Hanna Instruments HI 9126 User manual

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Instruction Manual
HI9126
Calibration Check
Waterproof
pH/mV/°C Meter
www.hannainst.com

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Dear Customer,
Thank you for choosing a Hanna Instruments product.
Please read this instruction manual carefully before using the instrument.
This manual will provide you with the necessary information for correct
use of the instrument, as well as a precise idea of its versatility.
If you need additional technical information, do not hesitate to e‑mail
us at [email protected] or view our worldwide contact list at
www.hannainst.com.
PRELIMINARY EXAMINATION .........................................................3
GENERAL DESCRIPTION..................................................................3
FUNCTIONAL DESCRIPTION.............................................................4
SPECIFICATIONS............................................................................5
OPERATIONAL GUIDE.....................................................................6
pH CALIBRATION .........................................................................10
pH BUFFER TEMPERATURE DEPENDENCE ......................................15
SETUP MENU..............................................................................16
mV CALIBRATION.........................................................................18
TEMPERATURE CALIBRATION........................................................18
BATTERIES REPLACEMENT............................................................19
LCD MESSAGE GUIDE...................................................................21
TEMPERATURE CORRELATION FOR pH SENSITIVE GLASS.................22
ELECTRODE CONDITIONING & MAINTENANCE.................................23
TROUBLESHOOTING GUIDE ..........................................................25
ACCESSORIES..............................................................................26
TABLE OF CONTENTS

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GENERAL DESCRIPTION
HI9126 is a state‑of‑the‑art waterproof, heavy‑duty pH meter designed
to provide laboratory results and accuracy under harsh industrial
conditions.
A large multil‑level LCD, with clear indications related to the electrode
and instrument status, pH and temperature displayed simultaneously,
and user friendly graphic symbols during calibration.
This meter is provided with a series of new diagnostic features which add
an entirely new dimension to pH measurement, by allowing the user to
dramatically improve the reliability of the measurement:
• 7 memorized buffers (pH 1.68, 4.01, 6.86, 7.01, 9.18, 10.01 and
12.45) for calibration
• Custom calibration (up to two custom buffers)
• Messages on the LCD to make the calibration easy and accurate
• Diagnostic features to alert the user when the electrode needs cleaning
• Monitoring of the electrode aging
• User‑selectable “calibration time‑out” to remind you when a new
calibration is necessary
HI9126 can also measure for Oxidation Reduction Potential in the mV
range with a resolution of 0.1 mV.
It offers an extended temperature range from:
–20 °C (–4 °F) to 120 °C (248 °F).
Remove the instrument from the packing material and examine it to
make sure that no damage has occurred during shipping. If there is any
damage, please contact your local Hanna Instruments Office.
Each meter is supplied with:
• HI1230B combination double‑junction, gel pH electrode
• HI7662 stainless steel temperature probe with 1 m (3.3’’) cable
• pH 4.01 & pH 7.01 buffer solutions, 20 mL sachet
• HI700661 electrode cleaning solution
• 100 mL plastic beaker
• 1.5V AAA Batteries (3 pcs.)
• Instruction manual
• Rugged carrying case
Note:Save all packing material until you are sure that the instrument
functions correctly. All defective items must be returned in the
original packing with the supplied accessories.
PRELIMINARY EXAMINATION
GENERAL DESCRIPTION

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1) Liquid Crystal Display (LCD).
2) RANGE key, to select pH or mV.
3) ON/OFF key, to turn the meter ON and OFF.
4) CAL key, to enter or exit calibration mode.
5) SETUP/CFM key, to enter SETUP mode or to confirm calibra‑
tion.
6) Battery compartment cap.
7) Temperature probe socket.
8) BNC electrode connector.
9) MR/CUST BUF key, to recall the stored value from memory or
to enter custom buffer values during calibration.
10) MEM/CLR key, to store the reading in memory or to clear calibra‑
tion.
11) and keys, for manual temperature setting, entering menu
parameters or changing buffer value.
12) LIGHT key, toggle to switch the display backlight on and off.
13) Secondary display.
14) Primary display.
FUNCTIONAL DESCRIPTION

