPARATION
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 distilled/deionized 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 electrode and discard. This
is only used for shipping.
• Rinse inner stern with deionized water, making certain
to wet o-ring found on the inner stern.
• Reassemble reference electrode by gently pushing the
inner assembly into the outer body (from the bottom),
slide spring and cap down the cable and over the top of
the inner stern. Screw the cap into place.
• Unscrew and remove the fill hole plug and o-ring on fill
hole spout.
• Using the dropper pipette provided, add a few drops of
HI 7072 fill solution to the electrode. Invert electrode
to wet the o-ring and rinse the electrolyte chamber.
• Holding the body of the electrode gently press the cap with your thumb. This permits the fill
solution to drain out of the body. Release your thumb and verify electrode returns to its
original position (you may need to gently assist for this to occur).
• Fill electrode body with HI 7072 fill solution until 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 electrodes to
the instrument.
Rinse the pH and reference electrodes with distilled or deionized water. Immerse the pH and
reference electrodes 1.5 cm (0.6”) in the sample and stir gently for a few seconds.
For a faster response and to avoid cross-contamination of the samples, rinse the electrodes with
a few drops of the solution to be tested, before taking measurements.
20
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, but daily is advised
c) After testing aggressive chemicals and after the electrode is cleaned
d) When high accuracy is required
e) If the pH calibration expired warning is displayed during measurement
Every time you calibrate the instrument use fresh buffers and clean the electrode (see page 41).
PROCEDURE
A single one, two or three-point calibration can be performed, using four predefined buffers
4.01, 6.00, 8.30 and 10.01 pH. For a single point calibration any of the four buffers may be
used, 8.30 pH is recommended.
Note: The HI 84529 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 the beaker that will be used for calibration.
• Remove the protective cap and rinse the electrode 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 and
press STIR.
• Immerse the pH electrode, reference electrode and temperature probe approximately 1.5 cm
(0.6”) into the buffer, paying attention not to touch the stir bar.
To enter Electrode Calibration follow the next steps:
• Press CAL key then Electrode.
• The electrode calibration screen will be displayed.
• Press Clear to delete the previous calibration.
1 Point calibration
• The 8.30 buffer will be selected by default. If necessary press the ARROW keys in order to
select a different buffer value.
21
• 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 Confirm key will become active.
• Press Confirm to confirm the calibration or ESC to exit calibration.
• After the first calibration point has been confirmed, press ESC to exit without performing the
second calibration point.
2 Point calibration
• The calibrated value will be shown on the display and the second expected buffer value will
be displayed.
• Remove the electrode holder with electrodes from the top of the beaker.
• Place the second beaker with calibration buffer in the 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 and secure it by turning
clockwise and press STIR.
• If necessary, press the ARROW keys in order to select a different buffer value.
22
• 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 Confirm key will become active.
• Press Confirm to confirm the calibration.
• The calibrated value will be shown on the display and the third expected buffer value will be
automatically selected.
• After the second calibration point has been confirmed, press ESC to exit without performing
the third calibration point.
3 Point calibration
• Remove the electrode holder with electrodes from the top of the beaker.
• Place the third beaker with calibration buffer in the beaker holder. Rinse the electrodes in a
beaker containing the third buffer rinsing solution.
• Place the electrode holder (with electrodes) on the top of the beaker and secure it by turning
clockwise 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.
• When the reading is stable and close to the selected buffer, the (unstable measurement)
symbol will disappear and the Confirm key will become active.
• Press Confirm to confirm the calibration. The instrument stores the calibration value and
returns to calibration menu, where the date and time for the pH calibration will be updated.
Note:
• A buffer confirmed during the calibration process is removed from the list of available buffers.
• If the value measured by the instrument is not close to the selected buffer, a “Wrong Buffer”
error message will be shown on the display.
Check if the correct buffer has been used or regenerate the pH electrodes by following the
Cleaning Procedure (see page 41). If necessary change the buffer or the electrode.
23
• If the measured offset isn’t within the preset limits (±45 mV), the meter will display the
message “Buffer Contaminated” alternatively with ”Electrode Dirty/Broken”.
• If the computed slope isn’t within the preset limits, the meter will display the message
“Wrong Slope”. If the slope is too high the symbol
will be displayed. If the slope is
too low the symbol
will be displayed.
• If the “Wrong Old Slope” error message is displayed, an inconsistency exists between the
current and the previous (old) calibration. Clear the previous calibration by pressing Clear and
proceed with calibration from the current calibration point. The instrument will keep all the
confirmed values during the current calibration.
• If the temperature reading is out of the defined temperature range of the buffer (0 to 45 °C),
the “Wrong Buffer Temperature” error message will be displayed, and the temperature
symbol will blink on the display. Calibration cannot be confirmed in this situation.
24
Note: • To clear a previous calibration and to return to the default value, press Clear at any
time after entering calibration mode. If Clear is invoked during the first calibration
point the instrument returns to the measurement mode.
• The Clear key is displayed only if a previous calibration exists.
pH BUFFER TEMPERATURE DEPENDENCE
Temperature has an effect on pH. The calibration buffer solutions are affected by temperature
changes to a lesser degree than normal solutions. During calibration, the instrument will
automatically calibrate to the pH value corresponding to the measured or set temperature.
TEMP
pH BUFFERS
ºC
ºF
4.01
6. 00
8.30
10.01
0
32
4.01
6.12
8.48
10.32
5
41
4.00
6.09
8.44
10.24
10
50
4.00
6.06
8.41
10.18
15
59
4.00
6.04
8.37
10.12
20
68
4.00
6.02
8.33
10.06
25
77
4.01
6.00
8.30
10.01
30
86
4.02
5.99
8.27
9.96
35
95
4.03
5.98
8.24
9.92
40
104
4.04
5.97
8.21
9.88
45
113
4.05
5.97
8.18
9.85
During calibration the instrument will display the pH buffer value at 25 ºC.
25
DOSING PUMP INSTALLATION
To install the dosing pump follow the procedure below:
• Extend the plunger on the 5 mL syringe to its maximum volume.
• Place the syringe in the dedicated spot on the top of the meter (1).
• Arrange the bottom of the syringe into the holder on the pump (2). Once the syringe is in place
lower the barrel until it sits flush on the holder.
• Put the o-ring and syringe-fixing nut over the syringe (3) and turn clockwise to secure it in place (4).
• Place the valve on the top of the syringe (5). Ensure it fits securely.
• Insert the aspiration tube into the left side of the valve (6) and replace the titrant bottle cap with
the attached cap (7).
• Insert the dispensing tube into the top of the valve (8).
DOSING PUMP PRIME PROCEDURE
Prime cycle should be performed:
• if you notice there is no titrant in the tip
• whenever the dosing system tubes are replaced
• whenever a new bottle of titrant is used
• before starting a pump calibration
• before starting a series of titrations
The prime cycle is used to fill the syringe before starting a set of titrations.
Two rinse cycles of the syringe are shown in the figure below. The dispensing tube is connected to
the top of the valve and the aspiration tube on the left side.
26
Note: • The aspiration tube must be inserted in the
titrant bottle. The dosing tip must be placed
over a rinse beaker.
• Before starting the prime procedure, make
sure you are using the appropriate titrant
solution for the selected range.
• To prime the burette, select Prime option from Titration mode.
• Adjust the rinses number by pressing the and keys and press Start.
• The number of syringe rinses can be set between 1 and 5 (at least three rinses are recommended
to ensure that the air bubbles are completely removed).
• To pause the prime process press the Pause key; to continue press the Continue key. To stop the
prime process press the Stop key.
Note: This error message appears when the pump is not working properly. Check the tubing, valve
and syringe. Press Restart to try again.
27
PUMP CALIBRATION PROCEDURE
The calibration of the pump must be performed every time the syringe, pump tubing, the titrant
bottle or the pH electrode is changed. A pump calibration is recommended before each set of
titrations, after the titrator is left idle for several hours, or once daily.
Note: A pump calibration needs to be done in the desired range and sample size. Pump calibration
is independent of the sample type.
• Press MENU, select Setup and select the corresponding range according to the table below:
U NI T
Low Range 20 or 50 High Range 20
%l.a.
0.01 to 0.20
0.1 to 2.0
°SH
0.4 to 8.9
4.4 to 88.9
°D
1.0 to 20.0
10 to 200
°TH
1.1 to 22.2
11.1 to 222.2
• Verify the electrode has been calibrated in 8.30 pH buffer.