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SPECIFICATIONS
Range
–2.00 to 16.00 pH
±699.9 mV / ±1999 mV
‑20.0 to 120.0 °C (–4.0 to 248.0 °F)
Resolution
0.01 pH
0.1 mV / 1 mV
0.1 °C (0.1 °F)
Accuracy
@ 20 ºC / 68 ºF
±0.01 pH
±0.2 mV / ±1 mV
±0.4 °C (±0.8 °F) (excluding probe error)
Typical EMC Deviation
±0.02 pH
±0.2 mV/ ±1 mV
±0.4 °C (±0.8 °F)
pH Calibration
1 or 2‑point, with 7 memorized buffers (pH 1.68,
4.01, 6.86, 7.01, 9.18, 10.01, 12.45) and
2 custom buffers
Offset Calibration ±1 pH
Slope Calibration From 80 to 108%
Temperature Compensation
Automatic, from –20.0 to 120.0 °C
(–4.0 to 248.0 °F) or manual
without temperature probe
pH Electrode HI1230B (included)
Temperature Probe HI7662 (included)
Input Impedance 1012 ohms
Battery Type & Life
3 x 1.5V AAA size batteries
approx. 200 hours of continuous use
without backlight (50 hours with backlight)
Auto‑off User selectable: 20 minutes or disabled
Dimensions 185 x 72 x 36 mm (7.3 x 2.8 x 1.4”)
Weight 300 g (10.6 oz.)
Environment 0 – 50 °C (32 – 122 °F)
max RH 100%
Warranty 2 years

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INITIAL PREPARATION
The meter is supplied with batteries (for details see page 19).
To prepare the instrument for use, connect the pH electrode and the
temperature probe to the BNC and temperature sockets on the top of
the instrument. The temperature probe can be used independently
to take temperature measurements, or it can be used in conjunction
with the pH electrode to utilize the meter’s Automatic Temperature
Compensation (ATC) mode. If the probe is disconnected, temperature
can also be set manually with the ARROW keys.
Turn the instrument ON by pressing ON/OFF.
At start‑up the display will show all LCD segments and then the battery
percentage while the instrument performs a self check (or as long as
the button is held).
The meter will automatically enter measurement mode.
After measurement switch the meter off. Clean the electrode and store
it with a few drops of HI70300 storage solution in the protective cap.
To save the batteries, the auto‑off feature turns the meter off after
20 minutes (no button pressed). To disable this feature, see “Setup
Menu” section on page 16.
pH MEASUREMENTS
To take a pH measurement remove the electrode
protective cap and submerse the electrode and the
temperature probe 3 cm (11/4”) into the sample
and stir gently.
If necessary, press the RANGE key until the display
shows pH mode.
Allow time for the reading to stabilize.
OPERATIONAL GUIDE

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The LCD will show the pH measurement and the temperature of the
sample.
In order to take more accurate pH measurements, make sure that the
instrument is calibrated (see page 10 for details).
The glass bulb and the junction on your electrode should always be
moist, never allow it to dry out.
If several measurements are taken successively in different samples,
rinse the electrode thoroughly with deionized or tap water and a small
amount of the sample to be measured.
The pH reading is directly affected by temperature. In order for the meter to
measure the pH accurately, temperature must be compensated for. If the
sample temperature is different from the temperature at which the pH
electrode was kept, allow a few minutes for thermal equilibration.
To use the meter’s Automatic Temperature Compensation feature, sub‑
merse the temperature probe into the sample as close to the electrode
as possible and wait for a few minutes.
If manual temperature compensation is desired the temperature
probe must be disconnected from the instrument.
The display will show the default temperature of 25 °C, or the last
temperature set the “°C” (or “°F”) indicator will blink.
The temperature can now be adjusted with the ARROW keys.