• Ensure the pump is primed with the correct titrant for the selected range (HI 84529-50 Low
Range 20 Titrant or HI 84529-52 Low Range 50 Titrant, HI 84529-51 High Range 20 Titrant).
Sample preparation: Use a clean pipette add a precisely measured amount of HI 84529-55
Calibration Standard to a clean beaker as indicated below:
Low Range 20 - 1 mL
Low Range 50 - 2 mL
High Range 20 - 10 mL
Note: Failure to use a clean pipette will result in erroneous
readings.
• Fill the beaker up to the 50 mL mark with the distilled or
deionized water.
• Press CAL key. The instrument displays the date and time of
the last electrode calibration, and the last pump calibration
for the selected range.
• Press Pump key.
Note: DO NOT PLACE THE TIP INTO THE
CALIBRATION BEAKER, PLACE THE TIP
OVER A WASTE BEAKER. A SMALL AMOUNT
OF TITRANT IS DISPENSED WHEN THE
PUMP RESETS.
• Press Start, wait for the syringe to refill.
• Place the stir bar in the beaker and put the beaker in
the minititrator top.
28
• Place the probe holder on the top of the beaker and secure it by turning clockwise.
• Rinse the pH electrode, reference electrode and temperature probe with deionized water and
immerse them roughly 1.5 cm (0.6”) into the sample. Be
sure that the tip of the electrode is not hitting the stir bar. If
necessary, additional distilled or deionized water can be added.
• Insert the dosing tip into the titrant tube sleeve. IT IS
CRITICAL THAT THE TIP BE IMMERSED APPROXIMATELY
0.25 CM (0.1") INTO THE SOLUTION BEING TITRATED.
• Press Continue to begin the calibration and Stop to abort it.
• At the end of the calibration, ”Calibration Completed“
appears on display. To repeat the calibration press Restart
or ESC to return to the main screen.
Note: • If temperature probe is not connected, Manual Temperature Compensation is used
and MTC appears on the right side of the screen. If Automatic Temperature
Compensation is in use the ATC appears on the right side of the screen.
• If an erroneous situation is encountered during the
calibration, an error message is displayed and the
calibration can be restarted by pressing Restart.
Prepare a new standard, rinse the electrode,
temperature probe and dosing tip and try again.
• If the calibration doesn’t complete and the max
titrant volume of titrant is reached, an error message
will be displayed. The calibration can be restarted
by pressing Restart. Prepare a new standard, rinse
electrode, temperature probe and dosing tip and
try again.
• This error message appears when the pH reading
exceeds the acceptable input limits (-2.00 < pH
> 16.00).
• This screen appears when the stirrer is not working
properly. Check the stir bar and beaker content.
Press Restart to try again.
• This error message appears when the pump is not
working properly. Check the tubing, valve and
syringe. Press Restart to try again.
29
TITRATION PROCEDURE
Note: Verify that the instrument has been calibrated (pH and pump) before performing any
titrations.
• Refer to “Setup Menu” (see page 12) to set up the instrument for your measurement.
• Select the corresponding measurement range: Low 20, Low 50 or High 20.
• Select the corresponding titration type: by volume or by mass.
• Ensure the pump is primed with the correct titrant for the selected range (HI 84529-50 Low
Range 20 Titrant or HI 84529-51 High Range 20 Titrant or HI 84529-52 Low Range 50
Titrant).
U NI T
Low Range 20
High Range 50
Low Range 50
%l.a.
0.01 to 0.20
0.1 to 2.0
°SH
0.4 to 8.9
4.4 to 88.9
°D
1.0 to 20.0
10 to 200
°TH
1.1 to 22.2
11.1 to 222.2
By Mass:
• Place a clean 100 mL plastic beaker on an analytical balance. Zero the balance.
• Add 20 ± 1 g (Low 20, High 20) or 50 ± 1 g (Low 50) to the beaker.
• Record the reading once it has stabilized.
• Remove the beaker from the balance.
By Volume:
• Volumetrically add 20 mL( Low 20, High 20) or 50 mL
(Low 50) to a clean 100mL plastic beaker.
Note: Failure to use a clean pipette will result in
erroneous readings.
Note: DO NOT PLACE THE TIP INTO THE SAMPLE
BEAKER. PLACE THE TIP OVER A WASTE
BEAKER. A SMALL AMOUNT OF TITRANT IS
DISPENSED WHEN THE PUMP RESETS.