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MEM & MR FUNCTIONS
Pressing the MEM key will memorize the reading on the display and
store it in the internal memory. The pH (mV) and temperature, electrode
condition and the buffers used for calibration will be stored.
The “MEMORIZE” tag blinks and the display remains frozen until the
MEM key is pressed again.
Note: While in MEM mode, the user can switch between pH and mV
by pressing the RANGE key.
ORP MEASUREMENTS
To perform ORP measurements, connect an optional ORP electrode (see
“Accessories“ section) to the meter and turn it ON.
If necessary, enter the “mV” mode by pressing RANGE.
Submerse the ORP electrode 3 cm (11/4”) into the sample to be tested
and wait for the reading to stabilize.
Measurements within the ±699.9 mV range are displayed with 0.1 mV resolution,
while outside this range the resolution is 1 mV.
The ATC (or MTC) key is turned off because the mV readings are not
temperature compensated.
For accurate ORP measurements, the surface of the electrode must be
clean and smooth. Pretreatment solutions are available to condition the
electrode and improve the response time (see “Accessories“section).
Notes:
• When the reading is out of range, the display will flash the closest
full‑scale value.
• If using a pH electrode while in mV mode, the meter will measure
the mV generated by the pH electrode.

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A stored value can be recalled by pressing MR: the display will show
the memorized reading and the “RECALL MEMORIZED” tag, as long
as the MR key is pressed.
Note: MR will only display the range that was active when MEM
was pressed.
BACKLIGHT FEATURE
The meter is provided with a Backlight feature,
which can be easily accessed through the LIGHT
key.
Note: The backlight automatically shuts off after
approximately 1 minute of nonuse.

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pH CALIBRATION
It is recommended to calibrate the instrument frequently, if high
accuracy is required. The instrument should be recalibrated:
• Whenever the pH electrode is replaced.
• At least once a week.
• After testing aggressive chemicals.
• When extreme accuracy is required.
• When the calibration time‑out is expired (if feature is enabled).
PROCEDURE
The meter offers a choice of 7 memorized buffers (1.68, 4.01, 6.86,
7.01, 9.18, 10.01 and 12.45 pH) and two user defined values, C1 and
C2 (see “Custom Buffer Selection” section on page 12 for details).
• Pour a small quantity 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.
• Remove the protective cap and rinse the electrode with some of the
buffer solution to be used for the first calibration point.
TWO-POINT CALIBRATION
• Press the CAL key. The “CAL” and “ ” indicators will be dis‑
played. The secondary LCD will display buffer “7.01”. If a different
calibration buffer is desired (e.g. “6.86”), use the ARROW keys to
change the displayed value.
• Submerse the electrode approximately 3 cm (1¼”) into the solution,
place the temperature probe as close as possible to the electrode
and stir gently.
• The LCD will flash “WAIT NOT READY” for 12 seconds, then:
if the reading is not close to the selected buffer, “WRONG “ and
“WRONG ” will blink alternatively; if it
is close to the selected buffer the meter
will advise the user with an audible
signal (if enabled) when the reading
becomes stable and the display will
change to “READY” and blinking “CFM”.

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• Press the CFM key to confirm the calibration: the meter stores the
first calibration point; the primary LCD will show the calibrated
reading, while the secondary LCD will show the second buffer to
be used for calibration (“pH 4.01”).
If you’re going to calibrate with a different buffer, select the desired
value by pressing the arrow keys.
Note:The meter automatically skips the buffer used for the first calibra‑
tion point. A difference of at least 1.5 pH unit is required between
the two buffers: once calibrated at either pH 7.01 or 6.86, the
instrument automatically ignores the other value for the second
point (same for pH 10.01 and 9.18).
• Immerse electrode bulb approximately 3 cm (11/4”) into the second
buffer solution, place the temperature probe as close as possible to
the electrode and stir gently.
• The LCD will flash “WAIT NOT READY”
for several seconds, then:
if the reading is not close to the selected
buffer, “WRONG “ and “WRONG
” will blink alternatively;
if it is close to the selected buffer the meter
will advise the user with an audible signal
(if enabled) when the reading becomes
stable and the display will change to
“READY” and blinking “CFM”.
• Press the CFM key: the value is stored in memory and the meter
returns to measurement mode. The tags corresponding to the buffers
used for calibration and the “condition” bargraph (if enabled) will
be light up.