• Press Start to begin a titration.
30
• For samples by mass the “Edit Sample Mass” screen will be displayed. Use the ARROW keys
to enter the exact sample mass then press Accept.
•
•
•
•
For 20 g and 20 mL samples add deionized or distilled water to the 60 mL mark.
Place the stir bar in the beaker and put the beaker in the minititrator top.
Place the probe holder on the top of the beaker and secure it by turning clockwise.
Rinse the pH electrode, reference electrode and temperature probe with
deionized water and immerse it roughly 1.5 cm (0.6”) into the sample.
Be sure that the tip of the electrode is not hitting the stir bar.
• Insert the dosing tip into the titrant tube sleeve. IT IS CRITICAL THAT THE
TIP BE IMMERSED APPROXIMATELY 0.25 CM (0.1") INTO THE SOLUTION
BEING TITRATED.
• Press Continue to begin the titration and Stop to abort it.
• The instrument will continuously update the concentration on the display. The value will be
displayed blinking. When the reading is under range “----” symbol appears blinking.
• The titration curve can be visualized during a titration by pressing Plot ON. Press Plot OFF or
ESC to exit this mode.
31
• At the end of the titration, the concentration is displayed in the selected unit. The titration curve
can be viewed by pressing Plot ON. Press Plot OFF or ESC to exit this mode.
• Press LOG to record the concentration value and
the titration curve into the instrument’s memory. A
message will be displayed for a few seconds
indicating the amount of free log space. Up to 200
log samples can be recorded in the instrument’s
memory.
• Press Restart to begin a new titration or ESC to
return to the titration menu.
• If the concentration exceeds the range limits (>0.01
%l.a. for Low Range, >2.0 %l.a. for High
Range), the exceeded range limit will be displayed
blinking. Another titration can be started by pressing
Restart.
• “Wrong input” error message appears when the
input reading (pH, temperature) exceeds the
specified limits. The pH or temperature value and
the concentration will blink indicating an error.
• This screen appears when the stirrer is not working
properly. Check the stir bar and beaker content.
Press Restart to try again.
• This error message appears when the pump is not
working properly. Check the tubing, valve and
syringe. Press Restart to try again.
32
TIPS FOR AN ACCURATE MEASUREMENT
The instructions listed below should be followed carefully to ensure measurements are conducted
with the highest possible accuracy and precision.
• IT IS CRITICAL THAT THE TIP BE IMMERSED IN THE SOLUTION BEING TITRATED
(APPROXIMATELY 0.25 CM).
• Calibrate the pump prior to each series of titrations.
• Calibrate the pump if the meter is left idle for several hours.
• Analyze the sample immediately after it is obtained.
• Clean the electrode with HI 70640 cleaning solutions specially designed for milk industry.
VIEW/DELETE TITRATOR RECORDED DATA
Press MENU then Recall to access the Titrator logs.
When an external USB storage device is connected, the Export key is displayed. It saves the
meter and titrator logs in two text format files on the storage device.
Press Meter or Titrator to view the respective logs.
The instrument will display a list of all the records stored in the log.
Use the ARROW keys to scroll the stored records list.
If the saved concentration was out of range, the “<” or “>” symbols are displayed in front
of the reading.
Press Delete to delete the selected record from the memory.
Press Del.All to delete all records.
Press Info to see detailed information about the highlighted record.
The selected record data and the titration curve data file name are displayed.
33
When a USB storage device is connected, the Export key is displayed. It saves the titration curve
data as a text file on the storage device using the displayed file name.
Use the ARROW keys when is displayed to scroll between the log records.
Press ESC to return to the previous screen.
Press Plot to visualize the titration curve or ESC to return to the previous screen. On the titration
curve, the end point volume and pH are displayed. The titration data (Total Titrant Volume on the
x-axis and pH on the y-axis) can be scanned through with the dotted line by using the ARROW keys.
To zoom on the titration curve press Zoom.
If Delete or Del.All is pressed the instrument will ask for confirmation.
Press Yes to delete the record or No to return to the previous screen.
Deleting a single record will renumber the list of records.
If the titrator log is empty, the message “No records available!” will be displayed.
34
TITRATOR GLP INFORMATION
Press MENU then GLP.
From this screen it is possible to select the Electrode
or the Pump GLP.