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ONE-POINT CALIBRATION
For optimum accuracy it is always recommended to perform a two‑point
calibration, but for a faster operation it is also possible to carry out a
single‑point calibration.
pH 7.01 or pH 6.86 (NIST) are typically used, however the meter can
be calibrated with any of the memorized calibration values.
After calibrating the first point (see two‑point calibration), press the
CAL key to end the calibration procedure.
Note:With one‑point calibration electrode “condition” is not available
and only the frame is shown. Calibration time‑out is active.
CUSTOM BUFFER SELECTION
• The meter allows the user to calibrate with custom buffers.
• To select a custom buffer press the CUST BUF key while in calibration
mode. Use the arrow keys to set the desired value for C1 (a default
of 7.00 or previously configured buffer appears).
Notes:During calibration, the secondary LCD shows the selected buffer
value; press RANGE to display the buffer temperature.
To clear a previous calibration and return to the default values,
press CLR at any time after entering the calibration mode. The
LCD will show “CLr CAL” for one second, and then will return
to normal measurement mode.
The LCD will show an empty bargraph to warn the user that the
meter is not calibrated.

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Note:To increase the speed, continuously press the ARROW keys.
• Once the desired value is reached, press
CFM to confirm the value. The meter will
continue calibration as with memorized
buffers.
• The meter will display “C2”. Use the
arrow keys to change the value of the
second custom buffer, or press CUST
BUF to select a memorized buffer.
EXPIRED CALIBRATION
The instrument has a real time clock (RTC), in order to monitor the
time elapsed since the last pH calibration.
The real time clock is reset every time the meter is calibrated and
the “expired calibration” status is triggered when the meter detects a
calibration time‑out. The CAL tag will start blinking to warn the user
that the meter should be recalibrated.
The calibration time‑out can be set (see “Setup menu” section on page
14) from 0 (function disabled) to 14 days.
For example, if a 4 days time‑out has been selected the meter will
issue the alarm exactly 4 days after the last calibration.
If the expiration value is changed (e.g. to 7 days), then the alarm
will be immediately recalculated and appear 7 days after the last
calibration.
Notes:
• When the meter is not calibrated or calibration is cleared (default
values loaded) there is no “expired calibration”, and the display
always shows a blinking CAL tag.
• When an abnormal condition in the RTC is detected the meter forces
the “expired calibration” status.

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CONDITION
The display is provided with a 5‑dot bargraph (unless disabled) which
gives an indication of the electrode status after calibration:
Bargraph indication Condition value
All 5 dots steady 81 to 100% of life
4 dots steady 61 to 80%
3 dots steady 41 to 60%
2 dots steady 21 to 40%
1 dot steady 1 to 20%
1 dot blinking 0%
Only frame is ON No info available
The “condition” bargraph remains active for 12 hours after calibration,
then only the frame is shown.
Maintenance should be provided to the sensor when two or fewer dots
are on the bargraph.
Note: When an abnormal condition in the RTC is detected, the “condition”
is cleared and only the bargraph frame is shown on the display.
CLEAN ELECTRODE
Each time pH calibration is performed, the
meter internally compares the new calibra‑
tion with the one previously stored.
When this comparison indicates a significant
difference, the “CLEAN ELECTRODE”
message blinks on the LCD to advise the
user that the pH electrode may need to
be cleaned (see “Electrode Conditioning
& Maintenance” section).
After cleaning, perform calibration.
Note: If the calibration data are cleared, the comparison is done with
the default values.