Press Pump to view the pump’s last calibration
time, date and slope for the selected range.
If a calibration hasn’t been performed, the message
“Not Calibrated” will be displayed.
pH MEASUREMENT
The HI 84529 can be used as a pH meter for direct measurements.
Verify that the instrument has been calibrated before taking pH measurements. Set the
instrument to pH meter. From titrator mode press Meter until pH units are displayed.
If an electrode calibration hasn’t been performed, or the number of days exceeds the calibration
time out value set, the message “CAL DUE” will blink on the left side of the display (see
Calibration timeout option in Setup for details).
If CAL DUE is displayed perform an electrode
calibration.
Press MENU to access the instrument’s menu.
Press HELP to view the contextual help, whenever
you need additional information.
Press STIR to start/stop the stirrer.
Press Titrator to enter titration mode.
Press CAL to access the calibration menu.
35
Press LOG to save the current reading. A message indicating the free log space will be
displayed for a few seconds.
In order to take pH measurements, follow the next steps:
• Submerge the tip of the electrode (4 cm/1 1/2’’) and the temperature probe into the sample
to be tested and stir gently. Allow time for the electrode to stabilize. When the reading
becomes stable, the
(unstable measurement) symbol will disappear.
• If the pH reading is less than -2.00 pH or greater than 16.00 pH, the closest full-scale
value will be displayed blinking.
If measurements are taken successively in different samples, it is recommended to rinse the
electrodes thoroughly with deionized or distilled water and then with some of the next sample
to prevent cross-contamination.
The pH reading is affected by temperature. In order to have accurate pH measurements, the
temperature effect must be compensated for. To use the Automatic Temperature Compensation
(ATC) feature, connect and submerge the HI 7662-M temperature probe into the sample as
close as possible to the electrode and wait for a few seconds. The “ATC” message will be
shown on the display. Automatic Temperature Compensation will provide pH corrected values for
the measured temperature. If Manual Temperature Compensation (MTC) is desired, the
temperature probe must be disconnected from the instrument.
The default temperature of 25 °C (77 °F) or the last temperature reading will be displayed,
preceded by the symbol and the “MTC” message.
The temperature can be adjusted with the ARROW keys (from -20.0 to 120.0 °C).
36
VIEW/DELETE RECORDED pH DATA
Press MENU key while in pH meter screen then Recall to access the meter logs.
When an external USB storage device is connected, the Export key is displayed. It saves the
meter and titrator logs in two text format files on the storage device.
Press Meter or Titrator to view the respective logs.
A list of records is stored in the pH log.
If the saved mV/pH measurements are out of range, the “<“ or “>” symbols are displayed in front
of the reading.
Use the ARROW keys to scroll the list of records.
Press Delete to delete the selected record.
Press Del.All to delete all the records.
Press Info to see detailed information about highlighted record.
Use ARROW keys when
is displayed to scroll between the records.
Press ESC to return to the previous screen.
If Delete or Del.All is pressed the instrument will ask for confirmation.
Press Yes to delete the record or No to return to the previous screen without deleting.
Deleting a single record will renumber the list of records.
37
If the pH log is empty, the message “No records available!” will be displayed.
pH METER GLP INFORMATION
The pH meter GLP screen displays the pH calibration data.
To view this information press MENU key while in pH meter mode then GLP.
Press Electrode to view information regarding electrode calibration.
The following items are included in electrode GLP: the time and date of the last calibration,
offset, slope, electrode condition, calibration timeout and the calibration buffers. The buffers
displayed in video inverse mode are from the previous calibration.
If a calibration hasn’t been performed, the message “Not Calibrated” will be displayed.
PC INTERFACE AND DATA TRANSFER
Data stored on the meter with the LOG function during pH/mV measurement and titrations can
be transferred from the meter to a USB stick using the Export function from the log recall menu.
Two text files are transferred on the USB stick. These files can be used for further analysis on a PC.
The logged data can also be transferred from the instrument to the PC using a USB cable.
Connect the USB cable and the following screen will be displayed.
38
Press Meter to generate the text file with Meter log data.
Press Titrator to generate the text file with Titrator log data.
Press Plot to generate the text files with Titration Plots.
The generated files are now visible and can be used for further analysis.
If the instrument has no logged Meter or Titrator records, the PC connected screen is displayed.
TROUBLESHOOTING GUIDE
SYMPTOMS
PROBLEM
D irty pH or reference
Slow response/excessive drift.
electrode.
SOLUTION
Soak the electrode tip HI 70640 solution
for 30 minutes and follow the cleaning
procedure. Refill reference electrode with
new fill solution.
Clogged/dirty junction.
Low electrolyte level
(reference electrode).
Cable connection.
Clean the pH electrode. Refill reference
electrode with fresh fill solution.
Check cable connection to meter and verify
protective cap is off.
While in pH reading mode,
-2.00 or 16.00 pH is
displayed blinking.
Reading out of range.
Check cable connection to meter and verify
protective cap is off.
Check the quality of the sample. Clean the
electrodes. Refill with fresh fill solution.
The meter does not accept
the pH buffer solution for
calibration.
Broken pH or reference
electrode.
Follow the electrode cleaning procedure. If
the error persists replace the electrode or
contact the vendor.
The pump calibration can't
be performed.
Broken pump tubing.
Wrong or
contaminated pump
calibration solution.
Broken pH electrodes.
Verify tubing, valve, syringe are intact
and solution passes when pump is primed
and no air bubbles are present. Check the
pump calibration solution. Verify electrodes
are calibrated. Prepare another standard,
prime the pump and restart the
calibration.
Reading fluctuates up and
down (noise).
39
SYMPTOMS
PROBLEM
SOLUTION
The temperature probe is
connected, but the meter
displays "MTC".
Broken temperature
probe.
Replace temperature probe.
After a titration the following
is displayed blinking:
Low Range: 0.20 %I.a., 8.9
°SH, 20.0 °D or 22.2 °TH.
High Range: 0.1 %l.a., 4.4
°SH, 10 °D or 11.1 °TH.
Broken electrode.
Instrument not
calibrated. Wrong
sample.
Concentration out of
range.
Check/clean the electrodes. Recalibrate the
instrument (pump and pH). Use care
during sample preparation. Check sample
size and permitted range.
At startup, the meter
displays the HANNA logo
permanently.
One of the keys is
stuck.
Check the keyboard or contact the vendor.
"Error xx" message is
displayed.
Internal error.
Power off the meter and then power it on
again. If the error persists, contact the
vendor.
"St irrer error" message is
Check the stir bar and
If the error persists, contact the vendor.
displayed at the end of
beaker content.
pump calibration or titration.
Non-spinning stirrer icon
blinking in pH calibration
and meter mode.
Check the stir bar and
If the error persists, contact the vendor.
beaker content.
"Pump error" message is
displayed.
Check the tubing,
valve and syringe.
At startup the meter displays The method file was
"Methods corrupted".
corrupted.
40
If the error persists, contact the vendor.
Contact the vendor.
ELECTRODE CONDITIONING AND MAINTENANCE
STORAGE PROCEDURE
To assure a quick response time, the glass bulb should be kept moist and not allowed to dry out.
Replace the solution in the protective cap with a few drops of HI 70300 or HI 80300 Storage
Solution. The HI 5313 Reference may be stored with its black cap and Fill hole covered. Rinse
and refill before using. Follow the Preparation Procedure on page 20 before taking measurements.
Note: NEVER STORE THE pH ELECTRODE IN DISTILLED OR DEIONIZED WATER.
PERIODIC MAINTENANCE
Inspect the electrodes and the cables. The cable used for connection to the instrument must be
intact and there must be no points of broken insulation on the cable or cracks on the electrode
stem or bulb. Connectors must be perfectly clean and dry. If any scratches or cracks are present,
replace the electrode. Rinse off any salt deposits with distilled/deionized water.
pH CLEANING PROCEDURE
• General
Soak in Hanna HI 7061 or HI 8061 General Cleaning Solution for
approximately ½ hour.
Soak in Hanna HI 70640 Cleaning Solution for milk deposits for
• Milk deposits
approximately ½ hour (pH half cell only).
• Protein
Soak in Hanna HI 7073 or HI 8073 Protein Cleaning Solution for
15 minutes.
IMPORTANT: After performing any of the cleaning procedures, rinse the electrode thoroughly
with distilled or deionized water and soak the electrode in HI 70300 or HI 80300 Storage
Solution for at least 1 hour before taking measurements.