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The 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
During calibration the instrument will display the pH buffer value at
25 °C. After calibration is completed the buffer should show the value
at its temperature of measurement.
pH BUFFER TEMPERATURE
DEPENDENCE
TEMP pH BUFFERS
°C °F 1.68 4.01 6.86 7.01 9.18 10.01 12.45
0 32 1.67 4.01 6.98 7.13 9.46 10.32 13.38
5 41 1.67 4.00 6.95 7.10 9.39 10.24 13.18
10 50 1.67 4.00 6.92 7.07 9.33 10.18 12.99
15 59 1.67 4.00 6.90 7.05 9.27 10.12 12.80
20 68 1.68 4.00 6.88 7.03 9.22 10.06 12.62
25 77 1.68 4.01 6.86 7.01 9.18 10.01 12.45
30 86 1.68 4.02 6.85 7.00 9.14 9.96 12.29
35 95 1.69 4.03 6.84 6.99 9.11 9.92 12.13
40 104 1.69 4.04 6.84 6.98 9.07 9.88 11.98
45 113 1.70 4.05 6.83 6.98 9.04 9.85 11.83
50 122 1.71 4.06 6.83 6.98 9.01 9.82 11.70
55 131 1.72 4.08 6.84 6.98 8.99 9.79 11.57
60 140 1.72 4.09 6.84 6.98 8.97 9.77 11.44
65 149 1.73 4.11 6.84 6.99 8.95 9.76 11.32
70 158 1.74 4.12 6.85 6.99 8.93 9.75 11.21
75 167 1.76 4.14 6.86 7.00 8.91 9.74 11.10
80 176 1.77 4.16 6.87 7.01 8.89 9.74 11.00
85 185 1.78 4.17 6.87 7.02 8.87 9.74 10.91
90 194 1.79 4.19 6.88 7.03 8.85 9.75 10.82
95 203 1.81 4.20 6.89 7.04 8.83 9.76 10.73

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The instrument allows the user to configure several parameters through
the Setup Menu.
To enter the Setup Menu, while in measurement mode, press and hold
the SETUP key for about 5 seconds.
Once the menu is entered, each parameter can be changed by using
the arrow keys; then pressing the CFM key will confirm the value and
scroll to the next parameter.
1. Audible signal: On (default) or Off
2. Auto‑off feature: 20 minutes (default) or disabled
3. Temperature measure unit: ºC (default) or ºF
SETUP MENU

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4. Calibration segments: On (default) or Off. This enables or disables the
bargraph, the “CLEAN ELECTRODE” message and the buffer segments.
5. Calibration time‑out: 1 (default) to 14 days or disabled (0 days)
After the last parameter, press the CFM key to confirm the setting and
return to measurement mode.

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HI9126 has been precalibrated for temperature at the factory.
For optimum accuracy, it is recommended to recalibrate the meter for
temperature at least once a year. Contact your local Hanna Instruments
Office for more information.
HI9126 has been precalibrated for mV range at the factory.
For optimum accuracy, it is recommended to recalibrate the meter for
mV readings at least once a year. Contact your local Hanna Instruments
Office for more information.
mV CALIBRATION
TEMPERATURE CALIBRATION

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The instrument is supplied with batteries. First time you start working
with the instrument, insert the supplied batteries in the battery compart‑
ment observing the correct polarity (see page 20).
At start‑up the battery percentage is displayed.
If the batteries become weak, the display will flash the battery symbol
to advise the user that approximately 1 hour of working time remains.
It is recommended to change the batteries as soon as the battery
symbol appears blinking.
The meter is also provided with the BEPS (Battery Error Prevention
System) feature which automatically turns the instrument off when
the battery level is too low to ensure reliable readings. At start‑up the
display will show “0 batt” for few seconds, then the meter automati‑
cally turns off.
BATTERIES REPLACEMENT

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To replace the batteries, follow the next steps:
• Turn OFF the instrument.
• Open the battery compartment cap (located on the top of the
instrument).
• Remove old batteries.
• Insert three new 1.5V AAA batteries in the battery compartment,
observing the polarity on the rear of the instrument.
• Reattach the battery compartment cap.