REFERENCE ELECTRODE CLEANING
• Drain the old fill solution, rinse with a few drops of HI 7072 solution, drain, then refill with
HI 7072 solution.
• Do not use an electrode if crystallized salts are visible inside the electrode. Drain electrode,
disassemble and rinse internal body with deionized water. Reassemble and refill with fresh
fill solution.
• The internal chamber of this electrode is gell filled. If the electrode has been left dry for long
periods of time the gel may be dehydrated and stable measurements may not be obtainable.
Disassemble electrode and soak internal assembly in HI 7072 fill solution. Verify the
ceramic is wetted by the fill solution. Warming the solution slightly (50 °C) before soaking
will hasten this process. Permit the electrode to cool completely while immersed in this
solution.
41
ACCESSORIES
REAGENTS
HI 84529-50
Titrant solution for Low Range 20 (120 ml)
HI 84529-51
Titrant solution for High Range 20 (120 ml)
HI 84529-52
Titrant solution for Low Range 50 (120 ml)
HI 84529-55
Pump Calibration Standard (230 mL)
pH CALIBRATION SOLUTIONS
HI 7004M
Buffer solution pH 4.01 (230 mL)
HI 70060M
Buffer solution pH 6.00 (230 mL)
HI 70083M
Buffer solution pH 8.30 (230 mL)
HI 7010M
Buffer solution pH 10.01 (230 mL)
ELECTRODES
FC 260B
pH electrode
HI 5315
Reference electrode
HI 7662-M
Temperature probe
ELECTRODE FILL SOLUTION
HI 7072
Reference electrode fill solution (4 x 30 mL)
ELECTRODE STORAGE SOLUTION
HI 70300L
Storage Solution, 500 mL bottle
CLEANING SOLUTIONS
HI 70640L
Cleaning solution for remaining milk deposits (500 mL)
HI 70641L
Cleaning and disinfecting for dairy products (500 mL)
HI 70642L
Cleaning solution for remaining cheese deposits (500 mL)
HI 7077L
Electrode cleaning solution for oils (500 mL)
OTHER ACCESSORIES
HI 70500
Tube set with cap for titrant bottle, tip and valve
HI 71005/8
115 Vac to 12 Vdc, 800 mA
HI 71006/8
230 Vac to 12 Vdc, 800 mA
HI 731319
Stir bar (10 pcs., 25 x 7 mm)
HI 740036P
100 mL plastic beaker (10 pcs.)
HI 740037P
20 mL plastic beaker (10 pcs.)
HI 740236
5 mL Syringe for minititrator
HI 920013
PC Connection Cable
42
WARRANTY
HI 84529 is guaranteed for two years against defects in workmanship and materials when used
for it’s intended purpose and maintained according to instructions. Electrodes and probes are
guaranteed for six months. This warranty is limited to repair or replacement free of charge.
Damage due to accidents, misuse, tampering or lack of prescribed maintenance is not covered.
If service is required, contact your dealer from whom you purchased the instrument. If under
warranty, report the model number, date of purchase, serial number and the nature of the
problem. If the repair is not covered by the warranty, you will be notified of the charges incurred.
If the instrument is to be returned to Hanna Instruments, first obtain a Returned Goods
Authorization number from the Technical Service department and then send it with shipping costs
prepaid. When shipping any instrument, make sure it is properly packed for complete protection.
To validate your warranty, fill out and return the enclosed warranty card within 14 days from the
date of purchase.
RECOMMENDATION FOR USERS
Before using this product, make sure that it is entirely suitable for your specific application and for the
environment in which it is used.
Operation of this instrument may cause unacceptable interferences to other electronic equipment, thus
requiring the operator to take all necessary steps to correct interferences.
Any variation introduced by the user to the supplied equipment may degrade the instrument’s EMC
performance.
To avoid damages or burns, do not put the instrument in microwave ovens. For your and the instrument’s
safety, do not use or store the instrument in hazardous environments.
Hanna Instruments reserves the right to modify the design, construction or appearance of its products
without advance notice.
43
Hanna Instruments Inc.
Highland Industrial Park
584 Park East Drive
Woonsocket, RI 02895 USA
Technical Support for Customers
Tel. (800) 426 6287
Fax (401) 765 7575
E-mail tech@hannainst.com
www.hannainst.com
Local Sales and Customer Service Office
Printed in ROMANIA
MAN84529 10/14
44
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